38
+ − 1 ///////////////////////////////////////////////////////////////////////////////
+ − 2 /// -*- coding: UTF-8 -*-
+ − 3 ///
+ − 4 /// \file Discovery/Src/vpm.c
+ − 5 /// \brief critical_volume comment by hw
+ − 6 /// \author Heinrichs Weikamp, Erik C. Baker
+ − 7 /// \date 19-April-2014
+ − 8 ///
+ − 9 /// \details
+ − 10 ///
+ − 11 /// $Id$
+ − 12 ///////////////////////////////////////////////////////////////////////////////
+ − 13 /// \par Copyright (c) 2014-2018 Heinrichs Weikamp gmbh
+ − 14 ///
+ − 15 /// This program is free software: you can redistribute it and/or modify
+ − 16 /// it under the terms of the GNU General Public License as published by
+ − 17 /// the Free Software Foundation, either version 3 of the License, or
+ − 18 /// (at your option) any later version.
+ − 19 ///
+ − 20 /// This program is distributed in the hope that it will be useful,
+ − 21 /// but WITHOUT ANY WARRANTY; without even the implied warranty of
+ − 22 /// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ − 23 /// GNU General Public License for more details.
+ − 24 ///
+ − 25 /// You should have received a copy of the GNU General Public License
+ − 26 /// along with this program. If not, see <http://www.gnu.org/licenses/>.
+ − 27 //////////////////////////////////////////////////////////////////////////////
+ − 28 /// \par Varying Permeability Model (VPM) Decompression Program in c (converted from FORTRAN)
+ − 29 ///
+ − 30 /// Author: Erik C. Baker
+ − 31 ///
+ − 32 /// "DISTRIBUTE FREELY - CREDIT THE AUTHORS"
+ − 33 ///
+ − 34 /// This program extends the 1986 VPM algorithm (Yount & Hoffman) to include
+ − 35 /// mixed gas, repetitive, and altitude diving. Developments to the algorithm
+ − 36 /// were made by David E. Yount, Eric B. Maiken, and Erik C. Baker over a
+ − 37 /// period from 1999 to 2001. This work is dedicated in remembrance of
+ − 38 /// Professor David E. Yount who passed away on April 27, 2000.
+ − 39 ///
+ − 40 /// Notes:
+ − 41 /// 1. This program uses the sixteen (16) half-time compartments of the
+ − 42 /// Buhlmann ZH-L16 model. The optional Compartment 1b is used here with
+ − 43 /// half-times of 1.88 minutes for helium and 5.0 minutes for nitrogen.
+ − 44 ///
+ − 45 /// 2. This program uses various DEC, IBM, and Microsoft extensions which
+ − 46 /// may not be supported by all FORTRAN compilers. Comments are made with
+ − 47 /// a capital "C" in the first column or an exclamation point "!" placed
+ − 48 /// in a line after code. An asterisk "*" in column 6 is a continuation
+ − 49 /// of the previous line. All code, except for line numbers, starts in
+ − 50 /// column 7.
+ − 51 ///
+ − 52 /// 3. Comments and suggestions for improvements are welcome. Please
+ − 53 /// respond by e-mail to: EBaker@se.aeieng.com
+ − 54 ///
+ − 55 /// Acknowledgment: Thanks to Kurt Spaugh for recommendations on how to clean
+ − 56 /// up the code.
+ − 57 /// ===============================================================================
+ − 58 /// Converted to vpmdeco.c using f2c; R.McGinnis (CABER Swe) 5/01
+ − 59 /// ===============================================================================
+ − 60 ///
+ − 61 /// ************************ Heirichs Weipkamp **************************************
+ − 62 ///
+ − 63 /// The original Yount & Baker code has been adjusted for real life calculation.
+ − 64 ///
+ − 65 /// 1) The original main function has been split in several functions
+ − 66 ///
+ − 67 /// 2) When the deco zone is reached (while ascending) the gradient factors are kept fix
+ − 68 /// and critical volume algorithm is switched of. maxfirststopdepth is kept fix
+ − 69 /// to make shure Boeyls Law algorithm works correctly
+ − 70 ///
+ − 71 /// 4) gas_loadings_ascent_descend heeds all gaschanges and CCR support has been added
+ − 72 ///
+ − 73
+ − 74 #include <stdio.h>
+ − 75 #include <stdlib.h>
+ − 76 #include <string.h>
+ − 77 #include <math.h>
+ − 78 #include <time.h>
+ − 79
+ − 80 #include "vpm.h"
+ − 81 #include "decom.h"
+ − 82
+ − 83 #define GAS_N2 0
+ − 84 #define GAS_HE 1
+ − 85
290
+ − 86 static const _Bool buehlmannSafety = true;
38
+ − 87 /* Common Block Declarations */
+ − 88
+ − 89 extern const float SURFACE_TENSION_GAMMA; //!Adj. Range: 0.015 to 0.065 N/m
+ − 90 extern const float SKIN_COMPRESSION_GAMMAC; //!Adj. Range: 0.160 to 0.290 N/m
+ − 91 extern const float UNITS_FACTOR;
+ − 92 extern const float WATER_VAPOR_PRESSURE; // (Schreiner value) based on respiratory quotien
+ − 93 extern const float CRIT_VOLUME_PARAMETER_LAMBDA; //!Adj. Range: 6500 to 8300 fsw-min
290
+ − 94 //extern const float GRADIENT_ONSET_OF_IMPERM_ATM; //!Adj. Range: 5.0 to 10.0 atm
38
+ − 95 extern const float REGENERATION_TIME_CONSTANT; //!Adj. Range: 10080 to 51840 min
290
+ − 96 //extern const float PRESSURE_OTHER_GASES_MMHG; //!Constant value for PO2 up to 2 atm
38
+ − 97 extern const float CONSTANT_PRESSURE_OTHER_GASES; // PRESSURE_OTHER_GASES_MMHG / 760. * UNITS_FACTOR;
+ − 98
+ − 99 extern const float HELIUM_TIME_CONSTANT[];
+ − 100 extern const float NITROGEN_TIME_CONSTANT[];
+ − 101
290
+ − 102 static float minimum_deco_stop_time;
+ − 103 static float run_time, run_time_first_stop;
+ − 104 static float segment_time;
+ − 105 static short mix_number;
+ − 106 static float barometric_pressure;
+ − 107 static _Bool altitude_dive_algorithm_off;
+ − 108 static _Bool units_equal_fsw, units_equal_msw;
38
+ − 109
+ − 110 /* by hw 11.06.2015 to allow */
290
+ − 111 static float gCNS_VPM;
38
+ − 112
290
+ − 113 static float helium_pressure[16], nitrogen_pressure[16];
+ − 114 static float surface_phase_volume_time[16];
+ − 115 static float regenerated_radius_he[16], regenerated_radius_n2[16];
+ − 116 static float allowable_gradient_he[16], allowable_gradient_n2[16];
38
+ − 117
+ − 118 //_Bool deco_zone_reached;
290
+ − 119 static _Bool critical_volume_algorithm_off;
+ − 120 static float max_first_stop_depth;
+ − 121 static float max_deco_ceiling_depth;
38
+ − 122 //Boylslaw compensation
290
+ − 123 static float deco_gradient_he[16];
+ − 124 static float deco_gradient_n2[16];
+ − 125 static int vpm_calc_what;
+ − 126 static int count_critical_volume_iteration;
+ − 127 static short number_of_changes;
+ − 128 static float depth_change[11];
+ − 129 static float step_size_change[11];
+ − 130 static float rate_change[11];
+ − 131 static short mix_change[11];
38
+ − 132
290
+ − 133 static const _Bool vpm_b = true;
38
+ − 134
+ − 135 extern const float float_buehlmann_N2_factor_expositon_20_seconds[];
+ − 136 extern const float float_buehlmann_He_factor_expositon_20_seconds[];
+ − 137 extern const float float_buehlmann_N2_factor_expositon_one_minute[];
+ − 138 extern const float float_buehlmann_He_factor_expositon_one_minute[];
+ − 139 extern const float float_buehlmann_N2_factor_expositon_five_minutes[];
+ − 140 extern const float float_buehlmann_He_factor_expositon_five_minutes[];
+ − 141 extern const float float_buehlmann_N2_factor_expositon_one_hour[];
+ − 142 extern const float float_buehlmann_He_factor_expositon_one_hour[];
+ − 143
290
+ − 144 static float depth_start_of_deco_calc;
+ − 145 static float depth_start_of_deco_zone;
+ − 146 static float first_stop_depth;
+ − 147 static float run_time_start_of_deco_zone;
38
+ − 148
290
+ − 149 static float r_nint(float *x);
+ − 150 static float r_int(float *x);
+ − 151 static _Bool nullzeit_unter60;
+ − 152 static int vpm_calc_status;
+ − 153 static _Bool buehlmann_wait_exceeded = false;
38
+ − 154
290
+ − 155 static SLifeData* pInput = NULL;
+ − 156 static SVpm* pVpm = NULL;
+ − 157 static SDecoinfo* pDecoInfo = NULL;
+ − 158 static SDiveSettings* pDiveSettings = NULL;
+ − 159
+ − 160 static float r_nint(float *x)
38
+ − 161 {
+ − 162 return( (*x)>=0 ?
+ − 163 floorf(*x + 0.5f) : -floorf(0.5f - *x) );
+ − 164 }
+ − 165
290
+ − 166 static float r_int(float *x)
38
+ − 167 {
+ − 168 return( (*x>0) ? floorf(*x) : -floorf(- *x) );
+ − 169 }
+ − 170
+ − 171 /** private functions
+ − 172 */
290
+ − 173 extern int radius_root_finder (float *a, float *b, float *c,float *low_bound, float *high_bound, float *ending_radius);
38
+ − 174
290
+ − 175 static int nuclear_regeneration(float *dive_time);// clock_();
+ − 176 static int calc_deco_ceiling(float *deco_ceiling_depth,_Bool fallowablw);
+ − 177 static int critical_volume(float *deco_phase_volume_time); ;
+ − 178 static int calc_start_of_deco_zone(float *starting_depth, float *rate, float *depth_start_of_deco_zone);
+ − 179 static int calc_initial_allowable_gradient(void);
+ − 180 static void decompression_stop(float *deco_stop_depth, float *step_size, _Bool final_deco_calculation);
+ − 181 static int gas_loadings_ascent_descen(float* helium_pressure, float* nitrogen_pressure, float starting_depth,float ending_depth, float rate,_Bool check_gas_change);
+ − 182 static int calc_surface_phase_volume_time(void);
+ − 183 static int calc_max_actual_gradient(float *deco_stop_depth);
+ − 184 static int projected_ascent(float *starting_depth, float *rate, float *deco_stop_depth, float *step_size);
+ − 185 static void vpm_calc_deco(void);
+ − 186 static int vpm_calc_critcal_volume(_Bool begin,_Bool calc_nulltime);
+ − 187 static int vpm_check_converged(_Bool calc_nulltime);
+ − 188 static int vpm_calc_final_deco(_Bool begin);
+ − 189 static void BOYLES_LAW_COMPENSATION (float* First_Stop_Depth,float * Deco_Stop_Depth,float* Step_Size);
292
+ − 190 static int vpm_calc_ndl(void);
290
+ − 191 static void vpm_init_1(void);
+ − 192 static void vpm_calc_deco_ceiling(void);
38
+ − 193
290
+ − 194 static void vpm_init_1(void)
38
+ − 195 {
+ − 196 units_equal_msw = true;
+ − 197 units_equal_fsw = false;
+ − 198 altitude_dive_algorithm_off= true; //!Options: ON or OFF
+ − 199 minimum_deco_stop_time=1.0; //!Options: float positive number
+ − 200 critical_volume_algorithm_off= false; //!Options: ON or OFF
+ − 201 run_time = 0.;
+ − 202 //barometric_pressure = dive_data.surface * 10;
+ − 203
+ − 204 //mix_number = dive_data.selected_gas + 1;
+ − 205
+ − 206 max_first_stop_depth = 0;
+ − 207 max_deco_ceiling_depth = 0;
+ − 208 //deco_zone_reached = false;
+ − 209 depth_start_of_deco_calc = 0;
+ − 210 depth_start_of_deco_zone = 0;
+ − 211 first_stop_depth = 0;
+ − 212 run_time_start_of_deco_zone = 0;
+ − 213
+ − 214 gCNS_VPM = 0;
+ − 215 }
+ − 216
+ − 217 float vpm_get_CNS(void)
+ − 218 {
+ − 219 return gCNS_VPM;
+ − 220 }
+ − 221
+ − 222 int vpm_calc(SLifeData* pINPUT,
+ − 223 SDiveSettings* pSettings,
+ − 224 SVpm* pVPM,
+ − 225 SDecoinfo*
+ − 226 pDECOINFO,
+ − 227 int calc_what)
+ − 228 {
+ − 229 vpm_init_1();
+ − 230 //decom_CreateGasChangeList(pSettings, pINPUT);
+ − 231 vpm_calc_what = calc_what;
+ − 232 /**clear decoInfo*/
+ − 233 pDECOINFO->output_time_to_surface_seconds = 0;
+ − 234 pDECOINFO->output_ndl_seconds = 0;
+ − 235 pDECOINFO->output_ceiling_meter = 0;
247
+ − 236 pDECOINFO->super_saturation = 0;
38
+ − 237 uint8_t tmp_calc_status;
+ − 238 for(int i=0;i<DECOINFO_STRUCT_MAX_STOPS;i++)
+ − 239 {
+ − 240 pDECOINFO->output_stop_length_seconds[i] = 0;
+ − 241 }
+ − 242
305
305f251cc981
bugfix, consistency: show deco/NDL really after 1 minute divetime
Jan Mulder <jlmulder@xs4all.nl>
diff
changeset
+ − 243 if(pINPUT->dive_time_seconds_without_surface_time < 60)
38
+ − 244 {
292
+ − 245 vpm_calc_status = CALC_NDL;
38
+ − 246 return vpm_calc_status;
+ − 247 }
+ − 248 pVpm = pVPM;
+ − 249 pInput = pINPUT;
+ − 250 pDecoInfo = pDECOINFO;
+ − 251 pDiveSettings = pSettings;
+ − 252
292
+ − 253 if(vpm_calc_status == CALC_NDL)
38
+ − 254 {
292
+ − 255 tmp_calc_status = vpm_calc_ndl();
38
+ − 256 }
+ − 257 else
+ − 258 {
+ − 259 tmp_calc_status = CALC_BEGIN;
+ − 260 }
+ − 261 //Normal Deco calculation
292
+ − 262 if(tmp_calc_status != CALC_NDL)
38
+ − 263 {
+ − 264 max_first_stop_depth = pVpm->max_first_stop_depth_save;
+ − 265 run_time_start_of_deco_zone = pVpm->run_time_start_of_deco_zone_save;
+ − 266 depth_start_of_deco_zone = pVpm->depth_start_of_deco_zone_save;
+ − 267 for (int i = 0; i < 16; ++i) {
+ − 268 helium_pressure[i] = pInput->tissue_helium_bar[i] * 10;
+ − 269 nitrogen_pressure[i] = pInput->tissue_nitrogen_bar[i] * 10;
+ − 270 }
+ − 271 vpm_calc_deco();
+ − 272 tmp_calc_status = vpm_calc_critcal_volume(true,false);
+ − 273 if(vpm_calc_what == DECOSTOPS)
+ − 274 {
+ − 275 pVpm->max_first_stop_depth_save = max_first_stop_depth;
+ − 276 pVpm->run_time_start_of_deco_zone_save = run_time_start_of_deco_zone;
+ − 277 pVpm->depth_start_of_deco_zone_save = depth_start_of_deco_zone;
+ − 278 }
+ − 279 }
+ − 280
+ − 281 //Only Decostops not futute stops
+ − 282 if(vpm_calc_what == DECOSTOPS)
+ − 283 vpm_calc_status = tmp_calc_status;
+ − 284 return vpm_calc_status;
+ − 285 }
+ − 286
+ − 287 void vpm_saturation_after_ascent(SLifeData* input)
+ − 288 {
+ − 289 int i = 0;
+ − 290 for (i = 0; i < 16; ++i) {
+ − 291 pInput->tissue_helium_bar[i] = helium_pressure[i] / 10;
+ − 292 pInput->tissue_nitrogen_bar[i] = nitrogen_pressure[i] / 10;
+ − 293 }
+ − 294 pInput->pressure_ambient_bar = pInput->pressure_surface_bar;
+ − 295 }
+ − 296 /* =============================================================================== */
+ − 297 /* NOTE ABOUT PRESSURE UNITS USED IN CALCULATIONS: */
+ − 298 /* It is the convention in decompression calculations to compute all gas */
+ − 299 /* loadings, absolute pressures, partial pressures, etc., in the units of */
+ − 300 /* depth pressure that you are diving - either feet of seawater (fsw) or */
+ − 301 /* meters of seawater (msw). This program follows that convention with the */
+ − 302 /* the exception that all VPM calculations are performed in SI units (by */
+ − 303 /* necessity). Accordingly, there are several conversions back and forth */
+ − 304 /* between the diving pressure units and the SI units. */
+ − 305 /* =============================================================================== */
+ − 306 /* =============================================================================== */
+ − 307 /* FUNCTION SUBPROGRAM FOR GAS LOADING CALCULATIONS - ASCENT AND DESCENT */
+ − 308 /* =============================================================================== */
+ − 309
+ − 310
+ − 311
+ − 312 /* =============================================================================== */
+ − 313 /* SUBROUTINE GAS_LOADINGS_ASCENT_DESCENT */
+ − 314 /* Purpose: This subprogram applies the Schreiner equation to update the */
+ − 315 /* gas loadings (partial pressures of helium and nitrogen) in the half-time */
+ − 316 /* compartments due to a linear ascent or descent segment at a constant rate. */
+ − 317 /* =============================================================================== */
+ − 318
290
+ − 319 static int gas_loadings_ascent_descen(float* helium_pressure,
38
+ − 320 float* nitrogen_pressure,
+ − 321 float starting_depth,
+ − 322 float ending_depth,
+ − 323 float rate,_Bool check_gas_change)
+ − 324 {
+ − 325 short i;
+ − 326 float initial_inspired_n2_pressure,
+ − 327 initial_inspired_he_pressure, nitrogen_rate,
+ − 328 last_run_time,
+ − 329 starting_ambient_pressure,
+ − 330 ending_ambient_pressure;
+ − 331 float initial_helium_pressure[16];
+ − 332 float initial_nitrogen_pressure[16];
+ − 333 float helium_rate;
+ − 334 float fraction_helium_begin;
+ − 335 float fraction_helium_end;
+ − 336 float fraction_nitrogen_begin;
+ − 337 float fraction_nitrogen_end;
+ − 338 float ending_depth_tmp = ending_depth;
+ − 339 float segment_time_tmp = 0;
+ − 340 /* loop */
+ − 341 /* =============================================================================== */
+ − 342 /* CALCULATIONS */
+ − 343 /* =============================================================================== */
+ − 344 segment_time = (ending_depth_tmp - starting_depth) / rate;
+ − 345 last_run_time = run_time;
+ − 346 run_time = last_run_time + segment_time;
+ − 347 do {
+ − 348 ending_depth_tmp = ending_depth;
+ − 349 if (starting_depth > ending_depth && check_gas_change && number_of_changes > 1)
+ − 350 {
+ − 351 for (i = 1; i < number_of_changes; ++i)
+ − 352 {
+ − 353 if (depth_change[i] < starting_depth && depth_change[i] > ending_depth)
+ − 354 {
+ − 355 ending_depth_tmp = depth_change[i];
+ − 356 break;
+ − 357 }
+ − 358 }
+ − 359 for (i = 1; i < number_of_changes; ++i)
+ − 360 {
+ − 361 if (depth_change[i] >= starting_depth)
+ − 362 {
+ − 363 mix_number = mix_change[i];
+ − 364 }
+ − 365 }
+ − 366 }
+ − 367 segment_time_tmp = (ending_depth_tmp - starting_depth) / rate;
+ − 368 ending_ambient_pressure = ending_depth_tmp + barometric_pressure;
+ − 369 starting_ambient_pressure = starting_depth + barometric_pressure;
+ − 370 decom_get_inert_gases( starting_ambient_pressure / 10, (&pDiveSettings->decogaslist[mix_number]), &fraction_nitrogen_begin, &fraction_helium_begin );
+ − 371 decom_get_inert_gases( ending_ambient_pressure / 10, (&pDiveSettings->decogaslist[mix_number]), &fraction_nitrogen_end, &fraction_helium_end );
+ − 372
+ − 373 initial_inspired_he_pressure = (starting_ambient_pressure - WATER_VAPOR_PRESSURE) * fraction_helium_begin;
+ − 374 initial_inspired_n2_pressure = (starting_ambient_pressure - WATER_VAPOR_PRESSURE) * fraction_nitrogen_begin;
+ − 375 //helium_rate = *rate * fraction_helium[mix_number - 1];
+ − 376 helium_rate = ((ending_ambient_pressure - WATER_VAPOR_PRESSURE)* fraction_helium_end - initial_inspired_he_pressure)/segment_time_tmp;
+ − 377 //nitrogen_rate2 = *rate * fraction_nitrogen[mix_number - 1];
+ − 378 nitrogen_rate = ((ending_ambient_pressure - WATER_VAPOR_PRESSURE)* fraction_nitrogen_end - initial_inspired_n2_pressure)/segment_time_tmp;
+ − 379
+ − 380
+ − 381 decom_oxygen_calculate_cns_stage_SchreinerStyle(segment_time_tmp,&pDiveSettings->decogaslist[mix_number],starting_ambient_pressure/10,ending_ambient_pressure/10,&gCNS_VPM);
+ − 382 //if(fabs(nitrogen_rate - nitrogen_rate2) > 0.000001)
+ − 383 //return -2;
+ − 384 for (i = 1; i <= 16; ++i)
+ − 385 {
+ − 386 initial_helium_pressure[i - 1] = helium_pressure[i - 1];
+ − 387 initial_nitrogen_pressure[i - 1] = nitrogen_pressure[i - 1];
+ − 388 helium_pressure[i - 1] =
+ − 389 schreiner_equation__2(&initial_inspired_he_pressure,
+ − 390 &helium_rate,
+ − 391 &segment_time,
+ − 392 &HELIUM_TIME_CONSTANT[i - 1],
+ − 393 &initial_helium_pressure[i - 1]);
+ − 394 nitrogen_pressure[i - 1] =
+ − 395 schreiner_equation__2(&initial_inspired_n2_pressure,
+ − 396 &nitrogen_rate,
+ − 397 &segment_time,
+ − 398 &NITROGEN_TIME_CONSTANT[i - 1],
+ − 399 &initial_nitrogen_pressure[i - 1]);
+ − 400
+ − 401 //nextround???
+ − 402
+ − 403 }
+ − 404 starting_depth = ending_depth_tmp;
+ − 405 } while(ending_depth_tmp > ending_depth);
+ − 406
+ − 407 return 0;
+ − 408 } /* gas_loadings_ascent_descen */
+ − 409
290
+ − 410 static float last_phase_volume_time[16];
+ − 411 static float n2_pressure_start_of_deco_zone[16];
+ − 412 static float he_pressure_start_of_deco_zone[16];
+ − 413 static float phase_volume_time[16];
+ − 414 static float n2_pressure_start_of_ascent[16];
+ − 415 static float he_pressure_start_of_ascent[16];
+ − 416 static float run_time_start_of_deco_calc;
+ − 417 static float starting_depth;
+ − 418 static float last_run_time;
+ − 419 static float deco_phase_volume_time;
+ − 420 static float run_time_start_of_ascent;
+ − 421 static float rate;
+ − 422 static float step_size;
+ − 423 static _Bool vpm_violates_buehlmann;
38
+ − 424
290
+ − 425 static void vpm_calc_deco(void)
38
+ − 426 {
+ − 427 /* System generated locals */
+ − 428
+ − 429 //float deepest_possible_stop_depth;
+ − 430 // altitude_of_dive,
+ − 431 short i;
+ − 432 int j = 0;
+ − 433
+ − 434 // float rounding_operation;
+ − 435
+ − 436 /* =============================================================================== */
+ − 437 /* INPUT PARAMETERS TO BE USED FOR STAGED DECOMPRESSION AND SAVE IN ARRAYS. */
+ − 438 /* ASSIGN INITAL PARAMETERS TO BE USED AT START OF ASCENT */
+ − 439 /* The user has the ability to change mix, ascent rate, and step size in any */
+ − 440 /* combination at any depth during the ascent. */
+ − 441 /* =============================================================================== */
+ − 442
+ − 443 run_time = ((float)pInput->dive_time_seconds )/ 60;
+ − 444 count_critical_volume_iteration = 0;
+ − 445 number_of_changes = 1;
+ − 446
+ − 447 barometric_pressure = pInput->pressure_surface_bar * 10;
+ − 448 depth_change[0] =(pInput->pressure_ambient_bar - pInput->pressure_surface_bar)* 10;
+ − 449 mix_change[0] = 0;
+ − 450 rate_change[0 ] = -10;// neu 160215 hw, zuvor: -12;
+ − 451 step_size_change[0] = 3;
+ − 452 vpm_violates_buehlmann = false;
+ − 453
+ − 454 for (i = 1; i < BUEHLMANN_STRUCT_MAX_GASES; i++)
+ − 455 {
+ − 456 depth_change[i] = 0;
+ − 457 mix_change[i] = 0;
+ − 458 }
+ − 459 j = 0;
+ − 460
+ − 461 for (i = 1; i < BUEHLMANN_STRUCT_MAX_GASES; i++)
+ − 462 {
+ − 463 if(pDiveSettings->decogaslist[i].change_during_ascent_depth_meter_otherwise_zero >= depth_change[0] + 1)
+ − 464 continue;
+ − 465
+ − 466 if(pDiveSettings->decogaslist[i].change_during_ascent_depth_meter_otherwise_zero <= 0)
+ − 467 break;
+ − 468
+ − 469 j++;
+ − 470 number_of_changes ++;
+ − 471 depth_change[j] = pDiveSettings->decogaslist[i].change_during_ascent_depth_meter_otherwise_zero ;
+ − 472 mix_change[j] = i;
+ − 473 rate_change[j] = -10;// neu 160215 hw, zuvor: -12;
+ − 474 step_size_change[j] = 3;
+ − 475 }
+ − 476
+ − 477 starting_depth = depth_change[0] ;
+ − 478 mix_number = mix_change[0] ;
+ − 479 rate = rate_change[0];
+ − 480 step_size = step_size_change[0];
+ − 481
+ − 482 for (i = 0; i < 16; ++i) {
+ − 483 he_pressure_start_of_ascent[i ] = helium_pressure[i];
+ − 484 n2_pressure_start_of_ascent[i] = nitrogen_pressure[i];
+ − 485 }
+ − 486 run_time_start_of_ascent = run_time;
+ − 487 if(starting_depth <= depth_start_of_deco_zone && vpm_calc_what == DECOSTOPS)
+ − 488 {
+ − 489 pVpm->deco_zone_reached = true;
+ − 490 depth_start_of_deco_calc = starting_depth;
+ − 491 critical_volume_algorithm_off = true;
+ − 492 }
+ − 493 else
+ − 494 {
+ − 495 //if(deco_zone_reached)
+ − 496 //{
+ − 497 pVpm->deco_zone_reached = false;
+ − 498 critical_volume_algorithm_off = false;
+ − 499 //max_first_stop_depth = 0;
+ − 500 //max_first_stop_depth_save = 0;
+ − 501 //}
+ − 502 /* =============================================================================== */
+ − 503 /* BEGIN PROCESS OF ASCENT AND DECOMPRESSION */
+ − 504 /* First, calculate the regeneration of critical radii that takes place over */
+ − 505 /* the dive time. The regeneration time constant has a time scale of weeks */
+ − 506 /* so this will have very little impact on dives of normal length, but will */
+ − 507 /* have major impact for saturation dives. */
+ − 508 /* =============================================================================== */
+ − 509
+ − 510 nuclear_regeneration(&run_time);
+ − 511
+ − 512 /* =============================================================================== */
+ − 513 /* CALCULATE INITIAL ALLOWABLE GRADIENTS FOR ASCENT */
+ − 514 /* This is based on the maximum effective crushing pressure on critical radii */
+ − 515 /* in each compartment achieved during the dive profile. */
+ − 516 /* =============================================================================== */
+ − 517
+ − 518 calc_initial_allowable_gradient();
+ − 519
+ − 520 /* =============================================================================== */
+ − 521 /* SAVE VARIABLES AT START OF ASCENT (END OF BOTTOM TIME) SINCE THESE WILL */
+ − 522 /* BE USED LATER TO COMPUTE THE FINAL ASCENT PROFILE THAT IS WRITTEN TO THE */
+ − 523 /* OUTPUT FILE. */
+ − 524 /* The VPM uses an iterative process to compute decompression schedules so */
+ − 525 /* there will be more than one pass through the decompression loop. */
+ − 526 /* =============================================================================== */
+ − 527
+ − 528 /* =============================================================================== */
+ − 529 /* CALCULATE THE DEPTH WHERE THE DECOMPRESSION ZONE BEGINS FOR THIS PROFILE */
+ − 530 /* BASED ON THE INITIAL ASCENT PARAMETERS AND WRITE THE DEEPEST POSSIBLE */
+ − 531 /* DECOMPRESSION STOP DEPTH TO THE OUTPUT FILE */
+ − 532 /* Knowing where the decompression zone starts is very important. Below */
+ − 533 /* that depth there is no possibility for bubble formation because there */
+ − 534 /* will be no supersaturation gradients. Deco stops should never start */
+ − 535 /* below the deco zone. The deepest possible stop deco stop depth is */
+ − 536 /* defined as the next "standard" stop depth above the point where the */
+ − 537 /* leading compartment enters the deco zone. Thus, the program will not */
+ − 538 /* base this calculation on step sizes larger than 10 fsw or 3 msw. The */
+ − 539 /* deepest possible stop depth is not used in the program, per se, rather */
+ − 540 /* it is information to tell the diver where to start putting on the brakes */
+ − 541 /* during ascent. This should be prominently displayed by any deco program. */
+ − 542 /* =============================================================================== */
+ − 543
+ − 544 calc_start_of_deco_zone(&starting_depth, &rate, &depth_start_of_deco_zone);
+ − 545 /* =============================================================================== */
+ − 546 /* TEMPORARILY ASCEND PROFILE TO THE START OF THE DECOMPRESSION ZONE, SAVE */
+ − 547 /* VARIABLES AT THIS POINT, AND INITIALIZE VARIABLES FOR CRITICAL VOLUME LOOP */
+ − 548 /* The iterative process of the VPM Critical Volume Algorithm will operate */
+ − 549 /* only in the decompression zone since it deals with excess gas volume */
+ − 550 /* released as a result of supersaturation gradients (not possible below the */
+ − 551 /* decompression zone). */
+ − 552 /* =============================================================================== */
+ − 553 gas_loadings_ascent_descen(helium_pressure,nitrogen_pressure, starting_depth, depth_start_of_deco_zone, rate, true);
+ − 554
+ − 555 run_time_start_of_deco_zone = run_time;
+ − 556 depth_start_of_deco_calc = depth_start_of_deco_zone;
+ − 557
+ − 558 for (i = 0; i < 16; ++i)
+ − 559 {
+ − 560 pVpm->max_actual_gradient[i] = 0.;
+ − 561 }
+ − 562 }
+ − 563
+ − 564 for (i = 0; i < 16; ++i)
+ − 565 {
+ − 566 surface_phase_volume_time[i] = 0.;
+ − 567 last_phase_volume_time[i] = 0.;
+ − 568 he_pressure_start_of_deco_zone[i] = helium_pressure[i];
+ − 569 n2_pressure_start_of_deco_zone[i] = nitrogen_pressure[i];
+ − 570 //pVpm->max_actual_gradient[i] = 0.;
+ − 571 }
+ − 572 run_time_start_of_deco_calc = run_time;
+ − 573 }
+ − 574 /* =============================================================================== */
+ − 575 /* START OF CRITICAL VOLUME LOOP */
+ − 576 /* This loop operates between Lines 50 and 100. If the Critical Volume */
+ − 577 /* Algorithm is toggled "off" in the program settings, there will only be */
+ − 578 /* one pass through this loop. Otherwise, there will be two or more passes */
+ − 579 /* through this loop until the deco schedule is "converged" - that is when a */
+ − 580 /* comparison between the phase volume time of the present iteration and the */
+ − 581 /* last iteration is less than or equal to one minute. This implies that */
+ − 582 /* the volume of released gas in the most recent iteration differs from the */
+ − 583 /* "critical" volume limit by an acceptably small amount. The critical */
+ − 584 /* volume limit is set by the Critical Volume Parameter Lambda in the program */
+ − 585 /* settings (default setting is 7500 fsw-min with adjustability range from */
+ − 586 /* from 6500 to 8300 fsw-min according to Bruce Wienke). */
+ − 587 /* =============================================================================== */
+ − 588 /* L50: */
+ − 589
290
+ − 590 static float deco_stop_depth;
+ − 591 static int vpm_calc_critcal_volume(_Bool begin,
38
+ − 592 _Bool calc_nulltime)
+ − 593 { /* loop will run continuous there is an exit stateme */
+ − 594
+ − 595 short i;
+ − 596
+ − 597 float rounding_operation2;
+ − 598 //float ending_depth;
+ − 599 float deco_ceiling_depth;
+ − 600
+ − 601 //float deco_time;
+ − 602 int count = 0;
+ − 603 _Bool first_stop;
+ − 604 int dp = 0;
+ − 605 float tissue_He_saturation[16];
+ − 606 float tissue_N2_saturation[16];
+ − 607 float vpm_buehlmann_safety_gradient = 1.0f - (((float)pDiveSettings->vpm_conservatism) / 40);
+ − 608 /* =============================================================================== */
+ − 609 /* CALCULATE CURRENT DECO CEILING BASED ON ALLOWABLE SUPERSATURATION */
+ − 610 /* GRADIENTS AND SET FIRST DECO STOP. CHECK TO MAKE SURE THAT SELECTED STEP */
+ − 611 /* SIZE WILL NOT ROUND UP FIRST STOP TO A DEPTH THAT IS BELOW THE DECO ZONE. */
+ − 612 /* =============================================================================== */
+ − 613 if(begin)
+ − 614 {
+ − 615 if(depth_start_of_deco_calc < max_first_stop_depth )
+ − 616 {
+ − 617 if(vpm_b)
+ − 618 {
+ − 619 BOYLES_LAW_COMPENSATION(&max_first_stop_depth, &depth_start_of_deco_calc, &step_size);
+ − 620 }
+ − 621 calc_deco_ceiling(&deco_ceiling_depth, false);
+ − 622 }
+ − 623 else
+ − 624 calc_deco_ceiling(&deco_ceiling_depth, true);
+ − 625
+ − 626
+ − 627 if (deco_ceiling_depth <= 0.0f) {
+ − 628 deco_stop_depth = 0.0f;
+ − 629 } else {
+ − 630 rounding_operation2 = deco_ceiling_depth / step_size + ( float)0.5f;
+ − 631 deco_stop_depth = r_nint(&rounding_operation2) * step_size;
+ − 632 }
+ − 633
+ − 634 // buehlmann safety
+ − 635 if(buehlmannSafety)
+ − 636 {
+ − 637 for (i = 0; i < 16; i++)
+ − 638 {
+ − 639 tissue_He_saturation[i] = helium_pressure[i] / 10;
+ − 640 tissue_N2_saturation[i] = nitrogen_pressure[i] / 10;
+ − 641 }
+ − 642
+ − 643 if(!decom_tissue_test_tolerance(tissue_N2_saturation, tissue_He_saturation, vpm_buehlmann_safety_gradient, (deco_stop_depth / 10.0f) + pInput->pressure_surface_bar))
+ − 644 {
+ − 645
+ − 646 vpm_violates_buehlmann = true;
+ − 647 do {
+ − 648 deco_stop_depth += 3;
+ − 649 } while (!decom_tissue_test_tolerance(tissue_N2_saturation, tissue_He_saturation, vpm_buehlmann_safety_gradient, (deco_stop_depth / 10.0f) + pInput->pressure_surface_bar));
+ − 650 }
+ − 651 }
+ − 652
+ − 653 /* =============================================================================== */
+ − 654 /* PERFORM A SEPARATE "PROJECTED ASCENT" OUTSIDE OF THE MAIN PROGRAM TO MAKE */
+ − 655 /* SURE THAT AN INCREASE IN GAS LOADINGS DURING ASCENT TO THE FIRST STOP WILL */
+ − 656 /* NOT CAUSE A VIOLATION OF THE DECO CEILING. IF SO, ADJUST THE FIRST STOP */
+ − 657 /* DEEPER BASED ON STEP SIZE UNTIL A SAFE ASCENT CAN BE MADE. */
+ − 658 /* Note: this situation is a possibility when ascending from extremely deep */
+ − 659 /* dives or due to an unusual gas mix selection. */
+ − 660 /* CHECK AGAIN TO MAKE SURE THAT ADJUSTED FIRST STOP WILL NOT BE BELOW THE */
+ − 661 /* DECO ZONE. */
+ − 662 /* =============================================================================== */
+ − 663 if (deco_stop_depth < depth_start_of_deco_calc)
+ − 664 {
+ − 665 projected_ascent(&depth_start_of_deco_calc, &rate, &deco_stop_depth, &step_size);
+ − 666 }
+ − 667
+ − 668 /*if (deco_stop_depth > depth_start_of_deco_zone) {
+ − 669 printf("\t\n");
+ − 670 printf(fmt_905);
+ − 671 printf(fmt_900);
+ − 672 printf("\nPROGRAM TERMINATED\n");
+ − 673 exit(1);
+ − 674 }*/
+ − 675
+ − 676 /* =============================================================================== */
+ − 677 /* HANDLE THE SPECIAL CASE WHEN NO DECO STOPS ARE REQUIRED - ASCENT CAN BE */
+ − 678 /* MADE DIRECTLY TO THE SURFACE */
+ − 679 /* Write ascent data to output file and exit the Critical Volume Loop. */
+ − 680 /* =============================================================================== */
+ − 681
+ − 682 if (deco_stop_depth == 0.0f)
+ − 683 {
+ − 684 if(calc_nulltime)
+ − 685 {
+ − 686 return CALC_END;
+ − 687 }
+ − 688 if(pVpm->deco_zone_reached)
+ − 689 {
+ − 690 for(dp = 0;dp < DECOINFO_STRUCT_MAX_STOPS;dp++)
+ − 691 {
+ − 692 pDecoInfo->output_stop_length_seconds[dp] = 0;
+ − 693 }
+ − 694 pDecoInfo->output_ndl_seconds = 0;
+ − 695 }
+ − 696
292
+ − 697 return CALC_NDL;
38
+ − 698 /* exit the critical volume l */
+ − 699 }
+ − 700
+ − 701 /* =============================================================================== */
+ − 702 /* ASSIGN VARIABLES FOR ASCENT FROM START OF DECO ZONE TO FIRST STOP. SAVE */
+ − 703 /* FIRST STOP DEPTH FOR LATER USE WHEN COMPUTING THE FINAL ASCENT PROFILE */
+ − 704 /* =============================================================================== */
+ − 705 deco_stop_depth = fmaxf(deco_stop_depth,(float)pDiveSettings->last_stop_depth_bar * 10);
+ − 706 starting_depth = depth_start_of_deco_calc;
+ − 707 first_stop_depth = deco_stop_depth;
+ − 708 first_stop = true;
+ − 709 }
+ − 710 /* =============================================================================== */
+ − 711 /* DECO STOP LOOP BLOCK WITHIN CRITICAL VOLUME LOOP */
+ − 712 /* This loop computes a decompression schedule to the surface during each */
+ − 713 /* iteration of the critical volume loop. No output is written from this */
+ − 714 /* loop, rather it computes a schedule from which the in-water portion of the */
+ − 715 /* total phase volume time (Deco_Phase_Volume_Time) can be extracted. Also, */
+ − 716 /* the gas loadings computed at the end of this loop are used the subroutine */
+ − 717 /* which computes the out-of-water portion of the total phase volume time */
+ − 718 /* (Surface_Phase_Volume_Time) for that schedule. */
+ − 719
+ − 720 /* Note that exit is made from the loop after last ascent is made to a deco */
+ − 721 /* stop depth that is less than or equal to zero. A final deco stop less */
+ − 722 /* than zero can happen when the user makes an odd step size change during */
+ − 723 /* ascent - such as specifying a 5 msw step size change at the 3 msw stop! */
+ − 724 /* =============================================================================== */
+ − 725
+ − 726 while(true) /* loop will run continuous there is an break statement */
+ − 727 {
+ − 728 if(starting_depth > deco_stop_depth )
+ − 729 gas_loadings_ascent_descen(helium_pressure, nitrogen_pressure, starting_depth, deco_stop_depth, rate,first_stop);
+ − 730
+ − 731 first_stop = false;
+ − 732 if (deco_stop_depth <= 0.0f)
+ − 733 {
+ − 734 break;
+ − 735 }
+ − 736 if (number_of_changes > 1)
+ − 737 {
+ − 738 int i1 = number_of_changes;
+ − 739 for (i = 2; i <= i1; ++i) {
+ − 740 if (depth_change[i - 1] >= deco_stop_depth)
+ − 741 {
+ − 742 mix_number = mix_change[i - 1];
+ − 743 rate = rate_change[i - 1];
+ − 744 step_size = step_size_change[i - 1];
+ − 745 }
+ − 746 }
+ − 747 }
+ − 748 if(vpm_b)
+ − 749 {
+ − 750 float fist_stop_depth2 = fmaxf(first_stop_depth,max_first_stop_depth);
+ − 751 BOYLES_LAW_COMPENSATION(&fist_stop_depth2, &deco_stop_depth, &step_size);
+ − 752 }
+ − 753 decompression_stop(&deco_stop_depth, &step_size, false);
+ − 754 starting_depth = deco_stop_depth;
+ − 755
+ − 756 if(deco_stop_depth == (float)pDiveSettings->last_stop_depth_bar * 10)
+ − 757 deco_stop_depth = 0;
+ − 758 else
+ − 759 {
+ − 760 deco_stop_depth = deco_stop_depth - step_size;
+ − 761 deco_stop_depth = fmaxf(deco_stop_depth,(float)pDiveSettings->last_stop_depth_bar * 10);
+ − 762 }
+ − 763
+ − 764 count++;
+ − 765 //if(count > 14)
+ − 766 //return CALC_CRITICAL2;
+ − 767 /* L60: */
+ − 768 }
+ − 769
+ − 770 return vpm_check_converged(calc_nulltime);
+ − 771 }
+ − 772 /* =============================================================================== */
+ − 773 /* COMPUTE TOTAL PHASE VOLUME TIME AND MAKE CRITICAL VOLUME COMPARISON */
+ − 774 /* The deco phase volume time is computed from the run time. The surface */
+ − 775 /* phase volume time is computed in a subroutine based on the surfacing gas */
+ − 776 /* loadings from previous deco loop block. Next the total phase volume time */
+ − 777 /* (in-water + surface) for each compartment is compared against the previous */
+ − 778 /* total phase volume time. The schedule is converged when the difference is */
+ − 779 /* less than or equal to 1 minute in any one of the 16 compartments. */
+ − 780
+ − 781 /* Note: the "phase volume time" is somewhat of a mathematical concept. */
+ − 782 /* It is the time divided out of a total integration of supersaturation */
+ − 783 /* gradient x time (in-water and surface). This integration is multiplied */
+ − 784 /* by the excess bubble number to represent the amount of free-gas released */
+ − 785 /* as a result of allowing a certain number of excess bubbles to form. */
+ − 786 /* =============================================================================== */
+ − 787 /* end of deco stop loop */
+ − 788
290
+ − 789 static int vpm_check_converged(_Bool calc_nulltime)
38
+ − 790 {
+ − 791
+ − 792 short i;
+ − 793 float critical_volume_comparison;
+ − 794 float r1;
+ − 795 _Bool schedule_converged = false;
+ − 796
+ − 797
+ − 798 deco_phase_volume_time = run_time - run_time_start_of_deco_zone;
+ − 799 calc_surface_phase_volume_time();
+ − 800
+ − 801 for (i = 1; i <= 16; ++i)
+ − 802 {
+ − 803 phase_volume_time[i - 1] =
+ − 804 deco_phase_volume_time + surface_phase_volume_time[i - 1];
+ − 805 critical_volume_comparison = (r1 = phase_volume_time[i - 1] - last_phase_volume_time[i - 1], fabs(r1));
+ − 806
+ − 807 if (critical_volume_comparison <= 1.0f)
+ − 808 {
+ − 809 schedule_converged = true;
+ − 810 }
+ − 811 }
+ − 812
+ − 813 /* =============================================================================== */
+ − 814 /* CRITICAL VOLUME DECISION TREE BETWEEN LINES 70 AND 99 */
+ − 815 /* There are two options here. If the Critical Volume Agorithm setting is */
+ − 816 /* "on" and the schedule is converged, or the Critical Volume Algorithm */
+ − 817 /* setting was "off" in the first place, the program will re-assign variables */
+ − 818 /* to their values at the start of ascent (end of bottom time) and process */
+ − 819 /* a complete decompression schedule once again using all the same ascent */
+ − 820 /* parameters and first stop depth. This decompression schedule will match */
+ − 821 /* the last iteration of the Critical Volume Loop and the program will write */
+ − 822 /* the final deco schedule to the output file. */
+ − 823
+ − 824 /* Note: if the Critical Volume Agorithm setting was "off", the final deco */
+ − 825 /* schedule will be based on "Initial Allowable Supersaturation Gradients." */
+ − 826 /* If it was "on", the final schedule will be based on "Adjusted Allowable */
+ − 827 /* Supersaturation Gradients" (gradients that are "relaxed" as a result of */
+ − 828 /* the Critical Volume Algorithm). */
+ − 829
+ − 830 /* If the Critical Volume Agorithm setting is "on" and the schedule is not */
+ − 831 /* converged, the program will re-assign variables to their values at the */
+ − 832 /* start of the deco zone and process another trial decompression schedule. */
+ − 833 /* =============================================================================== */
+ − 834 /* L70: */
+ − 835 //Not more than 4 iteration allowed
+ − 836 count_critical_volume_iteration++;
+ − 837 if(count_critical_volume_iteration > 4)
+ − 838 {
+ − 839 //return CALC_FINAL_DECO;
+ − 840 if(calc_nulltime)
+ − 841 return CALC_FINAL_DECO;
+ − 842 else
+ − 843 return vpm_calc_final_deco(true);
+ − 844 }
+ − 845 if (schedule_converged || critical_volume_algorithm_off)
+ − 846 {
+ − 847
+ − 848 //return CALC_FINAL_DECO;
+ − 849 if(calc_nulltime)
+ − 850 return CALC_FINAL_DECO;
+ − 851 else
+ − 852 return vpm_calc_final_deco(true);
+ − 853 /* final deco schedule */
+ − 854 /* exit critical volume l */
+ − 855
+ − 856 /* =============================================================================== */
+ − 857 /* IF SCHEDULE NOT CONVERGED, COMPUTE RELAXED ALLOWABLE SUPERSATURATION */
+ − 858 /* GRADIENTS WITH VPM CRITICAL VOLUME ALGORITHM AND PROCESS ANOTHER */
+ − 859 /* ITERATION OF THE CRITICAL VOLUME LOOP */
+ − 860 /* =============================================================================== */
+ − 861
+ − 862 } else {
+ − 863 critical_volume(&deco_phase_volume_time);
+ − 864 deco_phase_volume_time = 0.;
+ − 865 run_time = run_time_start_of_deco_calc;
+ − 866 starting_depth = depth_start_of_deco_calc;
+ − 867 mix_number = mix_change[0];
+ − 868 rate = rate_change[0];
+ − 869 step_size = step_size_change[0];
+ − 870 for (i = 1; i <= 16; ++i)
+ − 871 {
+ − 872 last_phase_volume_time[i - 1] = phase_volume_time[i - 1];
+ − 873 helium_pressure[i - 1] = he_pressure_start_of_deco_zone[i - 1];
+ − 874 nitrogen_pressure[i - 1] = n2_pressure_start_of_deco_zone[i - 1];
+ − 875 }
+ − 876 if(calc_nulltime)
+ − 877 return CALC_CRITICAL;
+ − 878 else
+ − 879 return vpm_calc_critcal_volume(true, false);
+ − 880 }
+ − 881 /* end of critical volume decision */
+ − 882 /* L100: */
+ − 883 // }/* end of critical vol loop */
+ − 884 }
+ − 885
290
+ − 886 static void vpm_calc_deco_ceiling(void)
38
+ − 887 {
+ − 888
+ − 889 short i;
+ − 890 // hw 1601209 float r1;
+ − 891 // hw 1601209 float stop_time;
+ − 892 // hw 1601209 int count = 0;
+ − 893 //static int dp_max;
+ − 894 //static float surfacetime;
+ − 895 // _Bool first_stop = false;
+ − 896 float tissue_He_saturation[16];
+ − 897 float tissue_N2_saturation[16];
+ − 898 float vpm_buehlmann_safety_gradient = 1.0f - (((float)pDiveSettings->vpm_conservatism) / 40);
+ − 899 //max_first_stop_depth = fmaxf(first_stop_depth,max_first_stop_depth);
+ − 900
+ − 901 /** CALC DECO Ceiling ******************************************************************/
+ − 902 /** Not when Future stops */
+ − 903 if(vpm_calc_what == DECOSTOPS)
+ − 904 {
+ − 905
+ − 906 for (i = 1; i <= 16; ++i)
+ − 907 {
+ − 908 helium_pressure[i - 1] = he_pressure_start_of_deco_zone[i - 1];
+ − 909 nitrogen_pressure[i - 1] = n2_pressure_start_of_deco_zone[i - 1];
+ − 910 }
+ − 911 run_time = run_time_start_of_ascent;// run_time_start_of_ascent;
+ − 912 starting_depth = depth_change[0];
+ − 913 mix_number = mix_change[0];
+ − 914 rate = rate_change[0];
+ − 915 //gas_loadings_ascent_descen(helium_pressure,nitrogen_pressure, starting_depth, depth_start_of_deco_calc, rate, true);
+ − 916
+ − 917 float deco_ceiling_depth = 0.0f;
+ − 918 if(depth_start_of_deco_calc > max_deco_ceiling_depth)
+ − 919 {
+ − 920 calc_deco_ceiling(&deco_ceiling_depth, true);
+ − 921 }
+ − 922 if(buehlmannSafety)
+ − 923 {
+ − 924 for (i = 0; i < 16; i++)
+ − 925 {
+ − 926 tissue_He_saturation[i] = helium_pressure[i] / 10;
+ − 927 tissue_N2_saturation[i] = nitrogen_pressure[i] / 10;
+ − 928 }
+ − 929
+ − 930 if(!decom_tissue_test_tolerance(tissue_N2_saturation, tissue_He_saturation, vpm_buehlmann_safety_gradient, (deco_ceiling_depth / 10.0f) + pInput->pressure_surface_bar))
+ − 931 {
+ − 932
+ − 933 vpm_violates_buehlmann = true;
+ − 934 do {
+ − 935 deco_ceiling_depth += 0.1f;
+ − 936 } while (!decom_tissue_test_tolerance(tissue_N2_saturation, tissue_He_saturation, vpm_buehlmann_safety_gradient, (deco_ceiling_depth / 10.0f) + pInput->pressure_surface_bar));
+ − 937 }
+ − 938 }
+ − 939
+ − 940 if (deco_ceiling_depth < depth_start_of_deco_calc)
+ − 941 {
+ − 942 projected_ascent(&depth_start_of_deco_calc, &rate, &deco_ceiling_depth, &step_size);
+ − 943 }
+ − 944
+ − 945 max_deco_ceiling_depth = fmaxf(max_deco_ceiling_depth,deco_ceiling_depth);
+ − 946
+ − 947 if(depth_start_of_deco_calc > deco_ceiling_depth)
+ − 948 {
+ − 949 gas_loadings_ascent_descen(helium_pressure,nitrogen_pressure, depth_start_of_deco_calc,deco_ceiling_depth, rate, true);
+ − 950 //surfacetime += segment_time;
+ − 951 }
+ − 952
+ − 953 if(vpm_b)
+ − 954 {
+ − 955 BOYLES_LAW_COMPENSATION(&max_deco_ceiling_depth, &deco_ceiling_depth, &step_size);
+ − 956 }
+ − 957 calc_deco_ceiling(&deco_ceiling_depth, false);
+ − 958
+ − 959 // buehlmann safety
+ − 960 if(vpm_violates_buehlmann)
+ − 961 {
+ − 962 for (i = 0; i < 16; i++)
+ − 963 {
+ − 964 tissue_He_saturation[i] = helium_pressure[i] / 10;
+ − 965 tissue_N2_saturation[i] = nitrogen_pressure[i] / 10;
+ − 966 }
+ − 967
+ − 968 if(!decom_tissue_test_tolerance(tissue_N2_saturation, tissue_He_saturation, vpm_buehlmann_safety_gradient, (deco_ceiling_depth / 10.0f) + pInput->pressure_surface_bar))
+ − 969 {
+ − 970
+ − 971 vpm_violates_buehlmann = true;
+ − 972 do {
+ − 973 deco_ceiling_depth += 0.1f;
+ − 974 } while (!decom_tissue_test_tolerance(tissue_N2_saturation, tissue_He_saturation, vpm_buehlmann_safety_gradient, (deco_ceiling_depth / 10.0f) + pInput->pressure_surface_bar));
+ − 975 }
+ − 976 }
+ − 977 // output_ceiling_meter
+ − 978 if(deco_ceiling_depth > first_stop_depth)
+ − 979 deco_ceiling_depth = first_stop_depth;
+ − 980 pDecoInfo->output_ceiling_meter = deco_ceiling_depth ;
+ − 981 }
+ − 982 else
+ − 983 {
+ − 984 pDecoInfo->output_ceiling_meter = 0;
+ − 985 }
+ − 986
+ − 987 // fix hw 160627
+ − 988 if(pDecoInfo->output_ceiling_meter < 0)
+ − 989 pDecoInfo->output_ceiling_meter = 0;
+ − 990
+ − 991 /*** End CALC ceiling ***************************************************/
+ − 992 }
+ − 993
+ − 994
+ − 995 /* =============================================================================== */
+ − 996 /* DECO STOP LOOP BLOCK FOR FINAL DECOMPRESSION SCHEDULE */
+ − 997 /* =============================================================================== */
+ − 998
290
+ − 999 static int vpm_calc_final_deco(_Bool begin)
38
+ − 1000 {
+ − 1001 short i;
+ − 1002 float r1;
+ − 1003 float stop_time;
+ − 1004 int count = 0;
+ − 1005 static int dp_max;
+ − 1006 static float surfacetime;
+ − 1007 _Bool first_stop = false;
+ − 1008 max_first_stop_depth = fmaxf(first_stop_depth,max_first_stop_depth);
+ − 1009 if(begin)
+ − 1010 {
+ − 1011 gCNS_VPM = 0;
+ − 1012 dp_max = 0;
+ − 1013 for (i = 1; i <= 16; ++i)
+ − 1014 {
+ − 1015 helium_pressure[i - 1] =
+ − 1016 he_pressure_start_of_ascent[i - 1];
+ − 1017 nitrogen_pressure[i - 1] =
+ − 1018 n2_pressure_start_of_ascent[i - 1];
+ − 1019 }
+ − 1020 run_time = run_time_start_of_ascent;// run_time_start_of_ascent;
+ − 1021 starting_depth = depth_change[0];
+ − 1022 mix_number = mix_change[0];
+ − 1023 rate = rate_change[0];
+ − 1024 step_size = step_size_change[0];
+ − 1025 deco_stop_depth = first_stop_depth;
+ − 1026 max_first_stop_depth = fmaxf(first_stop_depth,max_first_stop_depth);
+ − 1027 last_run_time = 0.;
+ − 1028
+ − 1029
+ − 1030
+ − 1031 /* =============================================================================== */
+ − 1032 /* DECO STOP LOOP BLOCK FOR FINAL DECOMPRESSION SCHEDULE */
+ − 1033 /* =============================================================================== */
+ − 1034 surfacetime = 0;
+ − 1035 first_stop = true;
+ − 1036 }
+ − 1037
+ − 1038 while(true) /* loop will run continuous until there is an break statement */
+ − 1039 {
+ − 1040 if(starting_depth > deco_stop_depth)
+ − 1041 {
+ − 1042 gas_loadings_ascent_descen(helium_pressure,nitrogen_pressure, starting_depth,deco_stop_depth, rate, first_stop);
+ − 1043 surfacetime += segment_time;
+ − 1044 }
+ − 1045
+ − 1046 /* =============================================================================== */
+ − 1047 /* DURING FINAL DECOMPRESSION SCHEDULE PROCESS, COMPUTE MAXIMUM ACTUAL */
+ − 1048 /* SUPERSATURATION GRADIENT RESULTING IN EACH COMPARTMENT */
+ − 1049 /* If there is a repetitive dive, this will be used later in the VPM */
+ − 1050 /* Repetitive Algorithm to adjust the values for critical radii. */
+ − 1051 /* =============================================================================== */
+ − 1052 if(vpm_calc_what == DECOSTOPS)
+ − 1053 calc_max_actual_gradient(&deco_stop_depth);
+ − 1054
+ − 1055 if (deco_stop_depth <= 0.0f) {
+ − 1056 break;
+ − 1057 }
+ − 1058 if (number_of_changes > 1)
+ − 1059 {
+ − 1060 int i1 = number_of_changes;
+ − 1061 for (i = 2; i <= i1; ++i)
+ − 1062 {
+ − 1063 if (depth_change[i - 1] >= deco_stop_depth)
+ − 1064 {
+ − 1065 mix_number = mix_change[i - 1];
+ − 1066 rate = rate_change[i - 1];
+ − 1067 step_size = step_size_change[i - 1];
+ − 1068 }
+ − 1069 }
+ − 1070 }
+ − 1071
+ − 1072 if(first_stop)
+ − 1073 {
+ − 1074 run_time_first_stop = run_time;
+ − 1075 first_stop = false;
+ − 1076 }
+ − 1077 if(vpm_b)
+ − 1078 {
+ − 1079 BOYLES_LAW_COMPENSATION(&max_first_stop_depth, &deco_stop_depth, &step_size);
+ − 1080 }
+ − 1081 decompression_stop(&deco_stop_depth, &step_size, true);
+ − 1082
+ − 1083 /* =============================================================================== */
+ − 1084 /* This next bit justs rounds up the stop time at the first stop to be in */
+ − 1085 /* whole increments of the minimum stop time (to make for a nice deco table). */
+ − 1086 /* =============================================================================== */
+ − 1087
+ − 1088 if (last_run_time == 0.0f)
+ − 1089 {
+ − 1090 r1 = segment_time / minimum_deco_stop_time + 0.5f;
+ − 1091 stop_time = r_int(&r1) * minimum_deco_stop_time;
+ − 1092 } else {
+ − 1093 stop_time = run_time - last_run_time;
+ − 1094 }
+ − 1095 stop_time = segment_time;
+ − 1096 surfacetime += stop_time;
+ − 1097 if((vpm_calc_what == DECOSTOPS) || (vpm_calc_what == BAILOUTSTOPS))
+ − 1098 {
+ − 1099 int dp = 0;
+ − 1100 if(deco_stop_depth == (float)pDiveSettings->last_stop_depth_bar * 10)
+ − 1101 {
+ − 1102 dp = 0;
+ − 1103 }
+ − 1104 else
+ − 1105 {
+ − 1106 dp = 1 + (int)((deco_stop_depth - (pDiveSettings->input_second_to_last_stop_depth_bar * 10)) / step_size);
+ − 1107 }
+ − 1108 dp_max = (int)fmaxf(dp_max,dp);
+ − 1109 if(dp < DECOINFO_STRUCT_MAX_STOPS)
+ − 1110 {
+ − 1111 int stop_time_seconds = fminf((999 * 60), (int)(stop_time *60));
+ − 1112 //
+ − 1113
+ − 1114 //if(vpm_calc_what == DECOSTOPS)
+ − 1115 pDecoInfo->output_stop_length_seconds[dp] = (unsigned short)stop_time_seconds;
+ − 1116 //else
+ − 1117 //decostop_bailout[dp] = (unsigned short)stop_time_seconds;
+ − 1118 }
+ − 1119 }
+ − 1120
+ − 1121
+ − 1122 /* =============================================================================== */
+ − 1123 /* DURING FINAL DECOMPRESSION SCHEDULE, IF MINIMUM STOP TIME PARAMETER IS A */
+ − 1124 /* WHOLE NUMBER (i.e. 1 minute) THEN WRITE DECO SCHEDULE USING short */
+ − 1125 /* NUMBERS (looks nicer). OTHERWISE, USE DECIMAL NUMBERS. */
+ − 1126 /* Note: per the request of a noted exploration diver(!), program now allows */
+ − 1127 /* a minimum stop time of less than one minute so that total ascent time can */
+ − 1128 /* be minimized on very long dives. In fact, with step size set at 1 fsw or */
+ − 1129 /* 0.2 msw and minimum stop time set at 0.1 minute (6 seconds), a near */
+ − 1130 /* continuous decompression schedule can be computed. */
+ − 1131 /* =============================================================================== */
+ − 1132
+ − 1133 starting_depth = deco_stop_depth;
+ − 1134 if(deco_stop_depth == (float)pDiveSettings->last_stop_depth_bar * 10)
+ − 1135 deco_stop_depth = 0;
+ − 1136 else
+ − 1137 {
+ − 1138 deco_stop_depth = deco_stop_depth - step_size;
+ − 1139 deco_stop_depth = fmaxf(deco_stop_depth,(float)pDiveSettings->last_stop_depth_bar * 10);
+ − 1140 }
+ − 1141
+ − 1142 last_run_time = run_time;
+ − 1143 count++;
+ − 1144 //if(count > 14)
+ − 1145 //return CALC_FINAL_DECO2;
+ − 1146 /* L80: */
+ − 1147 } /* for final deco sche */
+ − 1148
+ − 1149 if( (vpm_calc_what == DECOSTOPS) || (vpm_calc_what == BAILOUTSTOPS))
+ − 1150 {
+ − 1151 for(int dp = dp_max +1;dp < DECOINFO_STRUCT_MAX_STOPS;dp++)
+ − 1152 {
+ − 1153 //if(vpm_calc_what == DECOSTOPS)
+ − 1154 pDecoInfo->output_stop_length_seconds[dp] = 0;
+ − 1155 //else
+ − 1156 //decostop_bailout[dp] = 0;
+ − 1157 }
+ − 1158 }
+ − 1159 pDecoInfo->output_time_to_surface_seconds = (int)(surfacetime * 60);
+ − 1160 pDecoInfo->output_ndl_seconds = 0;
+ − 1161
+ − 1162 vpm_calc_deco_ceiling();
+ − 1163 /* end of deco stop lo */
+ − 1164 return CALC_END;
+ − 1165 }
+ − 1166
+ − 1167 /* =============================================================================== */
+ − 1168 /* SUBROUTINE NUCLEAR_REGENERATION */
+ − 1169 /* Purpose: This subprogram calculates the regeneration of VPM critical */
+ − 1170 /* radii that takes place over the dive time. The regeneration time constant */
+ − 1171 /* has a time scale of weeks so this will have very little impact on dives of */
+ − 1172 /* normal length, but will have a major impact for saturation dives. */
+ − 1173 /* =============================================================================== */
+ − 1174
290
+ − 1175 static int nuclear_regeneration(float *dive_time)
38
+ − 1176 {
+ − 1177 /* Local variables */
+ − 1178 float crush_pressure_adjust_ratio_he,
+ − 1179 ending_radius_n2,
+ − 1180 ending_radius_he;
+ − 1181 short i;
+ − 1182 float crushing_pressure_pascals_n2,
+ − 1183 crushing_pressure_pascals_he,
+ − 1184 adj_crush_pressure_n2_pascals,
+ − 1185 adj_crush_pressure_he_pascals,
+ − 1186 crush_pressure_adjust_ratio_n2;
+ − 1187
+ − 1188 /* loop */
+ − 1189 /* =============================================================================== */
+ − 1190 /* CALCULATIONS */
+ − 1191 /* First convert the maximum crushing pressure obtained for each compartment */
+ − 1192 /* to Pascals. Next, compute the ending radius for helium and nitrogen */
+ − 1193 /* critical nuclei in each compartment. */
+ − 1194 /* =============================================================================== */
+ − 1195
+ − 1196 for (i = 1; i <= 16; ++i)
+ − 1197 {
+ − 1198 crushing_pressure_pascals_he =
+ − 1199 pVpm->max_crushing_pressure_he[i - 1] / UNITS_FACTOR * 101325.0f;
+ − 1200 crushing_pressure_pascals_n2 =
+ − 1201 pVpm->max_crushing_pressure_n2[i - 1] / UNITS_FACTOR * 101325.0f;
+ − 1202 ending_radius_he =
+ − 1203 1.0f / (crushing_pressure_pascals_he /
+ − 1204 ((SKIN_COMPRESSION_GAMMAC - SURFACE_TENSION_GAMMA) * 2.0f) +
+ − 1205 1.0f / pVpm->adjusted_critical_radius_he[i - 1]);
+ − 1206 ending_radius_n2 =
+ − 1207 1.0f / (crushing_pressure_pascals_n2 /
+ − 1208 ((SKIN_COMPRESSION_GAMMAC - SURFACE_TENSION_GAMMA) * 2.0f) +
+ − 1209 1.0f / pVpm->adjusted_critical_radius_n2[i - 1]);
+ − 1210
+ − 1211 /* =============================================================================== */
+ − 1212 /* A "regenerated" radius for each nucleus is now calculated based on the */
+ − 1213 /* regeneration time constant. This means that after application of */
+ − 1214 /* crushing pressure and reduction in radius, a nucleus will slowly grow */
+ − 1215 /* back to its original initial radius over a period of time. This */
+ − 1216 /* phenomenon is probabilistic in nature and depends on absolute temperature. */
+ − 1217 /* It is independent of crushing pressure. */
+ − 1218 /* =============================================================================== */
+ − 1219
+ − 1220 regenerated_radius_he[i - 1] =
+ − 1221 pVpm->adjusted_critical_radius_he[i - 1] +
+ − 1222 (ending_radius_he - pVpm->adjusted_critical_radius_he[i - 1]) *
+ − 1223 expf(-(*dive_time) / REGENERATION_TIME_CONSTANT);
+ − 1224 regenerated_radius_n2[i - 1] =
+ − 1225 pVpm->adjusted_critical_radius_n2[i - 1] +
+ − 1226 (ending_radius_n2 - pVpm->adjusted_critical_radius_n2[i - 1]) *
+ − 1227 expf(-(*dive_time) / REGENERATION_TIME_CONSTANT);
+ − 1228
+ − 1229 /* =============================================================================== */
+ − 1230 /* In order to preserve reference back to the initial critical radii after */
+ − 1231 /* regeneration, an "adjusted crushing pressure" for the nuclei in each */
+ − 1232 /* compartment must be computed. In other words, this is the value of */
+ − 1233 /* crushing pressure that would have reduced the original nucleus to the */
+ − 1234 /* to the present radius had regeneration not taken place. The ratio */
+ − 1235 /* for adjusting crushing pressure is obtained from algebraic manipulation */
+ − 1236 /* of the standard VPM equations. The adjusted crushing pressure, in lieu */
+ − 1237 /* of the original crushing pressure, is then applied in the VPM Critical */
+ − 1238 /* Volume Algorithm and the VPM Repetitive Algorithm. */
+ − 1239 /* =============================================================================== */
+ − 1240
+ − 1241 crush_pressure_adjust_ratio_he =
+ − 1242 ending_radius_he * (pVpm->adjusted_critical_radius_he[i - 1] -
+ − 1243 regenerated_radius_he[i - 1]) /
+ − 1244 (regenerated_radius_he[i - 1] *
+ − 1245 (pVpm->adjusted_critical_radius_he[i - 1] -
+ − 1246 ending_radius_he));
+ − 1247 crush_pressure_adjust_ratio_n2 =
+ − 1248 ending_radius_n2 * (pVpm->adjusted_critical_radius_n2[i - 1] -
+ − 1249 regenerated_radius_n2[i - 1]) /
+ − 1250 (regenerated_radius_n2[i - 1] *
+ − 1251 (pVpm->adjusted_critical_radius_n2[i - 1] -
+ − 1252 ending_radius_n2));
+ − 1253 adj_crush_pressure_he_pascals =
+ − 1254 crushing_pressure_pascals_he * crush_pressure_adjust_ratio_he;
+ − 1255 adj_crush_pressure_n2_pascals =
+ − 1256 crushing_pressure_pascals_n2 * crush_pressure_adjust_ratio_n2;
+ − 1257 pVpm->adjusted_crushing_pressure_he[i - 1] =
+ − 1258 adj_crush_pressure_he_pascals / 101325.0f * UNITS_FACTOR;
+ − 1259 pVpm->adjusted_crushing_pressure_n2[i - 1] =
+ − 1260 adj_crush_pressure_n2_pascals / 101325.0f * UNITS_FACTOR;
+ − 1261 }
+ − 1262 return 0;
+ − 1263 } /* nuclear_regeneration */
+ − 1264
+ − 1265 /* =============================================================================== */
+ − 1266 /* SUBROUTINE CALC_INITIAL_ALLOWABLE_GRADIENT */
+ − 1267 /* Purpose: This subprogram calculates the initial allowable gradients for */
+ − 1268 /* helium and nitrogren in each compartment. These are the gradients that */
+ − 1269 /* will be used to set the deco ceiling on the first pass through the deco */
+ − 1270 /* loop. If the Critical Volume Algorithm is set to "off", then these */
+ − 1271 /* gradients will determine the final deco schedule. Otherwise, if the */
+ − 1272 /* Critical Volume Algorithm is set to "on", these gradients will be further */
+ − 1273 /* "relaxed" by the Critical Volume Algorithm subroutine. The initial */
+ − 1274 /* allowable gradients are referred to as "PssMin" in the papers by Yount */
+ − 1275 /* and colleauges, i.e., the minimum supersaturation pressure gradients */
+ − 1276 /* that will probe bubble formation in the VPM nuclei that started with the */
+ − 1277 /* designated minimum initial radius (critical radius). */
+ − 1278
+ − 1279 /* The initial allowable gradients are computed directly from the */
+ − 1280 /* "regenerated" radii after the Nuclear Regeneration subroutine. These */
+ − 1281 /* gradients are tracked separately for helium and nitrogen. */
+ − 1282 /* =============================================================================== */
+ − 1283
290
+ − 1284 static int calc_initial_allowable_gradient()
38
+ − 1285 {
+ − 1286 float initial_allowable_grad_n2_pa,
+ − 1287 initial_allowable_grad_he_pa;
+ − 1288 short i;
+ − 1289
+ − 1290 /* loop */
+ − 1291 /* =============================================================================== */
+ − 1292 /* CALCULATIONS */
+ − 1293 /* The initial allowable gradients are computed in Pascals and then converted */
+ − 1294 /* to the diving pressure units. Two different sets of arrays are used to */
+ − 1295 /* save the calculations - Initial Allowable Gradients and Allowable */
+ − 1296 /* Gradients. The Allowable Gradients are assigned the values from Initial */
+ − 1297 /* Allowable Gradients however the Allowable Gradients can be changed later */
+ − 1298 /* by the Critical Volume subroutine. The values for the Initial Allowable */
+ − 1299 /* Gradients are saved in a global array for later use by both the Critical */
+ − 1300 /* Volume subroutine and the VPM Repetitive Algorithm subroutine. */
+ − 1301 /* =============================================================================== */
+ − 1302
+ − 1303 for (i = 1; i <= 16; ++i)
+ − 1304 {
+ − 1305 initial_allowable_grad_n2_pa =
+ − 1306 SURFACE_TENSION_GAMMA * 2.0f *
+ − 1307 (SKIN_COMPRESSION_GAMMAC - SURFACE_TENSION_GAMMA) /
+ − 1308 (regenerated_radius_n2[i - 1] * SKIN_COMPRESSION_GAMMAC);
+ − 1309
+ − 1310 initial_allowable_grad_he_pa =
+ − 1311 SURFACE_TENSION_GAMMA * 2.0f *
+ − 1312 (SKIN_COMPRESSION_GAMMAC - SURFACE_TENSION_GAMMA) /
+ − 1313 (regenerated_radius_he[i - 1] * SKIN_COMPRESSION_GAMMAC);
+ − 1314
+ − 1315 pVpm->initial_allowable_gradient_n2[i - 1] =
+ − 1316 initial_allowable_grad_n2_pa / 101325.0f * UNITS_FACTOR;
+ − 1317
+ − 1318 pVpm->initial_allowable_gradient_he[i - 1] =
+ − 1319 initial_allowable_grad_he_pa / 101325.0f * UNITS_FACTOR;
+ − 1320
+ − 1321 allowable_gradient_he[i - 1] =
+ − 1322 pVpm->initial_allowable_gradient_he[i - 1];
+ − 1323
+ − 1324 allowable_gradient_n2[i - 1] =
+ − 1325 pVpm->initial_allowable_gradient_n2[i - 1];
+ − 1326 }
+ − 1327 return 0;
+ − 1328 } /* calc_initial_allowable_gradient */
+ − 1329
+ − 1330 /* =============================================================================== */
+ − 1331 /* SUBROUTINE CALC_DECO_CEILING */
+ − 1332 /* Purpose: This subprogram calculates the deco ceiling (the safe ascent */
+ − 1333 /* depth) in each compartment, based on the allowable gradients, and then */
+ − 1334 /* finds the deepest deco ceiling across all compartments. This deepest */
+ − 1335 /* value (Deco Ceiling Depth) is then used by the Decompression Stop */
+ − 1336 /* subroutine to determine the actual deco schedule. */
+ − 1337 /* =============================================================================== */
+ − 1338
290
+ − 1339 static int calc_deco_ceiling(float *deco_ceiling_depth,_Bool fallowable)
38
+ − 1340 {
+ − 1341 /* System generated locals */
+ − 1342 float r1, r2;
+ − 1343 /* Local variables */
+ − 1344 float weighted_allowable_gradient;
+ − 1345 short i;
+ − 1346 float compartment_deco_ceiling[16],
+ − 1347 gas_loading,
+ − 1348 tolerated_ambient_pressure;
+ − 1349 float gradient_he, gradient_n2;
+ − 1350
+ − 1351 if(!vpm_b)
+ − 1352 fallowable = true;
+ − 1353 /* loop */
+ − 1354 /* =============================================================================== */
+ − 1355 /* CALCULATIONS */
+ − 1356 /* Since there are two sets of allowable gradients being tracked, one for */
+ − 1357 /* helium and one for nitrogen, a "weighted allowable gradient" must be */
+ − 1358 /* computed each time based on the proportions of helium and nitrogen in */
+ − 1359 /* each compartment. This proportioning follows the methodology of */
+ − 1360 /* Buhlmann/Keller. If there is no helium and nitrogen in the compartment, */
+ − 1361 /* such as after extended periods of oxygen breathing, then the minimum value */
+ − 1362 /* across both gases will be used. It is important to note that if a */
+ − 1363 /* compartment is empty of helium and nitrogen, then the weighted allowable */
+ − 1364 /* gradient formula cannot be used since it will result in division by zero. */
+ − 1365 /* =============================================================================== */
+ − 1366
+ − 1367 for (i = 1; i <= 16; ++i)
+ − 1368 {
+ − 1369
+ − 1370 // abfrage raus und pointer stattdessen
+ − 1371 if(fallowable){
+ − 1372 gradient_he = allowable_gradient_he[i-1];
+ − 1373 gradient_n2 = allowable_gradient_n2[i-1];
+ − 1374 }
+ − 1375 else{
+ − 1376 gradient_he = deco_gradient_he[i-1];
+ − 1377 gradient_n2 = deco_gradient_n2[i-1];
+ − 1378 }
+ − 1379
+ − 1380 gas_loading = helium_pressure[i - 1] + nitrogen_pressure[i - 1];
+ − 1381
+ − 1382 if (gas_loading > 0)
+ − 1383 {
+ − 1384 weighted_allowable_gradient =
+ − 1385 (gradient_he * helium_pressure[i - 1] +
+ − 1386 gradient_n2 * nitrogen_pressure[i - 1]) /
+ − 1387 (helium_pressure[i - 1] + nitrogen_pressure[i - 1]);
+ − 1388
+ − 1389 tolerated_ambient_pressure =
+ − 1390 gas_loading +
+ − 1391 CONSTANT_PRESSURE_OTHER_GASES -
+ − 1392 weighted_allowable_gradient;
+ − 1393 }
+ − 1394 else
+ − 1395 {
+ − 1396 /* Computing MIN */
+ − 1397 r1 = gradient_he;
+ − 1398 r2 = gradient_n2;
+ − 1399 weighted_allowable_gradient = fminf(r1,r2);
+ − 1400
+ − 1401 tolerated_ambient_pressure =
+ − 1402 CONSTANT_PRESSURE_OTHER_GASES - weighted_allowable_gradient;
+ − 1403 }
+ − 1404
+ − 1405 /* =============================================================================== */
+ − 1406 /* The tolerated ambient pressure cannot be less than zero absolute, i.e., */
+ − 1407 /* the vacuum of outer space! */
+ − 1408 /* =============================================================================== */
+ − 1409
+ − 1410 if (tolerated_ambient_pressure < 0) {
+ − 1411 tolerated_ambient_pressure = 0;
+ − 1412 }
+ − 1413 compartment_deco_ceiling[i - 1] =
+ − 1414 tolerated_ambient_pressure - barometric_pressure;
+ − 1415 }
+ − 1416
+ − 1417 /* =============================================================================== */
+ − 1418 /* The Deco Ceiling Depth is computed in a loop after all of the individual */
+ − 1419 /* compartment deco ceilings have been calculated. It is important that the */
+ − 1420 /* Deco Ceiling Depth (max deco ceiling across all compartments) only be */
+ − 1421 /* extracted from the compartment values and not be compared against some */
+ − 1422 /* initialization value. For example, if MAX(Deco_Ceiling_Depth . .) was */
+ − 1423 /* compared against zero, this could cause a program lockup because sometimes */
+ − 1424 /* the Deco Ceiling Depth needs to be negative (but not less than zero */
+ − 1425 /* absolute ambient pressure) in order to decompress to the last stop at zero */
+ − 1426 /* depth. */
+ − 1427 /* =============================================================================== */
+ − 1428
+ − 1429 *deco_ceiling_depth = compartment_deco_ceiling[0];
+ − 1430 for (i = 2; i <= 16; ++i)
+ − 1431 {
+ − 1432 /* Computing MAX */
+ − 1433 r1 = *deco_ceiling_depth;
+ − 1434 r2 = compartment_deco_ceiling[i - 1];
+ − 1435 *deco_ceiling_depth = fmaxf(r1,r2);
+ − 1436 }
+ − 1437 return 0;
+ − 1438 } /* calc_deco_ceiling */
+ − 1439
+ − 1440
+ − 1441
+ − 1442 /* =============================================================================== */
+ − 1443 /* SUBROUTINE CALC_MAX_ACTUAL_GRADIENT */
+ − 1444 /* Purpose: This subprogram calculates the actual supersaturation gradient */
+ − 1445 /* obtained in each compartment as a result of the ascent profile during */
+ − 1446 /* decompression. Similar to the concept with crushing pressure, the */
+ − 1447 /* supersaturation gradients are not cumulative over a multi-level, staged */
+ − 1448 /* ascent. Rather, it will be the maximum value obtained in any one discrete */
+ − 1449 /* step of the overall ascent. Thus, the program must compute and store the */
+ − 1450 /* maximum actual gradient for each compartment that was obtained across all */
+ − 1451 /* steps of the ascent profile. This subroutine is invoked on the last pass */
+ − 1452 /* through the deco stop loop block when the final deco schedule is being */
+ − 1453 /* generated. */
+ − 1454 /* */
+ − 1455 /* The max actual gradients are later used by the VPM Repetitive Algorithm to */
+ − 1456 /* determine if adjustments to the critical radii are required. If the max */
+ − 1457 /* actual gradient did not exceed the initial alllowable gradient, then no */
+ − 1458 /* adjustment will be made. However, if the max actual gradient did exceed */
+ − 1459 /* the intitial allowable gradient, such as permitted by the Critical Volume */
+ − 1460 /* Algorithm, then the critical radius will be adjusted (made larger) on the */
+ − 1461 /* repetitive dive to compensate for the bubbling that was allowed on the */
+ − 1462 /* previous dive. The use of the max actual gradients is intended to prevent */
+ − 1463 /* the repetitive algorithm from being overly conservative. */
+ − 1464 /* =============================================================================== */
+ − 1465
290
+ − 1466 static int calc_max_actual_gradient(float *deco_stop_depth)
38
+ − 1467 {
+ − 1468 /* System generated locals */
+ − 1469 float r1;
+ − 1470
+ − 1471 /* Local variables */
+ − 1472 short i;
+ − 1473 float compartment_gradient;
+ − 1474
+ − 1475 /* loop */
+ − 1476 /* =============================================================================== */
+ − 1477 /* CALCULATIONS */
+ − 1478 /* Note: negative supersaturation gradients are meaningless for this */
+ − 1479 /* application, so the values must be equal to or greater than zero. */
+ − 1480 /* =============================================================================== */
+ − 1481
+ − 1482 for (i = 1; i <= 16; ++i)
+ − 1483 {
+ − 1484 compartment_gradient =
+ − 1485 helium_pressure[i - 1] +
+ − 1486 nitrogen_pressure[i - 1] +
+ − 1487 CONSTANT_PRESSURE_OTHER_GASES -
+ − 1488 (*deco_stop_depth + barometric_pressure);
+ − 1489 if (compartment_gradient <= 0.0f) {
+ − 1490 compartment_gradient = 0.0f;
+ − 1491 }
+ − 1492 /* Computing MAX */
+ − 1493 r1 = pVpm->max_actual_gradient[i - 1];
+ − 1494 pVpm->max_actual_gradient[i - 1] = fmaxf(r1, compartment_gradient);
+ − 1495 }
+ − 1496 return 0;
+ − 1497 } /* calc_max_actual_gradient */
+ − 1498
+ − 1499 /* =============================================================================== */
+ − 1500 /* SUBROUTINE CALC_SURFACE_PHASE_VOLUME_TIME */
+ − 1501 /* Purpose: This subprogram computes the surface portion of the total phase */
+ − 1502 /* volume time. This is the time factored out of the integration of */
+ − 1503 /* supersaturation gradient x time over the surface interval. The VPM */
+ − 1504 /* considers the gradients that allow bubbles to form or to drive bubble */
+ − 1505 /* growth both in the water and on the surface after the dive. */
+ − 1506
+ − 1507 /* This subroutine is a new development to the VPM algorithm in that it */
+ − 1508 /* computes the time course of supersaturation gradients on the surface */
+ − 1509 /* when both helium and nitrogen are present. Refer to separate write-up */
+ − 1510 /* for a more detailed explanation of this algorithm. */
+ − 1511 /* =============================================================================== */
+ − 1512
290
+ − 1513 static int calc_surface_phase_volume_time()
38
+ − 1514 {
+ − 1515 /* Local variables */
+ − 1516 float decay_time_to_zero_gradient;
+ − 1517 short i;
+ − 1518 float integral_gradient_x_time,
+ − 1519 surface_inspired_n2_pressure;
+ − 1520
+ − 1521 /* loop */
+ − 1522 /* =============================================================================== */
+ − 1523 /* CALCULATIONS */
+ − 1524 /* =============================================================================== */
+ − 1525
+ − 1526 surface_inspired_n2_pressure =
+ − 1527 (barometric_pressure - WATER_VAPOR_PRESSURE) * 0.79f;
+ − 1528 for (i = 1; i <= 16; ++i)
+ − 1529 {
+ − 1530 if (nitrogen_pressure[i - 1] > surface_inspired_n2_pressure)
+ − 1531 {
+ − 1532 surface_phase_volume_time[i - 1] =
+ − 1533 (helium_pressure[i - 1] / HELIUM_TIME_CONSTANT[i - 1] +
+ − 1534 (nitrogen_pressure[i - 1] - surface_inspired_n2_pressure) /
+ − 1535 NITROGEN_TIME_CONSTANT[i - 1]) /
+ − 1536 (helium_pressure[i - 1] + nitrogen_pressure[i - 1] -
+ − 1537 surface_inspired_n2_pressure);
+ − 1538 } else if (nitrogen_pressure[i - 1] <= surface_inspired_n2_pressure &&
+ − 1539 helium_pressure[i - 1] + nitrogen_pressure[i - 1] >= surface_inspired_n2_pressure)
+ − 1540 {
+ − 1541 decay_time_to_zero_gradient =
+ − 1542 1.0f / (NITROGEN_TIME_CONSTANT[i - 1] - HELIUM_TIME_CONSTANT[i - 1]) *
+ − 1543 log((surface_inspired_n2_pressure - nitrogen_pressure[i - 1]) /
+ − 1544 helium_pressure[i - 1]);
+ − 1545 integral_gradient_x_time =
+ − 1546 helium_pressure[i - 1] /
+ − 1547 HELIUM_TIME_CONSTANT[i - 1] *
+ − 1548 (1.0f - expf(-HELIUM_TIME_CONSTANT[i - 1] *
+ − 1549 decay_time_to_zero_gradient)) +
+ − 1550 (nitrogen_pressure[i - 1] - surface_inspired_n2_pressure) /
+ − 1551 NITROGEN_TIME_CONSTANT[i - 1] *
+ − 1552 (1.0f - expf(-NITROGEN_TIME_CONSTANT[i - 1] *
+ − 1553 decay_time_to_zero_gradient));
+ − 1554 surface_phase_volume_time[i - 1] =
+ − 1555 integral_gradient_x_time /
+ − 1556 (helium_pressure[i - 1] +
+ − 1557 nitrogen_pressure[i - 1] -
+ − 1558 surface_inspired_n2_pressure);
+ − 1559 } else {
+ − 1560 surface_phase_volume_time[i - 1] = 0.0f;
+ − 1561 }
+ − 1562 }
+ − 1563 return 0;
+ − 1564 } /* calc_surface_phase_volume_time */
+ − 1565
+ − 1566 /* =============================================================================== */
+ − 1567 /* SUBROUTINE CRITICAL_VOLUME */
+ − 1568 /* Purpose: This subprogram applies the VPM Critical Volume Algorithm. This */
+ − 1569 /* algorithm will compute "relaxed" gradients for helium and nitrogen based */
+ − 1570 /* on the setting of the Critical Volume Parameter Lambda. */
+ − 1571 /* =============================================================================== */
+ − 1572
290
+ − 1573 static int critical_volume(float *deco_phase_volume_time)
38
+ − 1574 {
+ − 1575 /* System generated locals */
+ − 1576 float r1;
+ − 1577
+ − 1578 /* Local variables */
+ − 1579 float initial_allowable_grad_n2_pa,
+ − 1580 initial_allowable_grad_he_pa,
+ − 1581 parameter_lambda_pascals, b,
+ − 1582 c;
+ − 1583 short i;
+ − 1584 float new_allowable_grad_n2_pascals,
+ − 1585 phase_volume_time[16],
+ − 1586 new_allowable_grad_he_pascals,
+ − 1587 adj_crush_pressure_n2_pascals,
+ − 1588 adj_crush_pressure_he_pascals;
+ − 1589
+ − 1590 /* loop */
+ − 1591 /* =============================================================================== */
+ − 1592 /* CALCULATIONS */
+ − 1593 /* Note: Since the Critical Volume Parameter Lambda was defined in units of */
+ − 1594 /* fsw-min in the original papers by Yount and colleauges, the same */
+ − 1595 /* convention is retained here. Although Lambda is adjustable only in units */
+ − 1596 /* of fsw-min in the program settings (range from 6500 to 8300 with default */
+ − 1597 /* 7500), it will convert to the proper value in Pascals-min in this */
+ − 1598 /* subroutine regardless of which diving pressure units are being used in */
+ − 1599 /* the main program - feet of seawater (fsw) or meters of seawater (msw). */
+ − 1600 /* The allowable gradient is computed using the quadratic formula (refer to */
+ − 1601 /* separate write-up posted on the Deco List web site). */
+ − 1602 /* =============================================================================== */
+ − 1603
+ − 1604 /**
+ − 1605 ******************************************************************************
+ − 1606 * @brief critical_volume comment by hw
+ − 1607 * @version V0.0.1
+ − 1608 * @date 19-April-2014
+ − 1609 * @retval global: allowable_gradient_he[i], allowable_gradient_n2[i]
+ − 1610 ******************************************************************************
+ − 1611 */
+ − 1612
+ − 1613 parameter_lambda_pascals =
+ − 1614 CRIT_VOLUME_PARAMETER_LAMBDA / 33.0f * 101325.0f;
+ − 1615 for (i = 1; i <= 16; ++i)
+ − 1616 {
+ − 1617 phase_volume_time[i - 1] =
+ − 1618 *deco_phase_volume_time + surface_phase_volume_time[i - 1];
+ − 1619 }
+ − 1620 for (i = 1; i <= 16; ++i)
+ − 1621 {
+ − 1622
+ − 1623 adj_crush_pressure_he_pascals =
+ − 1624 pVpm->adjusted_crushing_pressure_he[i - 1] / UNITS_FACTOR * 101325.0f;
+ − 1625
+ − 1626 initial_allowable_grad_he_pa =
+ − 1627 pVpm->initial_allowable_gradient_he[i - 1] / UNITS_FACTOR * 101325.0f;
+ − 1628
+ − 1629 b = initial_allowable_grad_he_pa + parameter_lambda_pascals *
+ − 1630 SURFACE_TENSION_GAMMA / (
+ − 1631 SKIN_COMPRESSION_GAMMAC * phase_volume_time[i - 1]);
+ − 1632
+ − 1633 c = SURFACE_TENSION_GAMMA * (
+ − 1634 SURFACE_TENSION_GAMMA * (
+ − 1635 parameter_lambda_pascals * adj_crush_pressure_he_pascals)) /
+ − 1636 (SKIN_COMPRESSION_GAMMAC *
+ − 1637 (SKIN_COMPRESSION_GAMMAC * phase_volume_time[i - 1]));
+ − 1638 /* Computing 2nd power */
+ − 1639
+ − 1640 r1 = b;
+ − 1641
+ − 1642 new_allowable_grad_he_pascals =
+ − 1643 (b + sqrtf(r1 * r1 - c * 4.0f)) / 2.0f;
+ − 1644
+ − 1645 /* modify global variable */
+ − 1646 allowable_gradient_he[i - 1] =
+ − 1647 new_allowable_grad_he_pascals / 101325.0f * UNITS_FACTOR;
+ − 1648 }
+ − 1649
+ − 1650 for (i = 1; i <= 16; ++i)
+ − 1651 {
+ − 1652 adj_crush_pressure_n2_pascals =
+ − 1653 pVpm->adjusted_crushing_pressure_n2[i - 1] / UNITS_FACTOR * 101325.0f;
+ − 1654
+ − 1655 initial_allowable_grad_n2_pa =
+ − 1656 pVpm->initial_allowable_gradient_n2[i - 1] / UNITS_FACTOR * 101325.0f;
+ − 1657
+ − 1658 b = initial_allowable_grad_n2_pa + parameter_lambda_pascals *
+ − 1659 SURFACE_TENSION_GAMMA / (
+ − 1660 SKIN_COMPRESSION_GAMMAC * phase_volume_time[i - 1]);
+ − 1661
+ − 1662 c = SURFACE_TENSION_GAMMA *
+ − 1663 (SURFACE_TENSION_GAMMA *
+ − 1664 (parameter_lambda_pascals * adj_crush_pressure_n2_pascals)) /
+ − 1665 (SKIN_COMPRESSION_GAMMAC *
+ − 1666 (SKIN_COMPRESSION_GAMMAC * phase_volume_time[i - 1]));
+ − 1667 /* Computing 2nd power */
+ − 1668
+ − 1669 r1 = b;
+ − 1670
+ − 1671 new_allowable_grad_n2_pascals =
+ − 1672 (b + sqrtf(r1 * r1 - c * 4.0f)) / 2.0f;
+ − 1673
+ − 1674 /* modify global variable */
+ − 1675 allowable_gradient_n2[i - 1] =
+ − 1676 new_allowable_grad_n2_pascals / 101325.0f * UNITS_FACTOR;
+ − 1677 }
+ − 1678 return 0;
+ − 1679 } /* critical_volume */
+ − 1680
+ − 1681 /* =============================================================================== */
+ − 1682 /* SUBROUTINE CALC_START_OF_DECO_ZONE */
+ − 1683 /* Purpose: This subroutine uses the Bisection Method to find the depth at */
+ − 1684 /* which the leading compartment just enters the decompression zone. */
+ − 1685 /* Source: "Numerical Recipes in Fortran 77", Cambridge University Press, */
+ − 1686 /* 1992. */
+ − 1687 /* =============================================================================== */
+ − 1688
290
+ − 1689 static int calc_start_of_deco_zone(float *starting_depth,
38
+ − 1690 float *rate,
+ − 1691 float *depth_start_of_deco_zone)
+ − 1692 {
+ − 1693 /* Local variables */
+ − 1694 float last_diff_change,
+ − 1695 initial_helium_pressure,
+ − 1696 mid_range_nitrogen_pressure;
+ − 1697 short i, j;
+ − 1698 float initial_inspired_n2_pressure,
+ − 1699 cpt_depth_start_of_deco_zone,
+ − 1700 low_bound,
+ − 1701 initial_inspired_he_pressure,
+ − 1702 high_bound_nitrogen_pressure,
+ − 1703 nitrogen_rate,
+ − 1704 function_at_mid_range,
+ − 1705 function_at_low_bound,
+ − 1706 high_bound,
+ − 1707 mid_range_helium_pressure,
+ − 1708 mid_range_time,
+ − 1709 starting_ambient_pressure,
+ − 1710 initial_nitrogen_pressure,
+ − 1711 function_at_high_bound;
+ − 1712
+ − 1713 float time_to_start_of_deco_zone,
+ − 1714 high_bound_helium_pressure,
+ − 1715 helium_rate,
+ − 1716 differential_change;
+ − 1717 float fraction_helium_begin;
+ − 1718 float fraction_helium_end;
+ − 1719 float fraction_nitrogen_begin;
+ − 1720 float fraction_nitrogen_end;
+ − 1721 float ending_ambient_pressure;
+ − 1722 float time_test;
+ − 1723
+ − 1724
+ − 1725 /* loop */
+ − 1726 /* =============================================================================== */
+ − 1727 /* CALCULATIONS */
+ − 1728 /* First initialize some variables */
+ − 1729 /* =============================================================================== */
+ − 1730
+ − 1731 *depth_start_of_deco_zone = 0.0f;
+ − 1732 starting_ambient_pressure = *starting_depth + barometric_pressure;
+ − 1733
+ − 1734 //>>>>>>>>>>>>>>>>>>>>
+ − 1735 //Test depth to calculate helium_rate and nitrogen_rate
+ − 1736 ending_ambient_pressure = starting_ambient_pressure/2;
+ − 1737
+ − 1738 time_test = (ending_ambient_pressure - starting_ambient_pressure) / *rate;
+ − 1739 decom_get_inert_gases(starting_ambient_pressure / 10, (&pDiveSettings->decogaslist[mix_number]), &fraction_nitrogen_begin, &fraction_helium_begin );
+ − 1740 decom_get_inert_gases(ending_ambient_pressure / 10, (&pDiveSettings->decogaslist[mix_number]), &fraction_nitrogen_end, &fraction_helium_end );
+ − 1741 initial_inspired_he_pressure = (starting_ambient_pressure - WATER_VAPOR_PRESSURE) * fraction_helium_begin;
+ − 1742 initial_inspired_n2_pressure = (starting_ambient_pressure - WATER_VAPOR_PRESSURE) * fraction_nitrogen_begin;
+ − 1743 helium_rate = ((ending_ambient_pressure - WATER_VAPOR_PRESSURE)* fraction_helium_end - initial_inspired_he_pressure)/time_test;
+ − 1744 nitrogen_rate = ((ending_ambient_pressure - WATER_VAPOR_PRESSURE)* fraction_nitrogen_end - initial_inspired_n2_pressure)/time_test;
+ − 1745 //>>>>>>>>>>>>>>>>>>>>>
+ − 1746 /*initial_inspired_he_pressure =
+ − 1747 (starting_ambient_pressure - water_vapor_pressure) *
+ − 1748 fraction_helium[mix_number - 1];
+ − 1749 initial_inspired_n2_pressure =
+ − 1750 (starting_ambient_pressure - water_vapor_pressure) *
+ − 1751 fraction_nitrogen[mix_number - 1];
+ − 1752 helium_rate = *rate * fraction_helium[mix_number - 1];
+ − 1753 nitrogen_rate = *rate * fraction_nitrogen[mix_number - 1];*/
+ − 1754
+ − 1755 /* =============================================================================== */
+ − 1756 /* ESTABLISH THE BOUNDS FOR THE ROOT SEARCH USING THE BISECTION METHOD */
+ − 1757 /* AND CHECK TO MAKE SURE THAT THE ROOT WILL BE WITHIN BOUNDS. PROCESS */
+ − 1758 /* EACH COMPARTMENT INDIVIDUALLY AND FIND THE MAXIMUM DEPTH ACROSS ALL */
+ − 1759 /* COMPARTMENTS (LEADING COMPARTMENT) */
+ − 1760 /* In this case, we are solving for time - the time when the gas tension in */
+ − 1761 /* the compartment will be equal to ambient pressure. The low bound for time */
+ − 1762 /* is set at zero and the high bound is set at the time it would take to */
+ − 1763 /* ascend to zero ambient pressure (absolute). Since the ascent rate is */
+ − 1764 /* negative, a multiplier of -1.0 is used to make the time positive. The */
+ − 1765 /* desired point when gas tension equals ambient pressure is found at a time */
+ − 1766 /* somewhere between these endpoints. The algorithm checks to make sure that */
+ − 1767 /* the solution lies in between these bounds by first computing the low bound */
+ − 1768 /* and high bound function values. */
+ − 1769 /* =============================================================================== */
+ − 1770
+ − 1771 low_bound = 0.;
+ − 1772 high_bound = starting_ambient_pressure / *rate * -1.0f;
+ − 1773 for (i = 1; i <= 16; ++i)
+ − 1774 {
+ − 1775 initial_helium_pressure = helium_pressure[i - 1];
+ − 1776 initial_nitrogen_pressure = nitrogen_pressure[i - 1];
+ − 1777 function_at_low_bound =
+ − 1778 initial_helium_pressure +
+ − 1779 initial_nitrogen_pressure +
+ − 1780 CONSTANT_PRESSURE_OTHER_GASES -
+ − 1781 starting_ambient_pressure;
+ − 1782 high_bound_helium_pressure =
+ − 1783 schreiner_equation__2(&initial_inspired_he_pressure,
+ − 1784 &helium_rate,
+ − 1785 &high_bound,
+ − 1786 &HELIUM_TIME_CONSTANT[i - 1],
+ − 1787 &initial_helium_pressure);
+ − 1788 high_bound_nitrogen_pressure =
+ − 1789 schreiner_equation__2(&initial_inspired_n2_pressure,
+ − 1790 &nitrogen_rate,
+ − 1791 &high_bound,
+ − 1792 &NITROGEN_TIME_CONSTANT[i - 1],
+ − 1793 &initial_nitrogen_pressure);
+ − 1794 function_at_high_bound = high_bound_helium_pressure +
+ − 1795 high_bound_nitrogen_pressure +
+ − 1796 CONSTANT_PRESSURE_OTHER_GASES;
+ − 1797 if (function_at_high_bound * function_at_low_bound >= 0.0f)
+ − 1798 {
+ − 1799 printf("\nERROR! ROOT IS NOT WITHIN BRACKETS");
+ − 1800 }
+ − 1801
+ − 1802 /* =============================================================================== */
+ − 1803 /* APPLY THE BISECTION METHOD IN SEVERAL ITERATIONS UNTIL A SOLUTION WITH */
+ − 1804 /* THE DESIRED ACCURACY IS FOUND */
+ − 1805 /* Note: the program allows for up to 100 iterations. Normally an exit will */
+ − 1806 /* be made from the loop well before that number. If, for some reason, the */
+ − 1807 /* program exceeds 100 iterations, there will be a pause to alert the user. */
+ − 1808 /* =============================================================================== */
+ − 1809
+ − 1810 if (function_at_low_bound < 0.0f)
+ − 1811 {
+ − 1812 time_to_start_of_deco_zone = low_bound;
+ − 1813 differential_change = high_bound - low_bound;
+ − 1814 } else {
+ − 1815 time_to_start_of_deco_zone = high_bound;
+ − 1816 differential_change = low_bound - high_bound;
+ − 1817 }
+ − 1818 for (j = 1; j <= 100; ++j)
+ − 1819 {
+ − 1820 last_diff_change = differential_change;
+ − 1821 differential_change = last_diff_change * 0.5f;
+ − 1822 mid_range_time =
+ − 1823 time_to_start_of_deco_zone +
+ − 1824 differential_change;
+ − 1825 mid_range_helium_pressure =
+ − 1826 schreiner_equation__2(&initial_inspired_he_pressure,
+ − 1827 &helium_rate,
+ − 1828 &mid_range_time,
+ − 1829 &HELIUM_TIME_CONSTANT[i - 1],
+ − 1830 &initial_helium_pressure);
+ − 1831 mid_range_nitrogen_pressure =
+ − 1832 schreiner_equation__2(&initial_inspired_n2_pressure,
+ − 1833 &nitrogen_rate,
+ − 1834 &mid_range_time,
+ − 1835 &NITROGEN_TIME_CONSTANT[i - 1],
+ − 1836 &initial_nitrogen_pressure);
+ − 1837 function_at_mid_range =
+ − 1838 mid_range_helium_pressure +
+ − 1839 mid_range_nitrogen_pressure +
+ − 1840 CONSTANT_PRESSURE_OTHER_GASES -
+ − 1841 (starting_ambient_pressure + *rate * mid_range_time);
+ − 1842 if (function_at_mid_range <= 0.0f) {
+ − 1843 time_to_start_of_deco_zone = mid_range_time;
+ − 1844 }
+ − 1845 if( fabs(differential_change) < 0.001f
+ − 1846 || function_at_mid_range == 0.0f)
+ − 1847 {
+ − 1848 goto L170;
+ − 1849 }
+ − 1850 /* L150: */
+ − 1851 }
+ − 1852 printf("\nERROR! ROOT SEARCH EXCEEDED MAXIMUM ITERATIONS");
+ − 1853 //pause();
+ − 1854
+ − 1855 /* =============================================================================== */
+ − 1856 /* When a solution with the desired accuracy is found, the program jumps out */
+ − 1857 /* of the loop to Line 170 and assigns the solution value for the individual */
+ − 1858 /* compartment. */
+ − 1859 /* =============================================================================== */
+ − 1860
+ − 1861 L170:
+ − 1862 cpt_depth_start_of_deco_zone =
+ − 1863 starting_ambient_pressure +
+ − 1864 *rate * time_to_start_of_deco_zone -
+ − 1865 barometric_pressure;
+ − 1866
+ − 1867 /* =============================================================================== */
+ − 1868 /* The overall solution will be the compartment with the maximum depth where */
+ − 1869 /* gas tension equals ambient pressure (leading compartment). */
+ − 1870 /* =============================================================================== */
+ − 1871
+ − 1872 *depth_start_of_deco_zone =
+ − 1873 fmaxf(*depth_start_of_deco_zone, cpt_depth_start_of_deco_zone);
+ − 1874 /* L200: */
+ − 1875 }
+ − 1876 return 0;
+ − 1877 } /* calc_start_of_deco_zone */
+ − 1878
+ − 1879 /* =============================================================================== */
+ − 1880 /* SUBROUTINE PROJECTED_ASCENT */
+ − 1881 /* Purpose: This subprogram performs a simulated ascent outside of the main */
+ − 1882 /* program to ensure that a deco ceiling will not be violated due to unusual */
+ − 1883 /* gas loading during ascent (on-gassing). If the deco ceiling is violated, */
+ − 1884 /* the stop depth will be adjusted deeper by the step size until a safe */
+ − 1885 /* ascent can be made. */
+ − 1886 /* =============================================================================== */
+ − 1887
290
+ − 1888 static int projected_ascent(float *starting_depth,
38
+ − 1889 float *rate,
+ − 1890 float *deco_stop_depth,
+ − 1891 float *step_size)
+ − 1892 {
+ − 1893 /* Local variables */
+ − 1894 float weighted_allowable_gradient,
+ − 1895 ending_ambient_pressure,
+ − 1896 temp_gas_loading[16];
+ − 1897 int i;
+ − 1898 float allowable_gas_loading[16];
+ − 1899 float temp_nitrogen_pressure[16];
+ − 1900 float temp_helium_pressure[16];
+ − 1901 float run_time_save = 0;
+ − 1902
+ − 1903 /* loop */
+ − 1904 /* =============================================================================== */
+ − 1905 /* CALCULATIONS */
+ − 1906 /* =============================================================================== */
+ − 1907
+ − 1908
+ − 1909 L665:
+ − 1910 ending_ambient_pressure = *deco_stop_depth + barometric_pressure;
+ − 1911 for (i = 1; i <= 16; ++i) {
+ − 1912 temp_helium_pressure[i - 1] = helium_pressure[i - 1];
+ − 1913 temp_nitrogen_pressure[i - 1] = nitrogen_pressure[i - 1];
+ − 1914 }
+ − 1915 run_time_save = run_time;
+ − 1916 gas_loadings_ascent_descen(temp_helium_pressure, temp_nitrogen_pressure, *starting_depth,*deco_stop_depth,*rate,true);
+ − 1917 run_time = run_time_save;
+ − 1918
+ − 1919 for (i = 1; i <= 16; ++i)
+ − 1920 {
+ − 1921 temp_gas_loading[i - 1] =
+ − 1922 temp_helium_pressure[i - 1] +
+ − 1923 temp_nitrogen_pressure[i - 1];
+ − 1924 if (temp_gas_loading[i - 1] > 0.0f)
+ − 1925 {
+ − 1926 weighted_allowable_gradient =
+ − 1927 (allowable_gradient_he[i - 1] *
+ − 1928 temp_helium_pressure[i - 1] +
+ − 1929 allowable_gradient_n2[i - 1] *
+ − 1930 temp_nitrogen_pressure[i - 1]) / temp_gas_loading[i - 1];
+ − 1931 } else {
+ − 1932 /* Computing MIN */
+ − 1933 weighted_allowable_gradient = fminf(allowable_gradient_he[i - 1],allowable_gradient_n2[i - 1]);
+ − 1934 }
+ − 1935 allowable_gas_loading[i - 1] =
+ − 1936 ending_ambient_pressure +
+ − 1937 weighted_allowable_gradient -
+ − 1938 CONSTANT_PRESSURE_OTHER_GASES;
+ − 1939 /* L670: */
+ − 1940 }
+ − 1941 for (i = 1; i <= 16; ++i) {
+ − 1942 if (temp_gas_loading[i - 1] > allowable_gas_loading[i - 1]) {
+ − 1943 *deco_stop_depth += *step_size;
+ − 1944 goto L665;
+ − 1945 }
+ − 1946 /* L671: */
+ − 1947 }
+ − 1948 return 0;
+ − 1949 } /* projected_ascent */
+ − 1950
+ − 1951 /* =============================================================================== */
+ − 1952 /* SUBROUTINE DECOMPRESSION_STOP */
+ − 1953 /* Purpose: This subprogram calculates the required time at each */
+ − 1954 /* decompression stop. */
+ − 1955 /* =============================================================================== */
+ − 1956
290
+ − 1957 static void decompression_stop(float *deco_stop_depth,
38
+ − 1958 float *step_size,
+ − 1959 _Bool final_deco_calculation)
+ − 1960 {
+ − 1961 /* Local variables */
+ − 1962 float inspired_nitrogen_pressure;
+ − 1963 // short last_segment_number;
+ − 1964 // float weighted_allowable_gradient;
+ − 1965 float initial_helium_pressure[16];
+ − 1966 /* by hw */
51
+ − 1967 float initial_CNS = gCNS_VPM;
38
+ − 1968
+ − 1969 //static float time_counter;
+ − 1970 short i;
+ − 1971 float ambient_pressure;
+ − 1972 float inspired_helium_pressure,
+ − 1973 next_stop;
+ − 1974 //last_run_time,
+ − 1975 //temp_segment_time;
+ − 1976
+ − 1977 float deco_ceiling_depth,
+ − 1978 initial_nitrogen_pressure[16];
+ − 1979 //round_up_operation;
+ − 1980 float fraction_helium_begin;
+ − 1981 float fraction_nitrogen_begin;
+ − 1982 int count = 0;
+ − 1983 _Bool buehlmann_wait = false;
+ − 1984 float tissue_He_saturation[16];
+ − 1985 float tissue_N2_saturation[16];
+ − 1986 float vpm_buehlmann_safety_gradient = 1.0f - (((float)pDiveSettings->vpm_conservatism) / 40);
+ − 1987 /* loop */
+ − 1988 /* =============================================================================== */
+ − 1989 /* CALCULATIONS */
+ − 1990 /* =============================================================================== */
+ − 1991
+ − 1992 segment_time = 0;
+ − 1993 // temp_segment_time = segment_time;
+ − 1994 ambient_pressure = *deco_stop_depth + barometric_pressure;
+ − 1995 //ending_ambient_pressure = ambient_pressure;
+ − 1996 decom_get_inert_gases(ambient_pressure / 10, (&pDiveSettings->decogaslist[mix_number]), &fraction_nitrogen_begin, &fraction_helium_begin );
+ − 1997
+ − 1998 if(*deco_stop_depth == (float)(pDiveSettings->last_stop_depth_bar * 10))
+ − 1999 next_stop = 0;
+ − 2000 else
+ − 2001 {
+ − 2002 next_stop = *deco_stop_depth - *step_size;
+ − 2003 next_stop = fmaxf(next_stop,(float)pDiveSettings->last_stop_depth_bar * 10);
+ − 2004 }
+ − 2005
+ − 2006 inspired_helium_pressure =
+ − 2007 (ambient_pressure - WATER_VAPOR_PRESSURE) * fraction_helium_begin;
+ − 2008 inspired_nitrogen_pressure =
+ − 2009 (ambient_pressure - WATER_VAPOR_PRESSURE) * fraction_nitrogen_begin;
+ − 2010
+ − 2011 /* =============================================================================== */
+ − 2012 /* Check to make sure that program won't lock up if unable to decompress */
+ − 2013 /* to the next stop. If so, write error message and terminate program. */
+ − 2014 /* =============================================================================== */
+ − 2015
+ − 2016 //deco_ceiling_depth = next_stop +1; //deco_ceiling_depth = next_stop + 1;
+ − 2017 if(!vpm_violates_buehlmann)
149
+ − 2018 {
38
+ − 2019 calc_deco_ceiling(&deco_ceiling_depth, false); //weg, weil auf jeden Fall schleife für safety und so konservativer
149
+ − 2020 }
38
+ − 2021 else
149
+ − 2022 {
38
+ − 2023 deco_ceiling_depth = next_stop + 1;
149
+ − 2024 }
38
+ − 2025 if(deco_ceiling_depth > next_stop)
+ − 2026 {
+ − 2027 while (deco_ceiling_depth > next_stop)
+ − 2028 {
+ − 2029
+ − 2030 segment_time += 60;
+ − 2031 if(segment_time >= 999 )
+ − 2032 {
+ − 2033 segment_time = 999 ;
+ − 2034 run_time += segment_time;
+ − 2035 return;
+ − 2036 }
+ − 2037 //goto L700;
+ − 2038 initial_CNS = gCNS_VPM;
+ − 2039 decom_oxygen_calculate_cns_exposure(60*60,&pDiveSettings->decogaslist[mix_number],ambient_pressure/10,&gCNS_VPM);
+ − 2040 for (i = 0; i < 16; i++)
+ − 2041 {
+ − 2042 initial_helium_pressure[i] = helium_pressure[i];
+ − 2043 initial_nitrogen_pressure[i] = nitrogen_pressure[i];
+ − 2044 helium_pressure[i] += (inspired_helium_pressure - helium_pressure[i]) * float_buehlmann_He_factor_expositon_one_hour[i];
+ − 2045 nitrogen_pressure[i] += (inspired_nitrogen_pressure - nitrogen_pressure[i]) * float_buehlmann_N2_factor_expositon_one_hour[i];
+ − 2046 }
+ − 2047 calc_deco_ceiling(&deco_ceiling_depth, false);
+ − 2048 }
+ − 2049 if(deco_ceiling_depth < next_stop)
+ − 2050 {
+ − 2051 segment_time -= 60;
+ − 2052 gCNS_VPM = initial_CNS;
+ − 2053 for (i = 0; i < 16; i++)
+ − 2054 {
+ − 2055 helium_pressure[i] = initial_helium_pressure[i];
+ − 2056 nitrogen_pressure[i] = initial_nitrogen_pressure[i];
+ − 2057 }
+ − 2058 deco_ceiling_depth = next_stop +1;
+ − 2059 }
+ − 2060 count = 0;
+ − 2061 while (deco_ceiling_depth > next_stop && count < 13)
+ − 2062 {
+ − 2063 count++;
+ − 2064 segment_time += 5;
+ − 2065 //goto L700;
+ − 2066 initial_CNS = gCNS_VPM;
+ − 2067 decom_oxygen_calculate_cns_exposure(60*5,&pDiveSettings->decogaslist[mix_number],ambient_pressure/10,&gCNS_VPM);
+ − 2068 for (i = 0; i < 16; i++)
+ − 2069 {
+ − 2070 initial_helium_pressure[i] = helium_pressure[i];
+ − 2071 initial_nitrogen_pressure[i] = nitrogen_pressure[i];
+ − 2072 helium_pressure[i] += (inspired_helium_pressure - helium_pressure[i]) * float_buehlmann_He_factor_expositon_five_minutes[i];
+ − 2073 nitrogen_pressure[i] += (inspired_nitrogen_pressure - nitrogen_pressure[i]) * float_buehlmann_N2_factor_expositon_five_minutes[i];
+ − 2074 }
+ − 2075 calc_deco_ceiling(&deco_ceiling_depth, false);
+ − 2076 }
+ − 2077 if(deco_ceiling_depth < next_stop)
+ − 2078 {
+ − 2079 segment_time -= 5;
+ − 2080 gCNS_VPM = initial_CNS;
+ − 2081 for (i = 0; i < 16; i++) {
+ − 2082 helium_pressure[i] = initial_helium_pressure[i];
+ − 2083 nitrogen_pressure[i] = initial_nitrogen_pressure[i];
+ − 2084 }
+ − 2085 deco_ceiling_depth = next_stop +1;
+ − 2086 }
+ − 2087 buehlmann_wait = false;
+ − 2088 while (buehlmann_wait || (deco_ceiling_depth > next_stop))
+ − 2089 {
+ − 2090 //time_counter = temp_segment_time;
+ − 2091 segment_time += 1;
+ − 2092
+ − 2093 if(segment_time >= 999 )
+ − 2094 {
+ − 2095 segment_time = 999 ;
+ − 2096 run_time += segment_time;
+ − 2097 return;
+ − 2098 }
+ − 2099 //goto L700;
+ − 2100 initial_CNS = gCNS_VPM;
+ − 2101 decom_oxygen_calculate_cns_exposure(60*1,&pDiveSettings->decogaslist[mix_number],ambient_pressure/10,&gCNS_VPM);
+ − 2102 for (i = 0; i < 16; i++)
+ − 2103 {
+ − 2104 initial_helium_pressure[i] = helium_pressure[i];
+ − 2105 initial_nitrogen_pressure[i] = nitrogen_pressure[i];
+ − 2106 helium_pressure[i] += (inspired_helium_pressure - helium_pressure[i]) * float_buehlmann_He_factor_expositon_one_minute[i];
+ − 2107 nitrogen_pressure[i] += (inspired_nitrogen_pressure - nitrogen_pressure[i]) * float_buehlmann_N2_factor_expositon_one_minute[i];
+ − 2108 }
+ − 2109 if(!buehlmann_wait)
+ − 2110 calc_deco_ceiling(&deco_ceiling_depth, false);
+ − 2111
+ − 2112 if(buehlmannSafety && final_deco_calculation && !(deco_ceiling_depth > next_stop))
+ − 2113 {
+ − 2114 for (i = 0; i < 16; i++)
+ − 2115 {
+ − 2116 tissue_He_saturation[i] = helium_pressure[i] / 10;
+ − 2117 tissue_N2_saturation[i] = nitrogen_pressure[i] / 10;
+ − 2118 }
+ − 2119 if( (fabsf(nitrogen_pressure[15] - inspired_nitrogen_pressure) < 0.00001f) && (fabsf(helium_pressure[15] - inspired_helium_pressure) < 0.00001f)
+ − 2120 && (fabsf(nitrogen_pressure[0] - inspired_nitrogen_pressure) < 0.00001f) && (fabsf(helium_pressure[0] - inspired_helium_pressure) < 0.00001f))
+ − 2121 {
+ − 2122 buehlmann_wait_exceeded = true;
+ − 2123 break;
+ − 2124 }
+ − 2125
+ − 2126 if(decom_tissue_test_tolerance(tissue_N2_saturation, tissue_He_saturation, vpm_buehlmann_safety_gradient, (next_stop / 10.0f) + pInput->pressure_surface_bar))
+ − 2127 break;
+ − 2128
+ − 2129 buehlmann_wait = true;
+ − 2130 }
+ − 2131 }
+ − 2132 if(buehlmann_wait)
149
+ − 2133 {
38
+ − 2134 vpm_violates_buehlmann = true;
149
+ − 2135 }
+ − 2136 if(!buehlmann_wait)
38
+ − 2137 {
+ − 2138 if(deco_ceiling_depth < next_stop)
+ − 2139 {
+ − 2140 segment_time -= 1;
+ − 2141 gCNS_VPM = initial_CNS;
+ − 2142 for (i = 0; i < 16; i++) {
+ − 2143 helium_pressure[i] = initial_helium_pressure[i];
+ − 2144 nitrogen_pressure[i] = initial_nitrogen_pressure[i];
+ − 2145 }
+ − 2146 deco_ceiling_depth = next_stop +1;
+ − 2147 }
+ − 2148 while (deco_ceiling_depth > next_stop)
+ − 2149 {
+ − 2150 //time_counter = temp_segment_time;
+ − 2151 segment_time += (float) 1.0f / 3.0f;
+ − 2152 //goto L700;
+ − 2153 initial_CNS = gCNS_VPM;
+ − 2154 decom_oxygen_calculate_cns_exposure(20,&pDiveSettings->decogaslist[mix_number],ambient_pressure/10,&gCNS_VPM);
+ − 2155 for (i = 0; i < 16; i++)
+ − 2156 {
+ − 2157 helium_pressure[i] += (inspired_helium_pressure - helium_pressure[i]) * float_buehlmann_He_factor_expositon_20_seconds[i];
+ − 2158 nitrogen_pressure[i] += (inspired_nitrogen_pressure - nitrogen_pressure[i]) * float_buehlmann_N2_factor_expositon_20_seconds[i];
+ − 2159 }
+ − 2160 calc_deco_ceiling(&deco_ceiling_depth, false);
+ − 2161 }
+ − 2162 }
+ − 2163 }
+ − 2164
+ − 2165 /*float pressure_save =dive_data.pressure;
+ − 2166 dive_data.pressure = ambient_pressure/10;
+ − 2167 tissues_exposure_stage(st_deco_test,(int)(segment_time * 60), &dive_data, &gaslist);
+ − 2168 dive_data.pressure = pressure_save;*/
+ − 2169 run_time += segment_time;
+ − 2170 return;
+ − 2171 } /* decompression_stop */
+ − 2172
+ − 2173 /* =============================================================================== */
+ − 2174 // SUROUTINE BOYLES_LAW_COMPENSATION
+ − 2175 // Purpose: This subprogram calculates the reduction in allowable gradients
+ − 2176 // with decreasing ambient pressure during the decompression profile based
+ − 2177 // on Boyle's Law considerations.
+ − 2178 //===============================================================================
290
+ − 2179 static void BOYLES_LAW_COMPENSATION (float* First_Stop_Depth,
38
+ − 2180 float* Deco_Stop_Depth,
+ − 2181 float* Step_Size)
+ − 2182 {
+ − 2183 short i;
+ − 2184
+ − 2185 float Next_Stop;
+ − 2186 float Ambient_Pressure_First_Stop, Ambient_Pressure_Next_Stop;
+ − 2187 float Amb_Press_First_Stop_Pascals, Amb_Press_Next_Stop_Pascals;
+ − 2188 float A, B, C, Low_Bound, High_Bound, Ending_Radius;
+ − 2189 float Deco_Gradient_Pascals;
+ − 2190 float Allow_Grad_First_Stop_He_Pa, Radius_First_Stop_He;
+ − 2191 float Allow_Grad_First_Stop_N2_Pa, Radius_First_Stop_N2;
+ − 2192
+ − 2193 //===============================================================================
+ − 2194 // LO//AL ARRAYS
+ − 2195 //===============================================================================
+ − 2196 // float Radius1_He[16], Radius2_He[16];
+ − 2197 // float Radius1_N2[16], Radius2_N2[16];
+ − 2198 float root_factor;
+ − 2199
+ − 2200 //===============================================================================
+ − 2201 // CALCULATIONS
+ − 2202 //===============================================================================
+ − 2203 Next_Stop = *Deco_Stop_Depth - *Step_Size;
+ − 2204
+ − 2205 Ambient_Pressure_First_Stop = *First_Stop_Depth +
+ − 2206 barometric_pressure;
+ − 2207
+ − 2208 Ambient_Pressure_Next_Stop = Next_Stop + barometric_pressure;
+ − 2209
+ − 2210 Amb_Press_First_Stop_Pascals = (Ambient_Pressure_First_Stop/UNITS_FACTOR) * 101325.0f;
+ − 2211
+ − 2212 Amb_Press_Next_Stop_Pascals =
+ − 2213 (Ambient_Pressure_Next_Stop/UNITS_FACTOR) * 101325.0f;
+ − 2214 root_factor = powf(Amb_Press_First_Stop_Pascals/Amb_Press_Next_Stop_Pascals,1.0f / 3.0f);
+ − 2215
+ − 2216 for( i = 0; i < 16;i++)
+ − 2217 {
+ − 2218 Allow_Grad_First_Stop_He_Pa =
+ − 2219 (allowable_gradient_he[i]/UNITS_FACTOR) * 101325.0f;
+ − 2220
+ − 2221 Radius_First_Stop_He = (2.0f * SURFACE_TENSION_GAMMA) /
+ − 2222 Allow_Grad_First_Stop_He_Pa;
+ − 2223
+ − 2224 // Radius1_He[i] = Radius_First_Stop_He;
+ − 2225 A = Amb_Press_Next_Stop_Pascals;
+ − 2226 B = -2.0f * SURFACE_TENSION_GAMMA;
+ − 2227 C = (Amb_Press_First_Stop_Pascals + (2.0f * SURFACE_TENSION_GAMMA)/
+ − 2228 Radius_First_Stop_He)* Radius_First_Stop_He*
+ − 2229 (Radius_First_Stop_He*(Radius_First_Stop_He));
+ − 2230 Low_Bound = Radius_First_Stop_He;
+ − 2231 High_Bound = Radius_First_Stop_He * root_factor;
+ − 2232 //*pow(Amb_Press_First_Stop_Pascals/Amb_Press_Next_Stop_Pascals,1.0/3.0);
+ − 2233 //*(Amb_Press_First_Stop_Pascals/Amb_Press_Next_Stop_Pascals)**(1.0/3.0);
+ − 2234
+ − 2235 radius_root_finder(&A,&B,&C, &Low_Bound, &High_Bound,
+ − 2236 &Ending_Radius);
+ − 2237
+ − 2238 // Radius2_He[i] = Ending_Radius;
+ − 2239 Deco_Gradient_Pascals = (2.0f * SURFACE_TENSION_GAMMA) /
+ − 2240 Ending_Radius;
+ − 2241
+ − 2242 deco_gradient_he[i] = (Deco_Gradient_Pascals / 101325.0f)*
+ − 2243 UNITS_FACTOR;
+ − 2244
+ − 2245 }
+ − 2246
+ − 2247 for( i = 0; i < 16;i++)
+ − 2248 {
+ − 2249 Allow_Grad_First_Stop_N2_Pa =
+ − 2250 (allowable_gradient_n2[i]/UNITS_FACTOR) * 101325.0f;
+ − 2251
+ − 2252 Radius_First_Stop_N2 = (2.0f * SURFACE_TENSION_GAMMA) /
+ − 2253 Allow_Grad_First_Stop_N2_Pa;
+ − 2254
+ − 2255 // Radius1_N2[i] = Radius_First_Stop_N2;
+ − 2256 A = Amb_Press_Next_Stop_Pascals;
+ − 2257 B = -2.0f * SURFACE_TENSION_GAMMA;
+ − 2258 C = (Amb_Press_First_Stop_Pascals + (2.0f * SURFACE_TENSION_GAMMA)/
+ − 2259 Radius_First_Stop_N2)* Radius_First_Stop_N2*
+ − 2260 (Radius_First_Stop_N2*(Radius_First_Stop_N2));
+ − 2261 Low_Bound = Radius_First_Stop_N2;
+ − 2262 High_Bound = Radius_First_Stop_N2* root_factor;//pow(Amb_Press_First_Stop_Pascals/Amb_Press_Next_Stop_Pascals,1.0/3.0);
+ − 2263
+ − 2264 //High_Bound = Radius_First_Stop_N2*exp(log(Amb_Press_First_Stop_Pascals/Amb_Press_Next_Stop_Pascals)/3);
+ − 2265 radius_root_finder(&A,&B,&C, &Low_Bound, &High_Bound,
+ − 2266 &Ending_Radius);
+ − 2267
+ − 2268 // Radius2_N2[i] = Ending_Radius;
+ − 2269 Deco_Gradient_Pascals = (2.0f * SURFACE_TENSION_GAMMA) /
+ − 2270 Ending_Radius;
+ − 2271
+ − 2272 deco_gradient_n2[i] = (Deco_Gradient_Pascals / 101325.0f)*
+ − 2273 UNITS_FACTOR;
+ − 2274 }
+ − 2275 }
+ − 2276
+ − 2277 /* =============================================================================== */
292
+ − 2278 // vpm_calc_ndl
+ − 2279 // Purpose: This function computes NDL (time where no decostops are needed)
38
+ − 2280 //===============================================================================
291
+ − 2281 #define MAX_NDL 240
+ − 2282
292
+ − 2283 static int vpm_calc_ndl(void)
38
+ − 2284 {
+ − 2285 static float future_helium_pressure[16];
+ − 2286 static float future_nitrogen_pressure[16];
+ − 2287 static int temp_segment_time;
+ − 2288 static int mix_number;
+ − 2289 static float inspired_helium_pressure;
+ − 2290 static float inspired_nitrogen_pressure;
+ − 2291
+ − 2292 float previous_helium_pressure[16];
+ − 2293 float previous_nitrogen_pressure[16];
+ − 2294 float ambient_pressure;
+ − 2295 float fraction_helium_begin;
+ − 2296 float fraction_nitrogen_begin;
+ − 2297 int i = 0;
+ − 2298 int count = 0;
+ − 2299 int status = CALC_END;
291
+ − 2300
38
+ − 2301 for(i = 0; i < 16;i++)
+ − 2302 {
+ − 2303 future_helium_pressure[i] = pInput->tissue_helium_bar[i] * 10;//tissue_He_saturation[st_dive][i] * 10;
+ − 2304 future_nitrogen_pressure[i] = pInput->tissue_nitrogen_bar[i] * 10;
+ − 2305 }
+ − 2306 temp_segment_time = 0;
+ − 2307
+ − 2308 mix_number = 0;
+ − 2309 ambient_pressure = pInput->pressure_ambient_bar * 10;
+ − 2310 decom_get_inert_gases( ambient_pressure / 10, (&pDiveSettings->decogaslist[mix_number]) , &fraction_nitrogen_begin, &fraction_helium_begin );
+ − 2311 inspired_helium_pressure =(ambient_pressure - WATER_VAPOR_PRESSURE) * fraction_helium_begin;
+ − 2312 inspired_nitrogen_pressure =(ambient_pressure - WATER_VAPOR_PRESSURE) *fraction_nitrogen_begin;
+ − 2313
+ − 2314 status = CALC_END;
+ − 2315 while (status == CALC_END)
+ − 2316 {
+ − 2317 count++;
+ − 2318 temp_segment_time += 60;
291
+ − 2319 if(temp_segment_time >= MAX_NDL)
38
+ − 2320 {
+ − 2321 pDecoInfo->output_ndl_seconds = temp_segment_time * 60;
292
+ − 2322 return CALC_NDL;
38
+ − 2323 }
+ − 2324 run_time += 60;
+ − 2325 //goto L700;
+ − 2326 for (i = 1; i <= 16; ++i) {
+ − 2327 previous_helium_pressure[i-1] = future_helium_pressure[i - 1];
+ − 2328 previous_nitrogen_pressure[i - 1] = future_nitrogen_pressure[i - 1];
+ − 2329 future_helium_pressure[i - 1] = future_helium_pressure[i - 1] + (inspired_helium_pressure - future_helium_pressure[i - 1]) * float_buehlmann_He_factor_expositon_one_hour[i-1];
+ − 2330 future_nitrogen_pressure[i - 1] = future_nitrogen_pressure[i - 1] + (inspired_nitrogen_pressure - future_nitrogen_pressure[i - 1]) * float_buehlmann_N2_factor_expositon_one_hour[i-1];
+ − 2331 helium_pressure[i - 1] = future_helium_pressure[i - 1];
+ − 2332 nitrogen_pressure[i - 1] = future_nitrogen_pressure[i - 1];
+ − 2333 }
+ − 2334 vpm_calc_deco();
+ − 2335 while((status = vpm_calc_critcal_volume(true,true)) == CALC_CRITICAL);
+ − 2336
+ − 2337 }
+ − 2338
+ − 2339 temp_segment_time -= 60;
+ − 2340 run_time -= 60;
+ − 2341 for (i = 1; i <= 16; ++i)
+ − 2342 {
+ − 2343 future_helium_pressure[i - 1] = previous_helium_pressure[i-1];
+ − 2344 future_nitrogen_pressure[i - 1] = previous_nitrogen_pressure[i - 1];
+ − 2345 }
+ − 2346
+ − 2347 status = CALC_END;
+ − 2348 if(temp_segment_time < 60)
+ − 2349 nullzeit_unter60 = true;
+ − 2350
+ − 2351 while (status == CALC_END)
+ − 2352 {
+ − 2353 temp_segment_time += 5;
291
+ − 2354 if(temp_segment_time >= MAX_NDL)
38
+ − 2355 {
+ − 2356 pDecoInfo->output_ndl_seconds = temp_segment_time * 60;
292
+ − 2357 return CALC_NDL;
38
+ − 2358 }
+ − 2359 if(nullzeit_unter60 && temp_segment_time > 60)
+ − 2360 {
+ − 2361 nullzeit_unter60 = false;
292
+ − 2362 return CALC_NDL;
38
+ − 2363 }
+ − 2364 run_time += 5;
+ − 2365 //goto L700;
+ − 2366 for (i = 1; i <= 16; ++i) {
+ − 2367 previous_helium_pressure[i-1] = future_helium_pressure[i - 1];
+ − 2368 previous_nitrogen_pressure[i - 1] = future_nitrogen_pressure[i - 1];
+ − 2369 future_helium_pressure[i - 1] = future_helium_pressure[i - 1] + (inspired_helium_pressure - future_helium_pressure[i - 1]) * float_buehlmann_He_factor_expositon_five_minutes[i-1];
+ − 2370 future_nitrogen_pressure[i - 1] = future_nitrogen_pressure[i - 1] + (inspired_nitrogen_pressure - future_nitrogen_pressure[i - 1]) * float_buehlmann_N2_factor_expositon_five_minutes[i-1];
+ − 2371 helium_pressure[i - 1] = future_helium_pressure[i - 1];
+ − 2372 nitrogen_pressure[i - 1] = future_nitrogen_pressure[i - 1];
+ − 2373 }
+ − 2374 vpm_calc_deco();
+ − 2375 while((status =vpm_calc_critcal_volume(true,true)) == CALC_CRITICAL);
+ − 2376 }
+ − 2377 temp_segment_time -= 5;
+ − 2378 run_time -= 5;
+ − 2379 for (i = 1; i <= 16; ++i) {
+ − 2380 future_helium_pressure[i - 1] = previous_helium_pressure[i-1];
+ − 2381 future_nitrogen_pressure[i - 1] = previous_nitrogen_pressure[i - 1];
+ − 2382 }
+ − 2383 status = CALC_END;
291
+ − 2384
38
+ − 2385 if(temp_segment_time <= 20)
+ − 2386 {
+ − 2387 while (status == CALC_END)
+ − 2388 {
+ − 2389 temp_segment_time += minimum_deco_stop_time;
+ − 2390 run_time += minimum_deco_stop_time;
+ − 2391 //goto L700;
+ − 2392 for (i = 1; i <= 16; ++i) {
+ − 2393 future_helium_pressure[i - 1] = future_helium_pressure[i - 1] + (inspired_helium_pressure - future_helium_pressure[i - 1]) * float_buehlmann_He_factor_expositon_one_minute[i-1];
+ − 2394 future_nitrogen_pressure[i - 1] = future_nitrogen_pressure[i - 1] + (inspired_nitrogen_pressure - future_nitrogen_pressure[i - 1]) * float_buehlmann_N2_factor_expositon_one_minute[i-1];
+ − 2395 helium_pressure[i - 1] = future_helium_pressure[i - 1];
+ − 2396 nitrogen_pressure[i - 1] =future_nitrogen_pressure[i - 1];
+ − 2397
+ − 2398 }
+ − 2399 vpm_calc_deco();
+ − 2400 while((status =vpm_calc_critcal_volume(true,true)) == CALC_CRITICAL);
+ − 2401
+ − 2402 }
+ − 2403 }
+ − 2404 else
+ − 2405 temp_segment_time += 5;
+ − 2406 pDecoInfo->output_ndl_seconds = temp_segment_time * 60;
+ − 2407 if(temp_segment_time > 1)
292
+ − 2408 return CALC_NDL;
38
+ − 2409 else
+ − 2410 return CALC_BEGIN;
+ − 2411 }