1 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
3 Module: FGTurboProp.cpp
4 Author: Jiri "Javky" Javurek
5 based on SimTurbine and Turbine engine from David Culp
6 Date started: 05/14/2004
7 Purpose: This module models a turbo propeller engine.
9 ------------- Copyright (C) 2004 (javky@email.cz) ---------
11 This program is free software; you can redistribute it and/or modify it under
12 the terms of the GNU Lesser General Public License as published by the Free Software
13 Foundation; either version 2 of the License, or (at your option) any later
16 This program is distributed in the hope that it will be useful, but WITHOUT
17 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
18 FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
21 You should have received a copy of the GNU Lesser General Public License along with
22 this program; if not, write to the Free Software Foundation, Inc., 59 Temple
23 Place - Suite 330, Boston, MA 02111-1307, USA.
25 Further information about the GNU Lesser General Public License can also be found on
26 the world wide web at http://www.gnu.org.
28 FUNCTIONAL DESCRIPTION
29 --------------------------------------------------------------------------------
31 This class descends from the FGEngine class and models a Turbo propeller engine
32 based on parameters given in the engine config file for this class
35 --------------------------------------------------------------------------------
40 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
42 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
46 #include "FGTurboProp.h"
48 #include "FGPropeller.h"
50 #include "models/FGAuxiliary.h"
56 static const char *IdSrc = "$Id$";
57 static const char *IdHdr = ID_TURBOPROP;
59 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
61 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
63 FGTurboProp::FGTurboProp(FGFDMExec* exec, Element *el, int engine_number)
64 : FGEngine(exec, el, engine_number),
65 ITT_N1(NULL), EnginePowerRPM_N1(NULL), EnginePowerVC(NULL)
73 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
75 FGTurboProp::~FGTurboProp()
78 delete EnginePowerRPM_N1;
83 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
85 bool FGTurboProp::Load(FGFDMExec* exec, Element *el)
88 MaxStartingTime = 999999; //very big timeout -> infinite
91 // ToDo: Need to make sure units are properly accounted for below.
93 if (el->FindElement("milthrust"))
94 MilThrust = el->FindElementValueAsNumberConvertTo("milthrust","LBS");
95 if (el->FindElement("idlen1"))
96 IdleN1 = el->FindElementValueAsNumber("idlen1");
97 if (el->FindElement("idlen2"))
98 IdleN2 = el->FindElementValueAsNumber("idlen2");
99 if (el->FindElement("maxn1"))
100 MaxN1 = el->FindElementValueAsNumber("maxn1");
101 if (el->FindElement("maxn2"))
102 MaxN2 = el->FindElementValueAsNumber("maxn2");
103 if (el->FindElement("betarangeend"))
104 BetaRangeThrottleEnd = el->FindElementValueAsNumber("betarangeend")/100.0;
105 if (el->FindElement("reversemaxpower"))
106 ReverseMaxPower = el->FindElementValueAsNumber("reversemaxpower")/100.0;
108 if (el->FindElement("maxpower"))
109 MaxPower = el->FindElementValueAsNumber("maxpower");
110 if (el->FindElement("idlefuelflow"))
111 IdleFF = el->FindElementValueAsNumber("idlefuelflow");
112 if (el->FindElement("psfc"))
113 PSFC = el->FindElementValueAsNumber("psfc");
114 if (el->FindElement("n1idle_max_delay"))
115 Idle_Max_Delay = el->FindElementValueAsNumber("n1idle_max_delay");
116 if (el->FindElement("maxstartingtime"))
117 MaxStartingTime = el->FindElementValueAsNumber("maxstartingtime");
118 if (el->FindElement("startern1"))
119 StarterN1 = el->FindElementValueAsNumber("startern1");
120 if (el->FindElement("ielumaxtorque"))
121 Ielu_max_torque = el->FindElementValueAsNumber("ielumaxtorque");
122 if (el->FindElement("itt_delay"))
123 ITT_Delay = el->FindElementValueAsNumber("itt_delay");
125 Element *table_element;
127 FGPropertyManager* PropertyManager = exec->GetPropertyManager();
130 table_element = el->FindNextElement("table");
131 if (!table_element) break;
132 name = table_element->GetAttributeValue("name");
133 if (name == "EnginePowerVC") {
134 EnginePowerVC = new FGTable(PropertyManager, table_element);
135 } else if (name == "EnginePowerRPM_N1") {
136 EnginePowerRPM_N1 = new FGTable(PropertyManager, table_element);
137 } else if (name == "ITT_N1") {
138 ITT_N1 = new FGTable(PropertyManager, table_element);
140 cerr << "Unknown table type: " << name << " in turbine definition." <<
145 // Pre-calculations and initializations
148 N1_factor = MaxN1 - IdleN1;
149 N2_factor = MaxN2 - IdleN2;
150 OilTemp_degK = (Auxiliary->GetTotalTemperature() - 491.69) * 0.5555556 + 273.0;
151 if (IdleFF==-1) IdleFF = pow(MilThrust, 0.2) * 107.0; // just an estimate
153 cout << "ENG POWER:" << EnginePowerRPM_N1->GetValue(1200,90) << "\n";
158 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
159 // The main purpose of Calculate() is to determine what phase the engine should
160 // be in, then call the corresponding function.
162 double FGTurboProp::Calculate(void)
164 TAT = (Auxiliary->GetTotalTemperature() - 491.69) * 0.5555556;
165 dt = State->Getdt() * Propulsion->GetRate();
167 ThrottleCmd = FCS->GetThrottleCmd(EngineNumber);
169 Prop_RPM = Thruster->GetRPM() * Thruster->GetGearRatio();
170 if (Thruster->GetType() == FGThruster::ttPropeller) {
171 ((FGPropeller*)Thruster)->SetAdvance(FCS->GetPropAdvance(EngineNumber));
172 ((FGPropeller*)Thruster)->SetFeather(FCS->GetPropFeather(EngineNumber));
173 ((FGPropeller*)Thruster)->SetReverse(Reversed);
175 ((FGPropeller*)Thruster)->SetReverseCoef(ThrottleCmd);
177 ((FGPropeller*)Thruster)->SetReverseCoef(0.0);
182 if (ThrottleCmd < BetaRangeThrottleEnd) {
183 ThrottleCmd = 0.0; // idle when in Beta-range
186 ThrottleCmd = (ThrottleCmd-BetaRangeThrottleEnd)/(1-BetaRangeThrottleEnd) * ReverseMaxPower;
190 // When trimming is finished check if user wants engine OFF or RUNNING
191 if ((phase == tpTrim) && (dt > 0)) {
192 if (Running && !Starved) {
196 OilTemp_degK = 366.0;
202 Eng_Temperature = TAT;
203 OilTemp_degK = TAT+273.15;
207 if (!Running && Starter) {
208 if (phase == tpOff) {
210 if (StartTime < 0) StartTime=0;
213 if (!Running && !Cutoff && (N1 > 15.0)) {
217 if (Cutoff && (phase != tpSpinUp)) phase = tpOff;
218 if (dt == 0) phase = tpTrim;
219 if (Starved) phase = tpOff;
220 if (Condition >= 10) {
226 if (Ielu_max_torque > 0
227 && -Ielu_max_torque > ((FGPropeller*)(Thruster))->GetTorque()
228 && ThrottleCmd >= OldThrottle ) {
229 ThrottleCmd = OldThrottle - 0.1 * dt; //IELU down
230 Ielu_intervent = true;
231 } else if (Ielu_max_torque > 0 && Ielu_intervent && ThrottleCmd >= OldThrottle) {
232 ThrottleCmd = OldThrottle;
233 ThrottleCmd = OldThrottle + 0.05 * dt; //IELU up
234 Ielu_intervent = true;
236 Ielu_intervent = false;
239 Ielu_intervent = false;
241 OldThrottle = ThrottleCmd;
244 case tpOff: Eng_HP = Off(); break;
245 case tpRun: Eng_HP = Run(); break;
246 case tpSpinUp: Eng_HP = SpinUp(); break;
247 case tpStart: Eng_HP = Start(); break;
251 //printf ("EngHP: %lf / Requi: %lf\n",Eng_HP,Prop_Required_Power);
252 PowerAvailable = (Eng_HP * hptoftlbssec) - Thruster->GetPowerRequired();
254 return Thruster->Calculate(PowerAvailable);
258 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
260 double FGTurboProp::Off(void)
262 double qbar = Auxiliary->Getqbar();
263 Running = false; EngStarting = false;
265 FuelFlow_pph = Seek(&FuelFlow_pph, 0, 800.0, 800.0);
267 //allow the air turn with generator
268 N1 = ExpSeek(&N1, qbar/15.0, Idle_Max_Delay*2.5, Idle_Max_Delay * 5);
270 OilTemp_degK = ExpSeek(&OilTemp_degK,273.15 + TAT, 400 , 400);
272 Eng_Temperature = ExpSeek(&Eng_Temperature,TAT,300,400);
273 double ITT_goal = ITT_N1->GetValue(N1,0.1) + ((N1>20) ? 0.0 : (20-N1)/20.0 * Eng_Temperature);
274 Eng_ITT_degC = ExpSeek(&Eng_ITT_degC,ITT_goal,ITT_Delay,ITT_Delay*1.2);
276 OilPressure_psi = (N1/100.0*0.25+(0.1-(OilTemp_degK-273.15)*0.1/80.0)*N1/100.0) / 7692.0e-6; //from MPa to psi
278 ConsumeFuel(); // for possible setting Starved = false when fuel tank
279 // is refilled (fuel crossfeed etc.)
281 if (Prop_RPM>5) return -0.012; // friction in engine when propeller spining (estimate)
285 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
287 double FGTurboProp::Run(void)
289 double thrust = 0.0, EngPower_HP, eff_coef;
290 Running = true; Starter = false; EngStarting = false;
294 N1 = ExpSeek(&N1, IdleN1 + ThrottleCmd * N1_factor, Idle_Max_Delay, Idle_Max_Delay * 2.4);
296 EngPower_HP = EnginePowerRPM_N1->GetValue(Prop_RPM,N1);
297 EngPower_HP *= EnginePowerVC->GetValue();
298 if (EngPower_HP > MaxPower) EngPower_HP = MaxPower;
300 eff_coef = 9.333 - (N1)/12; // 430%Fuel at 60%N1
301 FuelFlow_pph = PSFC * EngPower_HP * eff_coef;
303 Eng_Temperature = ExpSeek(&Eng_Temperature,Eng_ITT_degC,300,400);
304 double ITT_goal = ITT_N1->GetValue((N1-old_N1)*300+N1,1);
305 Eng_ITT_degC = ExpSeek(&Eng_ITT_degC,ITT_goal,ITT_Delay,ITT_Delay*1.2);
307 OilPressure_psi = (N1/100.0*0.25+(0.1-(OilTemp_degK-273.15)*0.1/80.0)*N1/100.0) / 7692.0e-6; //from MPa to psi
309 EPR = 1.0 + thrust/MilThrust;
311 OilTemp_degK = Seek(&OilTemp_degK, 353.15, 0.4-N1*0.001, 0.04);
315 if (Cutoff) phase = tpOff;
316 if (Starved) phase = tpOff;
321 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
323 double FGTurboProp::SpinUp(void)
326 Running = false; EngStarting = true;
329 if (!GeneratorPower) {
336 N1 = ExpSeek(&N1, StarterN1, Idle_Max_Delay * 6, Idle_Max_Delay * 2.4);
338 Eng_Temperature = ExpSeek(&Eng_Temperature,TAT,300,400);
339 double ITT_goal = ITT_N1->GetValue(N1,0.1) + ((N1>20) ? 0.0 : (20-N1)/20.0 * Eng_Temperature);
340 Eng_ITT_degC = ExpSeek(&Eng_ITT_degC,ITT_goal,ITT_Delay,ITT_Delay*1.2);
342 OilTemp_degK = ExpSeek(&OilTemp_degK,273.15 + TAT, 400 , 400);
344 OilPressure_psi = (N1/100.0*0.25+(0.1-(OilTemp_degK-273.15)*0.1/80.0)*N1/100.0) / 7692.0e-6; //from MPa to psi
345 NozzlePosition = 1.0;
347 EngPower_HP = EnginePowerRPM_N1->GetValue(Prop_RPM,N1);
348 EngPower_HP *= EnginePowerVC->GetValue();
349 if (EngPower_HP > MaxPower) EngPower_HP = MaxPower;
351 if (StartTime>=0) StartTime+=dt;
352 if (StartTime > MaxStartingTime && MaxStartingTime > 0) { //start failed due timeout
357 ConsumeFuel(); // for possible setting Starved = false when fuel tank
358 // is refilled (fuel crossfeed etc.)
363 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
365 double FGTurboProp::Start(void)
367 double EngPower_HP,eff_coef;
369 if ((N1 > 15.0) && !Starved) { // minimum 15% N2 needed for start
371 Cranking = true; // provided for sound effects signal
373 EngPower_HP = EnginePowerRPM_N1->GetValue(Prop_RPM,N1);
374 EngPower_HP *= EnginePowerVC->GetValue();
375 if (EngPower_HP > MaxPower) EngPower_HP = MaxPower;
376 N1 = ExpSeek(&N1, IdleN1*1.1, Idle_Max_Delay*4, Idle_Max_Delay * 2.4);
377 eff_coef = 9.333 - (N1)/12; // 430%Fuel at 60%N1
378 FuelFlow_pph = PSFC * EngPower_HP * eff_coef;
379 Eng_Temperature = ExpSeek(&Eng_Temperature,Eng_ITT_degC,300,400);
380 double ITT_goal = ITT_N1->GetValue((N1-old_N1)*300+N1,1);
381 Eng_ITT_degC = ExpSeek(&Eng_ITT_degC,ITT_goal,ITT_Delay,ITT_Delay*1.2);
383 OilPressure_psi = (N1/100.0*0.25+(0.1-(OilTemp_degK-273.15)*0.1/80.0)*N1/100.0) / 7692.0e-6; //from MPa to psi
384 OilTemp_degK = Seek(&OilTemp_degK, 353.15, 0.4-N1*0.001, 0.04);
394 } else { // no start if N2 < 15% or Starved
405 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
407 double FGTurboProp::CalcFuelNeed(void)
409 double dT = State->Getdt() * Propulsion->GetRate();
410 FuelFlowRate = FuelFlow_pph / 3600.0;
411 FuelExpended = FuelFlowRate * dT;
415 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
417 double FGTurboProp::Seek(double *var, double target, double accel, double decel)
422 if (v < target) v = target;
423 } else if (v < target) {
425 if (v > target) v = target;
430 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
432 double FGTurboProp::ExpSeek(double *var, double target, double accel_tau, double decel_tau)
434 // exponential delay instead of the linear delay used in Seek
437 v = (v - target) * exp ( -dt / decel_tau) + target;
438 } else if (v < target) {
439 v = (target - v) * (1 - exp ( -dt / accel_tau)) + v;
444 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
446 void FGTurboProp::SetDefaults(void)
448 // Name = "Not defined";
458 NozzlePosition = 1.0;
470 Ielu_intervent=false;
472 Idle_Max_Delay = 1.0;
475 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
478 string FGTurboProp::GetEngineLabels(const string& delimiter)
480 std::ostringstream buf;
482 buf << Name << "_N1[" << EngineNumber << "]" << delimiter
483 << Name << "_N2[" << EngineNumber << "]" << delimiter
484 << Name << "_PwrAvail[" << EngineNumber << "]" << delimiter
485 << Thruster->GetThrusterLabels(EngineNumber, delimiter);
490 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
492 string FGTurboProp::GetEngineValues(const string& delimiter)
494 std::ostringstream buf;
496 buf << PowerAvailable << delimiter
499 << Thruster->GetThrusterValues(EngineNumber,delimiter);
504 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
506 int FGTurboProp::InitRunning(void)
508 State->SuspendIntegration();
513 State->ResumeIntegration();
517 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
519 void FGTurboProp::bindmodel()
521 string property_name, base_property_name;
522 base_property_name = CreateIndexedPropertyName("propulsion/engine", EngineNumber);
523 property_name = base_property_name + "/n1";
524 PropertyManager->Tie( property_name.c_str(), &N1);
525 property_name = base_property_name + "/n2";
526 PropertyManager->Tie( property_name.c_str(), &N2);
527 property_name = base_property_name + "/reverser";
528 PropertyManager->Tie( property_name.c_str(), &Reversed);
531 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
532 // The bitmasked value choices are as follows:
533 // unset: In this case (the default) JSBSim would only print
534 // out the normally expected messages, essentially echoing
535 // the config files as they are read. If the environment
536 // variable is not set, debug_lvl is set to 1 internally
537 // 0: This requests JSBSim not to output any messages
539 // 1: This value explicity requests the normal JSBSim
541 // 2: This value asks for a message to be printed out when
542 // a class is instantiated
543 // 4: When this value is set, a message is displayed when a
544 // FGModel object executes its Run() method
545 // 8: When this value is set, various runtime state variables
546 // are printed out periodically
547 // 16: When set various parameters are sanity checked and
548 // a message is printed out when they go out of bounds
550 void FGTurboProp::Debug(int from)
552 if (debug_lvl <= 0) return;
554 if (debug_lvl & 1) { // Standard console startup message output
555 if (from == 0) { // Constructor
558 if (from == 2) { // called from Load()
559 cout << "\n ****MUJ MOTOR TURBOPROP****\n";
560 cout << "\n Engine Name: " << Name << endl;
561 cout << " MilThrust: " << MilThrust << endl;
562 cout << " IdleN1: " << IdleN1 << endl;
563 cout << " MaxN1: " << MaxN1 << endl;
568 if (debug_lvl & 2 ) { // Instantiation/Destruction notification
569 if (from == 0) cout << "Instantiated: FGTurboProp" << endl;
570 if (from == 1) cout << "Destroyed: FGTurboProp" << endl;
572 if (debug_lvl & 4 ) { // Run() method entry print for FGModel-derived objects
574 if (debug_lvl & 8 ) { // Runtime state variables
576 if (debug_lvl & 16) { // Sanity checking
578 if (debug_lvl & 64) {
579 if (from == 0) { // Constructor
580 cout << IdSrc << endl;
581 cout << IdHdr << endl;