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"
47 #include "FGPropeller.h"
48 #include "models/FGPropulsion.h"
49 #include "models/FGAuxiliary.h"
55 static const char *IdSrc = "$Id: FGTurboProp.cpp,v 1.16 2010/02/25 05:21:36 jberndt Exp $";
56 static const char *IdHdr = ID_TURBOPROP;
58 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
60 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
62 FGTurboProp::FGTurboProp(FGFDMExec* exec, Element *el, int engine_number)
63 : FGEngine(exec, el, engine_number),
64 ITT_N1(NULL), EnginePowerRPM_N1(NULL), EnginePowerVC(NULL)
72 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
74 FGTurboProp::~FGTurboProp()
77 delete EnginePowerRPM_N1;
82 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
84 bool FGTurboProp::Load(FGFDMExec* exec, Element *el)
87 MaxStartingTime = 999999; //very big timeout -> infinite
90 // ToDo: Need to make sure units are properly accounted for below.
92 if (el->FindElement("milthrust"))
93 MilThrust = el->FindElementValueAsNumberConvertTo("milthrust","LBS");
94 if (el->FindElement("idlen1"))
95 IdleN1 = el->FindElementValueAsNumber("idlen1");
96 if (el->FindElement("idlen2"))
97 IdleN2 = el->FindElementValueAsNumber("idlen2");
98 if (el->FindElement("maxn1"))
99 MaxN1 = el->FindElementValueAsNumber("maxn1");
100 if (el->FindElement("maxn2"))
101 MaxN2 = el->FindElementValueAsNumber("maxn2");
102 if (el->FindElement("betarangeend"))
103 BetaRangeThrottleEnd = el->FindElementValueAsNumber("betarangeend")/100.0;
104 if (el->FindElement("reversemaxpower"))
105 ReverseMaxPower = el->FindElementValueAsNumber("reversemaxpower")/100.0;
107 if (el->FindElement("maxpower"))
108 MaxPower = el->FindElementValueAsNumber("maxpower");
109 if (el->FindElement("idlefuelflow"))
110 IdleFF = el->FindElementValueAsNumber("idlefuelflow");
111 if (el->FindElement("psfc"))
112 PSFC = el->FindElementValueAsNumber("psfc");
113 if (el->FindElement("n1idle_max_delay"))
114 Idle_Max_Delay = el->FindElementValueAsNumber("n1idle_max_delay");
115 if (el->FindElement("maxstartingtime"))
116 MaxStartingTime = el->FindElementValueAsNumber("maxstartingtime");
117 if (el->FindElement("startern1"))
118 StarterN1 = el->FindElementValueAsNumber("startern1");
119 if (el->FindElement("ielumaxtorque"))
120 Ielu_max_torque = el->FindElementValueAsNumber("ielumaxtorque");
121 if (el->FindElement("itt_delay"))
122 ITT_Delay = el->FindElementValueAsNumber("itt_delay");
124 Element *table_element;
126 FGPropertyManager* PropertyManager = exec->GetPropertyManager();
129 table_element = el->FindNextElement("table");
130 if (!table_element) break;
131 name = table_element->GetAttributeValue("name");
132 if (name == "EnginePowerVC") {
133 EnginePowerVC = new FGTable(PropertyManager, table_element);
134 } else if (name == "EnginePowerRPM_N1") {
135 EnginePowerRPM_N1 = new FGTable(PropertyManager, table_element);
136 } else if (name == "ITT_N1") {
137 ITT_N1 = new FGTable(PropertyManager, table_element);
139 cerr << "Unknown table type: " << name << " in turbine definition." <<
144 // Pre-calculations and initializations
147 N1_factor = MaxN1 - IdleN1;
148 N2_factor = MaxN2 - IdleN2;
149 OilTemp_degK = (Auxiliary->GetTotalTemperature() - 491.69) * 0.5555556 + 273.0;
150 if (IdleFF==-1) IdleFF = pow(MilThrust, 0.2) * 107.0; // just an estimate
152 cout << "ENG POWER:" << EnginePowerRPM_N1->GetValue(1200,90) << "\n";
157 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
158 // The main purpose of Calculate() is to determine what phase the engine should
159 // be in, then call the corresponding function.
161 double FGTurboProp::Calculate(void)
163 TAT = (Auxiliary->GetTotalTemperature() - 491.69) * 0.5555556;
164 dt = FDMExec->GetDeltaT() * Propulsion->GetRate();
166 ThrottleCmd = FCS->GetThrottleCmd(EngineNumber);
168 Prop_RPM = Thruster->GetRPM() * Thruster->GetGearRatio();
169 if (Thruster->GetType() == FGThruster::ttPropeller) {
170 ((FGPropeller*)Thruster)->SetAdvance(FCS->GetPropAdvance(EngineNumber));
171 ((FGPropeller*)Thruster)->SetFeather(FCS->GetPropFeather(EngineNumber));
172 ((FGPropeller*)Thruster)->SetReverse(Reversed);
174 ((FGPropeller*)Thruster)->SetReverseCoef(ThrottleCmd);
176 ((FGPropeller*)Thruster)->SetReverseCoef(0.0);
181 if (ThrottleCmd < BetaRangeThrottleEnd) {
182 ThrottleCmd = 0.0; // idle when in Beta-range
185 ThrottleCmd = (ThrottleCmd-BetaRangeThrottleEnd)/(1-BetaRangeThrottleEnd) * ReverseMaxPower;
189 // When trimming is finished check if user wants engine OFF or RUNNING
190 if ((phase == tpTrim) && (dt > 0)) {
191 if (Running && !Starved) {
195 OilTemp_degK = 366.0;
201 Eng_Temperature = TAT;
202 OilTemp_degK = TAT+273.15;
206 if (!Running && Starter) {
207 if (phase == tpOff) {
209 if (StartTime < 0) StartTime=0;
212 if (!Running && !Cutoff && (N1 > 15.0)) {
216 if (Cutoff && (phase != tpSpinUp)) phase = tpOff;
217 if (dt == 0) phase = tpTrim;
218 if (Starved) phase = tpOff;
219 if (Condition >= 10) {
225 if (Ielu_max_torque > 0
226 && -Ielu_max_torque > ((FGPropeller*)(Thruster))->GetTorque()
227 && ThrottleCmd >= OldThrottle ) {
228 ThrottleCmd = OldThrottle - 0.1 * dt; //IELU down
229 Ielu_intervent = true;
230 } else if (Ielu_max_torque > 0 && Ielu_intervent && ThrottleCmd >= OldThrottle) {
231 ThrottleCmd = OldThrottle;
232 ThrottleCmd = OldThrottle + 0.05 * dt; //IELU up
233 Ielu_intervent = true;
235 Ielu_intervent = false;
238 Ielu_intervent = false;
240 OldThrottle = ThrottleCmd;
243 case tpOff: Eng_HP = Off(); break;
244 case tpRun: Eng_HP = Run(); break;
245 case tpSpinUp: Eng_HP = SpinUp(); break;
246 case tpStart: Eng_HP = Start(); break;
250 //printf ("EngHP: %lf / Requi: %lf\n",Eng_HP,Prop_Required_Power);
251 PowerAvailable = (Eng_HP * hptoftlbssec) - Thruster->GetPowerRequired();
253 return Thruster->Calculate(PowerAvailable);
257 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
259 double FGTurboProp::Off(void)
261 double qbar = Auxiliary->Getqbar();
262 Running = false; EngStarting = false;
264 FuelFlow_pph = Seek(&FuelFlow_pph, 0, 800.0, 800.0);
266 //allow the air turn with generator
267 N1 = ExpSeek(&N1, qbar/15.0, Idle_Max_Delay*2.5, Idle_Max_Delay * 5);
269 OilTemp_degK = ExpSeek(&OilTemp_degK,273.15 + TAT, 400 , 400);
271 Eng_Temperature = ExpSeek(&Eng_Temperature,TAT,300,400);
272 double ITT_goal = ITT_N1->GetValue(N1,0.1) + ((N1>20) ? 0.0 : (20-N1)/20.0 * Eng_Temperature);
273 Eng_ITT_degC = ExpSeek(&Eng_ITT_degC,ITT_goal,ITT_Delay,ITT_Delay*1.2);
275 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
277 ConsumeFuel(); // for possible setting Starved = false when fuel tank
278 // is refilled (fuel crossfeed etc.)
280 if (Prop_RPM>5) return -0.012; // friction in engine when propeller spining (estimate)
284 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
286 double FGTurboProp::Run(void)
288 double thrust = 0.0, EngPower_HP, eff_coef;
289 Running = true; Starter = false; EngStarting = false;
293 N1 = ExpSeek(&N1, IdleN1 + ThrottleCmd * N1_factor, Idle_Max_Delay, Idle_Max_Delay * 2.4);
295 EngPower_HP = EnginePowerRPM_N1->GetValue(Prop_RPM,N1);
296 EngPower_HP *= EnginePowerVC->GetValue();
297 if (EngPower_HP > MaxPower) EngPower_HP = MaxPower;
299 eff_coef = 9.333 - (N1)/12; // 430%Fuel at 60%N1
300 FuelFlow_pph = PSFC * EngPower_HP * eff_coef;
302 Eng_Temperature = ExpSeek(&Eng_Temperature,Eng_ITT_degC,300,400);
303 double ITT_goal = ITT_N1->GetValue((N1-old_N1)*300+N1,1);
304 Eng_ITT_degC = ExpSeek(&Eng_ITT_degC,ITT_goal,ITT_Delay,ITT_Delay*1.2);
306 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
308 EPR = 1.0 + thrust/MilThrust;
310 OilTemp_degK = Seek(&OilTemp_degK, 353.15, 0.4-N1*0.001, 0.04);
314 if (Cutoff) phase = tpOff;
315 if (Starved) phase = tpOff;
320 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
322 double FGTurboProp::SpinUp(void)
325 Running = false; EngStarting = true;
328 if (!GeneratorPower) {
335 N1 = ExpSeek(&N1, StarterN1, Idle_Max_Delay * 6, Idle_Max_Delay * 2.4);
337 Eng_Temperature = ExpSeek(&Eng_Temperature,TAT,300,400);
338 double ITT_goal = ITT_N1->GetValue(N1,0.1) + ((N1>20) ? 0.0 : (20-N1)/20.0 * Eng_Temperature);
339 Eng_ITT_degC = ExpSeek(&Eng_ITT_degC,ITT_goal,ITT_Delay,ITT_Delay*1.2);
341 OilTemp_degK = ExpSeek(&OilTemp_degK,273.15 + TAT, 400 , 400);
343 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
344 NozzlePosition = 1.0;
346 EngPower_HP = EnginePowerRPM_N1->GetValue(Prop_RPM,N1);
347 EngPower_HP *= EnginePowerVC->GetValue();
348 if (EngPower_HP > MaxPower) EngPower_HP = MaxPower;
350 if (StartTime>=0) StartTime+=dt;
351 if (StartTime > MaxStartingTime && MaxStartingTime > 0) { //start failed due timeout
356 ConsumeFuel(); // for possible setting Starved = false when fuel tank
357 // is refilled (fuel crossfeed etc.)
362 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
364 double FGTurboProp::Start(void)
366 double EngPower_HP,eff_coef;
368 if ((N1 > 15.0) && !Starved) { // minimum 15% N2 needed for start
370 Cranking = true; // provided for sound effects signal
372 EngPower_HP = EnginePowerRPM_N1->GetValue(Prop_RPM,N1);
373 EngPower_HP *= EnginePowerVC->GetValue();
374 if (EngPower_HP > MaxPower) EngPower_HP = MaxPower;
375 N1 = ExpSeek(&N1, IdleN1*1.1, Idle_Max_Delay*4, Idle_Max_Delay * 2.4);
376 eff_coef = 9.333 - (N1)/12; // 430%Fuel at 60%N1
377 FuelFlow_pph = PSFC * EngPower_HP * eff_coef;
378 Eng_Temperature = ExpSeek(&Eng_Temperature,Eng_ITT_degC,300,400);
379 double ITT_goal = ITT_N1->GetValue((N1-old_N1)*300+N1,1);
380 Eng_ITT_degC = ExpSeek(&Eng_ITT_degC,ITT_goal,ITT_Delay,ITT_Delay*1.2);
382 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
383 OilTemp_degK = Seek(&OilTemp_degK, 353.15, 0.4-N1*0.001, 0.04);
393 } else { // no start if N2 < 15% or Starved
404 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
406 double FGTurboProp::CalcFuelNeed(void)
408 double dT = FDMExec->GetDeltaT() * Propulsion->GetRate();
409 FuelFlowRate = FuelFlow_pph / 3600.0;
410 FuelExpended = FuelFlowRate * dT;
414 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
416 double FGTurboProp::Seek(double *var, double target, double accel, double decel)
421 if (v < target) v = target;
422 } else if (v < target) {
424 if (v > target) v = target;
429 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
431 double FGTurboProp::ExpSeek(double *var, double target, double accel_tau, double decel_tau)
433 // exponential delay instead of the linear delay used in Seek
436 v = (v - target) * exp ( -dt / decel_tau) + target;
437 } else if (v < target) {
438 v = (target - v) * (1 - exp ( -dt / accel_tau)) + v;
443 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
445 void FGTurboProp::SetDefaults(void)
447 // Name = "Not defined";
457 NozzlePosition = 1.0;
469 Ielu_intervent=false;
471 Idle_Max_Delay = 1.0;
474 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
477 string FGTurboProp::GetEngineLabels(const string& delimiter)
479 std::ostringstream buf;
481 buf << Name << "_N1[" << EngineNumber << "]" << delimiter
482 << Name << "_N2[" << EngineNumber << "]" << delimiter
483 << Name << "_PwrAvail[" << EngineNumber << "]" << delimiter
484 << Thruster->GetThrusterLabels(EngineNumber, delimiter);
489 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
491 string FGTurboProp::GetEngineValues(const string& delimiter)
493 std::ostringstream buf;
495 buf << PowerAvailable << delimiter
498 << Thruster->GetThrusterValues(EngineNumber,delimiter);
503 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
505 int FGTurboProp::InitRunning(void)
507 FDMExec->SuspendIntegration();
512 FDMExec->ResumeIntegration();
516 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
518 void FGTurboProp::bindmodel()
520 string property_name, base_property_name;
521 base_property_name = CreateIndexedPropertyName("propulsion/engine", EngineNumber);
522 property_name = base_property_name + "/n1";
523 PropertyManager->Tie( property_name.c_str(), &N1);
524 property_name = base_property_name + "/n2";
525 PropertyManager->Tie( property_name.c_str(), &N2);
526 property_name = base_property_name + "/reverser";
527 PropertyManager->Tie( property_name.c_str(), &Reversed);
530 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
531 // The bitmasked value choices are as follows:
532 // unset: In this case (the default) JSBSim would only print
533 // out the normally expected messages, essentially echoing
534 // the config files as they are read. If the environment
535 // variable is not set, debug_lvl is set to 1 internally
536 // 0: This requests JSBSim not to output any messages
538 // 1: This value explicity requests the normal JSBSim
540 // 2: This value asks for a message to be printed out when
541 // a class is instantiated
542 // 4: When this value is set, a message is displayed when a
543 // FGModel object executes its Run() method
544 // 8: When this value is set, various runtime state variables
545 // are printed out periodically
546 // 16: When set various parameters are sanity checked and
547 // a message is printed out when they go out of bounds
549 void FGTurboProp::Debug(int from)
551 if (debug_lvl <= 0) return;
553 if (debug_lvl & 1) { // Standard console startup message output
554 if (from == 0) { // Constructor
557 if (from == 2) { // called from Load()
558 cout << "\n ****MUJ MOTOR TURBOPROP****\n";
559 cout << "\n Engine Name: " << Name << endl;
560 cout << " MilThrust: " << MilThrust << endl;
561 cout << " IdleN1: " << IdleN1 << endl;
562 cout << " MaxN1: " << MaxN1 << endl;
567 if (debug_lvl & 2 ) { // Instantiation/Destruction notification
568 if (from == 0) cout << "Instantiated: FGTurboProp" << endl;
569 if (from == 1) cout << "Destroyed: FGTurboProp" << endl;
571 if (debug_lvl & 4 ) { // Run() method entry print for FGModel-derived objects
573 if (debug_lvl & 8 ) { // Runtime state variables
575 if (debug_lvl & 16) { // Sanity checking
577 if (debug_lvl & 64) {
578 if (from == 0) { // Constructor
579 cout << IdSrc << endl;
580 cout << IdHdr << endl;