fly/flightgear
1
0
Fork 0
Code Activity

Latest JSBSim changes.

Browse source
This commit is contained in:
david 2001-12-14 23:57:05 +00:00
parent fbccfab5ff
commit 26c6f3f407
3 changed files with 26 additions and 12 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

28
src/FDM/JSBSim/FGPiston.cpp
View file

@ -1,7 +1,8 @@
/*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
Module: FGPiston.cpp Module: FGPiston.cpp
Author: Jon S. Berndt Author: Jon S. Berndt, JSBSim framework
Dave Luff, Piston engine model
Date started: 09/12/2000 Date started: 09/12/2000
Purpose: This module models a Piston engine Purpose: This module models a Piston engine
@ -85,6 +86,7 @@ FGPiston::FGPiston(FGFDMExec* exec, FGConfigFile* Eng_cfg) : FGEngine(exec),
crank_counter = 0; crank_counter = 0;
EngineNumber = 0; EngineNumber = 0;
OilTemp_degK = 298; OilTemp_degK = 298;
ManifoldPressure_inHg = Atmosphere->GetPressure() * 0.014138; // psf to in Hg
dt = State->Getdt(); dt = State->Getdt();
@ -285,8 +287,12 @@ void FGPiston::doEngineStartup(void)
void FGPiston::doManifoldPressure(void) void FGPiston::doManifoldPressure(void)
{ {
ManifoldPressure_inHg = MinManifoldPressure_inHg + if (Running || Cranking) {
(Throttle * (MaxManifoldPressure_inHg - MinManifoldPressure_inHg)); ManifoldPressure_inHg = MinManifoldPressure_inHg +
(Throttle * (MaxManifoldPressure_inHg - MinManifoldPressure_inHg));
} else {
ManifoldPressure_inHg = Atmosphere->GetPressure() * 0.014138; // psf to in Hg
}
} }
//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
@ -390,11 +396,19 @@ void FGPiston::doEnginePower(void)
void FGPiston::doEGT(void) void FGPiston::doEGT(void)
{ {
double delta_T_exhaust = 0.0;
double heat_capacity_exhaust;
double enthalpy_exhaust;
combustion_efficiency = Lookup_Combustion_Efficiency->GetValue(equivalence_ratio); combustion_efficiency = Lookup_Combustion_Efficiency->GetValue(equivalence_ratio);
double enthalpy_exhaust = m_dot_fuel * calorific_value_fuel * enthalpy_exhaust = m_dot_fuel * calorific_value_fuel * combustion_efficiency * 0.33;
combustion_efficiency * 0.33; heat_capacity_exhaust = (Cp_air * m_dot_air) + (Cp_fuel * m_dot_fuel);
double heat_capacity_exhaust = (Cp_air * m_dot_air) + (Cp_fuel * m_dot_fuel);
double delta_T_exhaust = enthalpy_exhaust / heat_capacity_exhaust; if (heat_capacity_exhaust >= 0.0000001)
delta_T_exhaust = enthalpy_exhaust / heat_capacity_exhaust;
else
delta_T_exhaust = 0.0;
ExhaustGasTemp_degK = T_amb + delta_T_exhaust; ExhaustGasTemp_degK = T_amb + delta_T_exhaust;
ExhaustGasTemp_degK *= 0.444 + ((0.544 - 0.444) * Percentage_Power / 100.0); ExhaustGasTemp_degK *= 0.444 + ((0.544 - 0.444) * Percentage_Power / 100.0);
} }

8
src/FDM/JSBSim/FGPropeller.cpp
View file

@ -147,8 +147,8 @@ double FGPropeller::Calculate(double PowerAvailable)
if (P_Factor > 0.0001) { if (P_Factor > 0.0001) {
alpha = fdmex->GetTranslation()->Getalpha(); alpha = fdmex->GetTranslation()->Getalpha();
beta = fdmex->GetTranslation()->Getbeta(); beta = fdmex->GetTranslation()->Getbeta();
SetActingLocationY( GetLocationY() + P_Factor*alpha*fabs(Sense)/Sense); SetActingLocationY( GetLocationY() + P_Factor*alpha*Sense);
SetActingLocationZ( GetLocationZ() + P_Factor*beta*fabs(Sense)/Sense); SetActingLocationZ( GetLocationZ() + P_Factor*beta*Sense);
} else if (P_Factor < 0.000) { } else if (P_Factor < 0.000) {
cerr << "P-Factor value in config file must be greater than zero" << endl; cerr << "P-Factor value in config file must be greater than zero" << endl;
} }
@ -161,7 +161,7 @@ double FGPropeller::Calculate(double PowerAvailable)
// natural axis of the engine. The transform takes place in the base class // natural axis of the engine. The transform takes place in the base class
// FGForce::GetBodyForces() function. // FGForce::GetBodyForces() function.
vH(eX) = Ixx*omega*fabs(Sense)/Sense; vH(eX) = Ixx*omega*Sense;
vH(eY) = 0.0; vH(eY) = 0.0;
vH(eZ) = 0.0; vH(eZ) = 0.0;
@ -208,7 +208,7 @@ double FGPropeller::GetPowerRequired(void)
PowerRequired = cPReq*RPS*RPS*RPS*Diameter*Diameter*Diameter*Diameter PowerRequired = cPReq*RPS*RPS*RPS*Diameter*Diameter*Diameter*Diameter
*Diameter*rho; *Diameter*rho;
vTorque(eX) = PowerRequired / ((RPM/60)*2.0*M_PI); vTorque(eX) = -Sense*PowerRequired / (RPS*2.0*M_PI);
return PowerRequired; return PowerRequired;
} }

2
src/FDM/JSBSim/FGPropulsion.cpp
View file

@ -317,7 +317,7 @@ bool FGPropulsion::Load(FGConfigFile* AC_cfg)
if (thrType == "FG_PROPELLER" && P_Factor > 0.001) { if (thrType == "FG_PROPELLER" && P_Factor > 0.001) {
((FGPropeller*)Thrusters[numThrusters])->SetPFactor(P_Factor); ((FGPropeller*)Thrusters[numThrusters])->SetPFactor(P_Factor);
if (debug_lvl > 0) cout << " P-Factor: " << P_Factor << endl; if (debug_lvl > 0) cout << " P-Factor: " << P_Factor << endl;
((FGPropeller*)Thrusters[numThrusters])->SetSense(Sense); ((FGPropeller*)Thrusters[numThrusters])->SetSense(fabs(Sense)/Sense);
if (debug_lvl > 0) cout << " Sense: " << Sense << endl; if (debug_lvl > 0) cout << " Sense: " << Sense << endl;
} }
Thrusters[numThrusters]->SetdeltaT(dt*rate); Thrusters[numThrusters]->SetdeltaT(dt*rate);