Updated to match changes in radiostack.[ch]xx

[flightgear.git] / src / FDM / JSBSim / FGPropeller.cpp

diff --git a/src/FDM/JSBSim/FGPropeller.cpp b/src/FDM/JSBSim/FGPropeller.cpp
index 92e4c5340ca088dceb0cffcb6d94d84946630a1d..1bd9118ef6de4cfe8401b8e1d437f923c182d4aa 100644 (file)
--- a/src/FDM/JSBSim/FGPropeller.cpp
+++ b/src/FDM/JSBSim/FGPropeller.cpp
@@ -127,7 +127,7 @@ FGPropeller::~FGPropeller()
 double FGPropeller::Calculate(double PowerAvailable)
 {
   double J, C_Thrust, omega;
-  double Vel = fdmex->GetTranslation()->GetvAeroUVW(eU);
+  double Vel = fdmex->GetTranslation()->GetAeroUVW(eU);
   double rho = fdmex->GetAtmosphere()->GetDensity();
   double RPS = RPM/60.0;
   double alpha, beta;
@@ -147,21 +147,28 @@ double FGPropeller::Calculate(double PowerAvailable)
   if (P_Factor > 0.0001) {
     alpha = fdmex->GetTranslation()->Getalpha();
     beta  = fdmex->GetTranslation()->Getbeta();
-    SetActingLocationY( GetLocationY() + P_Factor*alpha*fabs(Sense)/Sense);
-    SetActingLocationZ( GetLocationZ() + P_Factor*beta*fabs(Sense)/Sense);
+    SetActingLocationY( GetLocationY() + P_Factor*alpha*Sense);
+    SetActingLocationZ( GetLocationZ() + P_Factor*beta*Sense);
   } else if (P_Factor < 0.000) {
     cerr << "P-Factor value in config file must be greater than zero" << endl;
   }
 
   Thrust = C_Thrust*RPS*RPS*Diameter*Diameter*Diameter*Diameter*rho;
-  vFn(1) = Thrust;
   omega = RPS*2.0*M_PI;
 
+  // Check for windmilling.
+  double radius = Diameter * 0.375; // 75% of radius
+  double windmill_cutoff = tan(Pitch * 1.745329E-2) * omega * radius;
+  if (Vel > windmill_cutoff)
+    Thrust = -Thrust;
+
+  vFn(1) = Thrust;
+
   // The Ixx value and rotation speed given below are for rotation about the
   // natural axis of the engine. The transform takes place in the base class
   // FGForce::GetBodyForces() function.
 
-  vH(eX) = Ixx*omega*fabs(Sense)/Sense;
+  vH(eX) = Ixx*omega*Sense;
   vH(eY) = 0.0;
   vH(eZ) = 0.0;
 
@@ -170,6 +177,12 @@ double FGPropeller::Calculate(double PowerAvailable)
   ExcessTorque = PowerAvailable / omega;
   RPM = (RPS + ((ExcessTorque / Ixx) / (2.0 * M_PI)) * deltaT) * 60.0;
 
+                               // The friction from the engine should
+                               // stop it somewhere; I chose an
+                               // arbitrary point.
+  if (RPM < 5.0)
+    RPM = 0;
+
   vMn = fdmex->GetRotation()->GetPQR()*vH + vTorque*Sense;
 
   return Thrust; // return thrust in pounds
@@ -183,10 +196,11 @@ double FGPropeller::GetPowerRequired(void)
 
   double cPReq, RPS = RPM / 60.0;
 
-  double J = fdmex->GetTranslation()->GetvAeroUVW(eU) / (Diameter * RPS);
+  double J = fdmex->GetTranslation()->GetAeroUVW(eU) / (Diameter * RPS);
   double rho = fdmex->GetAtmosphere()->GetDensity();
 
   if (MaxPitch == MinPitch) { // Fixed pitch prop
+    Pitch = MinPitch;
     cPReq = cPower->GetValue(J);
   } else {                    // Variable pitch prop
     double advance = fdmex->GetFCS()->GetPropAdvance(ThrusterNumber);
@@ -208,7 +222,7 @@ double FGPropeller::GetPowerRequired(void)
 
   PowerRequired = cPReq*RPS*RPS*RPS*Diameter*Diameter*Diameter*Diameter
                                                        *Diameter*rho;
-  vTorque(eX) = PowerRequired / ((RPM/60)*2.0*M_PI);
+  vTorque(eX) = -Sense*PowerRequired / (RPS*2.0*M_PI);
 
   return PowerRequired;
 }
@@ -272,5 +286,11 @@ void FGPropeller::Debug(int from)
   }
   if (debug_lvl & 16) { // Sanity checking
   }
+  if (debug_lvl & 64) {
+    if (from == 0) { // Constructor
+      cout << IdSrc << endl;
+      cout << IdHdr << endl;
+    }
+  }
 }