void FGRocket::ConsumeFuel(void)
{
unsigned int i;
FGTank* Tank;
bool haveOxTanks = false;
double Fshortage=0, Oshortage=0, TanksWithFuel=0, TanksWithOxidizer=0;
if (FuelFreeze) return;
if (TrimMode) return;
// Count how many assigned tanks have fuel for this engine at this time.
// If there is/are fuel tanks but no oxidizer tanks, this indicates
// a solid rocket is being modeled.
for (i=0; i<SourceTanks.size(); i++) {
Tank = Propulsion->GetTank(SourceTanks[i]);
switch(Tank->GetType()) {
case FGTank::ttFUEL:
if (Tank->GetContents() > 0.0 && Tank->GetSelected()) ++TanksWithFuel;
break;
case FGTank::ttOXIDIZER:
haveOxTanks = true;
if (Tank->GetContents() > 0.0 && Tank->GetSelected()) ++TanksWithOxidizer;
break;
}
}
// If this engine has burned out, it is starved.
if (TanksWithFuel==0 || (haveOxTanks && TanksWithOxidizer==0)) {
Starved = true;
return;
}
// Expend fuel from the engine's tanks if the tank is selected as a source
// for this engine.
double fuelNeedPerTank = CalcFuelNeed()/TanksWithFuel;
double oxiNeedPerTank = CalcOxidizerNeed()/TanksWithOxidizer;
for (i=0; i<SourceTanks.size(); i++) {
Tank = Propulsion->GetTank(SourceTanks[i]);
if ( ! Tank->GetSelected()) continue; // If this tank is not selected as a source, skip it.
switch(Tank->GetType()) {
case FGTank::ttFUEL:
Fshortage += Tank->Drain(2.0*fuelNeedPerTank - previousFuelNeedPerTank);
previousFuelNeedPerTank = fuelNeedPerTank;
break;
case FGTank::ttOXIDIZER:
Oshortage += Tank->Drain(2.0*oxiNeedPerTank - previousOxiNeedPerTank);
previousOxiNeedPerTank = oxiNeedPerTank;
break;
}
}
if (Fshortage < 0.00 || (haveOxTanks && Oshortage < 0.00)) Starved = true;
else Starved = false;
}
string FGPropulsion::GetPropulsionTankReport()
{
string out="";
stringstream outstream;
/*const FGMatrix33& mTkI =*/ CalculateTankInertias();
for (unsigned int i=0; i<numTanks; i++)
{
FGTank* tank = Tanks[i];
string tankname="";
if (tank->GetType() == FGTank::ttFUEL && tank->GetGrainType() != FGTank::gtUNKNOWN) {
tankname = "Solid Fuel";
} else if (tank->GetType() == FGTank::ttFUEL) {
tankname = "Fuel";
} else if (tank->GetType() == FGTank::ttOXIDIZER) {
tankname = "Oxidizer";
} else {
tankname = "(Unknown tank type)";
}
outstream << highint << left << setw(4) << i << setw(30) << tankname << normint
<< right << setw(10) << tank->GetContents() << setw(8) << tank->GetXYZ(eX)
<< setw(8) << tank->GetXYZ(eY) << setw(8) << tank->GetXYZ(eZ)
<< setw(12) << tank->GetIxx() << setw(12) << tank->GetIyy()
<< setw(12) << tank->GetIzz() << endl;
}
return outstream.str();
}
void FGPropulsion::ConsumeFuel(FGEngine* engine)
{
if (FuelFreeze) return;
if (FDMExec->GetTrimStatus()) return;
unsigned int TanksWithFuel=0, CurrentFuelTankPriority=1;
unsigned int TanksWithOxidizer=0, CurrentOxidizerTankPriority=1;
vector <int> FeedListFuel, FeedListOxi;
bool Starved = true; // Initially set Starved to true. Set to false in code below.
bool hasOxTanks = false;
// For this engine,
// 1) Count how many fuel tanks with the current priority level have fuel
// 2) If there none, then try next lower priority (higher number) - that is,
// increment CurrentPriority.
// 3) Build the feed list.
// 4) Do the same for oxidizer tanks, if needed.
// Process fuel tanks, if any
while ((TanksWithFuel == 0) && (CurrentFuelTankPriority <= numTanks)) {
for (unsigned int i=0; i<engine->GetNumSourceTanks(); i++) {
unsigned int TankId = engine->GetSourceTank(i);
FGTank* Tank = Tanks[TankId];
unsigned int TankPriority = Tank->GetPriority();
if (TankPriority != 0) {
switch(Tank->GetType()) {
case FGTank::ttFUEL:
if ((Tank->GetContents() > 0.0) && Tank->GetSelected() && (TankPriority == CurrentFuelTankPriority)) {
TanksWithFuel++;
Starved = false;
FeedListFuel.push_back(TankId);
}
break;
case FGTank::ttOXIDIZER:
// Skip this here (done below)
break;
}
}
}
if (TanksWithFuel == 0) CurrentFuelTankPriority++; // No tanks at this priority, try next priority
}
bool FuelStarved = Starved;
Starved = true;
// Process Oxidizer tanks, if any
if (engine->GetType() == FGEngine::etRocket) {
while ((TanksWithOxidizer == 0) && (CurrentOxidizerTankPriority <= numTanks)) {
for (unsigned int i=0; i<engine->GetNumSourceTanks(); i++) {
unsigned int TankId = engine->GetSourceTank(i);
FGTank* Tank = Tanks[TankId];
unsigned int TankPriority = Tank->GetPriority();
if (TankPriority != 0) {
switch(Tank->GetType()) {
case FGTank::ttFUEL:
// Skip this here (done above)
break;
case FGTank::ttOXIDIZER:
hasOxTanks = true;
if (Tank->GetContents() > 0.0 && Tank->GetSelected() && TankPriority == CurrentOxidizerTankPriority) {
TanksWithOxidizer++;
if (TanksWithFuel > 0) Starved = false;
FeedListOxi.push_back(TankId);
}
break;
}
}
}
if (TanksWithOxidizer == 0) CurrentOxidizerTankPriority++; // No tanks at this priority, try next priority
}
}
bool OxiStarved = Starved;
engine->SetStarved(FuelStarved || (hasOxTanks && OxiStarved)); // Tanks can be refilled, so be sure to reset engine Starved flag here.
// No fuel or fuel/oxidizer found at any priority!
// if (Starved) return;
if (FuelStarved || (hasOxTanks && OxiStarved)) return;
double FuelToBurn = engine->CalcFuelNeed(); // How much fuel does this engine need?
double FuelNeededPerTank = FuelToBurn / TanksWithFuel; // Determine fuel needed per tank.
for (unsigned int i=0; i<FeedListFuel.size(); i++) {
Tanks[FeedListFuel[i]]->Drain(FuelNeededPerTank);
}
if (engine->GetType() == FGEngine::etRocket) {
double OxidizerToBurn = engine->CalcOxidizerNeed(); // How much fuel does this engine need?
double OxidizerNeededPerTank = 0;
if (TanksWithOxidizer > 0) OxidizerNeededPerTank = OxidizerToBurn / TanksWithOxidizer; // Determine fuel needed per tank.
for (unsigned int i=0; i<FeedListOxi.size(); i++) {
Tanks[FeedListOxi[i]]->Drain(OxidizerNeededPerTank);
}
}
}
