Turboprop engine model. More...

#include <FGTurboProp.h>

Inheritance diagram for FGTurboProp:

Collaboration diagram for FGTurboProp:

Public Types
enum	phaseType { tpOff, tpRun, tpSpinUp, tpStart, tpStall, tpSeize, tpTrim }
Public Member Functions
	FGTurboProp (FGFDMExec Executive, Element el, int engine_number, struct Inputs &input)
	Constructor.
	~FGTurboProp ()
	Destructor.
double	CalcFuelNeed (void)
	The fuel need is calculated based on power levels and flow rate for that power level.
void	Calculate (void)
	Calculates the thrust of the engine, and other engine functions.
double	ExpSeek (double *var, double target, double accel, double decel)
int	GetCondition (void) const
bool	GetCutoff (void) const
std::string	GetEngineLabels (const std::string &delimiter)
std::string	GetEngineValues (const std::string &delimiter)
double	GetEngStarting (void) const
double	GetEPR (void) const
bool	GetFire (void) const
bool	GetGeneratorPower (void) const
bool	GetIeluIntervent (void) const
double	GetIeluThrottle (void) const
int	GetIgnition (void) const
double	GetInlet (void) const
double	GetITT (void) const
double	GetN1 (void) const
double	GetN2 (void) const
double	GetNozzle (void) const
double	getOilPressure_psi () const
double	getOilTemp_degF (void)
bool	GetOvertemp (void) const
phaseType	GetPhase (void) const
double	GetPowerAvailable (void) const
bool	GetReversed (void) const
double	GetRPM (void) const
int	InitRunning (void)
double	Seek (double *var, double target, double accel, double decel)
void	SetCondition (bool c)
void	SetCutoff (bool cutoff)
void	SetEPR (double epr)
void	SetGeneratorPower (bool gp)
void	SetIgnition (int ignition)
void	SetPhase (phaseType p)
void	SetReverse (bool reversed)

Detailed Description

For an example of this model in use see the file: engine/engtm601.xml

Configuration parameters:

milthrust   [LBS]
idlen1      [%]
maxn1       [%]
betarangeend[%]
    if ThrottleCmd < betarangeend/100.0 then engine power=idle, propeller pitch
    is controled by ThrottleCmd (between MINPITCH and  REVERSEPITCH).
    if ThrottleCmd > betarangeend/100.0 then engine power increases up to max reverse power
reversemaxpower [%]
    max engine power in reverse mode
maxpower    [HP]
psfc power specific fuel consumption [pph/HP] for N1=100%
n1idle_max_delay [-] time constant for N1 change
maxstartenginetime [sec]
    after this time the automatic starting cycle is interrupted when the engine
    doesn't start (0=automatic starting not present)
startern1   [%]
    when starting starter spin up engine to this spin
ielumaxtorque [lb.ft]
    if torque>ielumaxtorque limiters decrease the throttle
    (ielu = Integrated Electronic Limiter Unit)
itt_delay [-] time constant for ITT change
    (ITT = Inter Turbine Temperature)

Definition at line 95 of file FGTurboProp.h.

Constructor & Destructor Documentation

FGTurboProp	(	FGFDMExec *	Executive,
		Element *	el,
		int	engine_number,
		struct Inputs &	input
	)

Parameters:

Executive	pointer to executive structure
el	pointer to the XML element representing the turbine engine
engine_number	engine number

Definition at line 63 of file FGTurboProp.cpp.

  : FGEngine(exec, el, engine_number, input),
    ITT_N1(NULL), EnginePowerRPM_N1(NULL), EnginePowerVC(NULL)
{
  SetDefaults();
  thrusterType = Thruster->GetType();

  Load(exec, el);
  bindmodel();
  Debug(0);
}

Member Function Documentation

double CalcFuelNeed ( void ) [virtual]

It is also turned from a rate into an actual amount (pounds) by multiplying it by the delta T and the rate.

Returns:: Total fuel requirement for this engine in pounds.

Reimplemented from FGEngine.

Definition at line 409 of file FGTurboProp.cpp.

{
  FuelFlowRate = FuelFlow_pph / 3600.0;
  FuelExpended = FuelFlowRate * in.TotalDeltaT;
  if (!Starved) FuelUsedLbs += FuelExpended;
  return FuelExpended;
}

void Calculate ( void ) [virtual]

Implements FGEngine.

Definition at line 165 of file FGTurboProp.cpp.

{
  RunPreFunctions();

  TAT = in.TAT_c;

  ThrottlePos = in.ThrottlePos[EngineNumber];

/* The thruster controls the engine RPM because it encapsulates the gear ratio and other transmission variables */
  RPM = Thruster->GetEngineRPM();
  if (thrusterType == FGThruster::ttPropeller) {
    ((FGPropeller*)Thruster)->SetAdvance(in.PropAdvance[EngineNumber]);
    ((FGPropeller*)Thruster)->SetFeather(in.PropFeather[EngineNumber]);
    ((FGPropeller*)Thruster)->SetReverse(Reversed);
    if (Reversed) {
      ((FGPropeller*)Thruster)->SetReverseCoef(ThrottlePos);
    } else {
      ((FGPropeller*)Thruster)->SetReverseCoef(0.0);
    }

    if (Reversed) {
      if (ThrottlePos < BetaRangeThrottleEnd) {
          ThrottlePos = 0.0;  // idle when in Beta-range
      } else {
        // when reversed:
        ThrottlePos = (ThrottlePos-BetaRangeThrottleEnd)/(1-BetaRangeThrottleEnd) * ReverseMaxPower;
      }
    }
  }

  // When trimming is finished check if user wants engine OFF or RUNNING
  if ((phase == tpTrim) && (in.TotalDeltaT > 0)) {
    if (Running && !Starved) {
      phase = tpRun;
      N2 = IdleN2;
      N1 = IdleN1;
      OilTemp_degK = 366.0;
      Cutoff = false;
    } else {
      phase = tpOff;
      Cutoff = true;
      Eng_ITT_degC = TAT;
      Eng_Temperature = TAT;
      OilTemp_degK = TAT+273.15;
    }
  }

  if (!Running && Starter) {
    if (phase == tpOff) {
      phase = tpSpinUp;
      if (StartTime < 0) StartTime=0;
    }
  }
  if (!Running && !Cutoff && (N1 > 15.0)) {
    phase = tpStart;
    StartTime = -1;
  }
  if (Cutoff && (phase != tpSpinUp)) phase = tpOff;
  if (in.TotalDeltaT == 0) phase = tpTrim;
  if (Starved) phase = tpOff;
  if (Condition >= 10) {
    phase = tpOff;
    StartTime=-1;
  }

  // limiter intervention wanted?
  if (Ielu_max_torque > 0.0) {
    double torque = 0.0;
    
    if (thrusterType == FGThruster::ttPropeller) {
      torque = ((FGPropeller*)(Thruster))->GetTorque();
    } else if (thrusterType == FGThruster::ttRotor) {
      torque = ((FGRotor*)(Thruster))->GetTorque();
    }

    if (Condition < 1) {
      if ( abs(torque) > Ielu_max_torque && ThrottlePos >= OldThrottle ) {
        ThrottlePos = OldThrottle - 0.1 * in.TotalDeltaT; //IELU down
        Ielu_intervent = true;
      } else if ( Ielu_intervent && ThrottlePos >= OldThrottle) {
        ThrottlePos = OldThrottle + 0.05 * in.TotalDeltaT; //IELU up
        Ielu_intervent = true;
      } else {
        Ielu_intervent = false;
      }
    } else {
      Ielu_intervent = false;
    }
    OldThrottle = ThrottlePos;
  }

  switch (phase) {
    case tpOff:    HP = Off(); break;
    case tpRun:    HP = Run(); break;
    case tpSpinUp: HP = SpinUp(); break;
    case tpStart:  HP = Start(); break;
    default: HP = 0;
  }
 
  LoadThrusterInputs();
  Thruster->Calculate(HP * hptoftlbssec);

  RunPostFunctions();
}

The documentation for this class was generated from the following files:

FGTurboProp Class Reference

Public Types

Public Member Functions

Detailed Description

Configuration parameters:

Constructor & Destructor Documentation

Member Function Documentation