DtAircraftFuelConsumptionModel Class Reference

Implements the Breguet range equation V(L/D) Range = ---—*ln(Wi/Wf) g*SFC V = Velocity L/D = Lift/Drag ratio (aerodynamic efficiency) SFC = Specific fuel consumption (engine efficiency) Wi = initial weight Wf = final weight. More...

Inheritance diagram for DtAircraftFuelConsumptionModel:

Public Member Functions
	DtAircraftFuelConsumptionModel ()
virtual	~DtAircraftFuelConsumptionModel ()
	Virtual destructor. More...
virtual bool	isValid () const
	Allows system to be configured but still warn user that something may be wrong. More...
virtual bool	addDataPoints (const DtRwAircraftEngineEfficiencyDataPointList &datapoints, double startMass, double endMass, std::ostream *errorStream=0)=0
	Configure the model with a set of data points. More...
virtual double	calculateEfficiency (double range, double speed, double startMass, double endMass) const
	Calculates an engine efficiency. More...
virtual double	calculateRange (double speed, double altitude, double startMass, double endMass) const
	Calculates the range at specific conditions. More...
virtual double	interpolateEfficiency (double speed, double altitude) const =0
	Interpolate an engine efficiency at a given speed and altitude. More...
virtual double	fuelConsumed (double range, double speed, double altitude, double mass) const
	Calculate the fuel consumed over a given range. More...
virtual bool	shouldConsumeFuel () const
	Returns true if the model should currently consume fuel. More...
virtual void	setShouldConsumeFuel (bool shouldConsume)
	Enables or disables fuel consumption. More...

Static Public Member Functions
static DtAircraftFuelConsumptionModel *	Create (const DtRwAircraftEngineEfficiencyDataPointList &datapoints)
	Factory function. More...

Protected Attributes
bool	myShouldConsumeFuel

Detailed Description

Implements the Breguet range equation V(L/D) Range = ---—*ln(Wi/Wf) g*SFC V = Velocity L/D = Lift/Drag ratio (aerodynamic efficiency) SFC = Specific fuel consumption (engine efficiency) Wi = initial weight Wf = final weight.

Subclasses implement various interpolation schemes.

Constructor & Destructor Documentation

DtAircraftFuelConsumptionModel::DtAircraftFuelConsumptionModel

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virtual DtAircraftFuelConsumptionModel::~DtAircraftFuelConsumptionModel ( )

virtual

Virtual destructor.

Member Function Documentation

static DtAircraftFuelConsumptionModel* DtAircraftFuelConsumptionModel::Create ( const DtRwAircraftEngineEfficiencyDataPointList &  datapoints )

static

Factory function.

virtual bool DtAircraftFuelConsumptionModel::isValid ( ) const

virtual

Allows system to be configured but still warn user that something may be wrong.

Reimplemented in DtBilinearInterpolationAircraftFuelConsumptionModel, and DtConstantAircraftFuelConsumptionModel.

virtual bool DtAircraftFuelConsumptionModel::addDataPoints ( const DtRwAircraftEngineEfficiencyDataPointList &  datapoints, double  startMass, double  endMass, std::ostream *  errorStream = 0  )

pure virtual

Configure the model with a set of data points.

Each data point has a range, altitude, and speed. Combined with the startMass and endMass, can be used to determine an engine efficiency.

Parameters

startMass	Starting mass of aircraft.
endMass	Ending mass of aircraft. For example if the aircraft starts out with a full fuel tank and uses all of it's fuel (the usual case for range specifications) then startMass would be the mass of the aircraft plus the mass of the full fuel tank and endMass would be the mass of the aircraft. This doesn't have to be the case though, if you knew the range when using half the fuel then you could use that.

Implemented in DtBilinearInterpolationAircraftFuelConsumptionModel, DtConstantAircraftFuelConsumptionModel, and DtNoFuelUsageAircraftFuelConsumptionModel.

virtual double DtAircraftFuelConsumptionModel::calculateEfficiency ( double  range, double  speed, double  startMass, double  endMass  ) const

virtual

Calculates an engine efficiency.

This is a function of Breguet equation and generally should not be override by subclasses.

virtual double DtAircraftFuelConsumptionModel::calculateRange ( double  speed, double  altitude, double  startMass, double  endMass  ) const

virtual

Calculates the range at specific conditions.

Reimplemented in DtNoFuelUsageAircraftFuelConsumptionModel.

virtual double DtAircraftFuelConsumptionModel::interpolateEfficiency ( double  speed, double  altitude  ) const

pure virtual

Interpolate an engine efficiency at a given speed and altitude.

Implemented in DtBilinearInterpolationAircraftFuelConsumptionModel, DtConstantAircraftFuelConsumptionModel, and DtNoFuelUsageAircraftFuelConsumptionModel.

virtual double DtAircraftFuelConsumptionModel::fuelConsumed ( double  range, double  speed, double  altitude, double  mass  ) const

virtual

Calculate the fuel consumed over a given range.

Parameters

mass	The mass of the aircraft (airframe + fuel) at the start of the movement. Does not take into account the amount of fuel the aircraft has, i.e. it may use more fuel than the aircraft has. It's up to the user to actually deal with decrementing the fuel.

Reimplemented in DtNoFuelUsageAircraftFuelConsumptionModel.

virtual bool DtAircraftFuelConsumptionModel::shouldConsumeFuel ( ) const

virtual

Returns true if the model should currently consume fuel.

Reimplemented in DtNoFuelUsageAircraftFuelConsumptionModel.

virtual void DtAircraftFuelConsumptionModel::setShouldConsumeFuel ( bool  shouldConsume )

virtual

Enables or disables fuel consumption.

Member Data Documentation

bool DtAircraftFuelConsumptionModel::myShouldConsumeFuel

protected

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

• /data/exports/nrhent7-1/nightly/docs/vrForces.vrf4-8-branch/include/vrfutil/aircraftFuelConsumptionModel.h