Fuel Source Thermal Model

Class in Zendir.Classes | Inherits from ThermalModel

Declaration

class FuelSourceThermalModel;

Description

A thermal model specifically designed for fuel tanks that uses the ideal gas law to model temperature changes during fuel transfer operations. When fuel flows in or out of a tank, the gas expansion or compression causes temperature changes that this model captures using adiabatic process equations.

The model tracks the ullage volume (gas space above liquid propellant) and computes pressure and temperature changes based on the ideal gas law (PV = nRT) and adiabatic relations (T2/T1 = (V1/V2)^(gamma-1)).

Properties

Declared	Description
FuelDensity	The density of the liquid fuel in the tank.
GammaRatio	The heat capacity ratio (gamma = Cp/Cv) for the pressurant gas.
GasConstant	The specific gas constant for the pressurant gas (e.g., nitrogen, helium).
GasMass	The mass of pressurant gas in the ullage space, calculated frominitial conditions using the ideal gas law.
GasSpecificHeat	The specific heat capacity at constant pressure for the pressurant gas.
In_FuelAmountMsg	Input fuel amount message from the linked fuel source.
InitialPressure	The initial pressure of the pressurant gas in the tank.
InitialUllageVolume	The initial ullage volume when the model was initialised.
InletTemperature	Temperature (K) of incoming propellant during fill. When > 0, used withfor training-grade inlet enthalpy: ṁ·cp·(T_in − T_gas).Default 0 disables this term (preserves legacy compression-only ullage behaviour); transfer/fill presets e.g.sets a positive inlet temperature.
MinimumUllageVolume	The minimum ullage volume to prevent numerical instabilitieswhen the tank is nearly full.
Out_FuelThermalMsg	Output fuel thermal message containing the thermal and pressure dataproduced by the fuel thermal model.
TankPressure	The current tank pressure computed from the ideal gas law.
TankVolume	The total volume of the fuel tank, calculated from tank geometry.
UllageVolume	The current ullage volume (gas space above liquid propellant)

Inherited	Description
AnalysisModel	The analysis model type used for this thermal model, which determineshow the thermal calculations are performed.
Emissivity	The emissivity of the object that this model isattached to, for radiative heat transfer calculations.
EnableSpaceRadiation	A flag whether to radiate any remaining heat as a remainder of thesurface area if no connections are present to space.
IdealTemperature	The ideal temperature of the object that this model isattached to, for thermal management calculations.
IsEnabled	Is true if the object is currently enabled.
Name	The display name or tag of this object.
NetPower	The net power of the object that this model is attached to,for thermal calculations. This is the total power generatedminus the total power lost through radiation and is used forthe calculation of the transfer.
Out_ThermalMsg	Output thermal message containing the thermal data produced bythe system.
Parent	The currently attached parent object.
PowerGeneration	The total amount of power generated internally by the objectthat this model is attached to, for thermal calculations.Positive for heating, negative for cooling (e.g. fuel tank gas expansion).
SpecificHeatCapacity	The specific heat capacity of the object that this model isattached to, for thermal calculations.
SurfaceArea	The total surface area of the object that this model isattached to, for radiative heat transfer calculations.
Temperature	The current temperature of the object that this model isattached to.
TemperatureDot	The change in temperature of the object that this model isattached to, for thermal calculations over time.
ThermalConductivity	The thermal conductivity of the object that this model isattached to, for thermal calculations.
Thickness	The thickness of the object that this model isattached to, for thermal calculations.

Methods

Declared	Description
ConfigureAsHelium	Applies .
ConfigureAsHydrazine	Applies .
ConfigureAsMmhN2o4	Applies .
ConfigureAsNitrogen	Applies .
ConfigureAsXenon	Applies .
GetTankPressure	Gets the current tank pressure computed from the ideal gas law.
GetUllageVolume	Gets the current ullage volume.
InitialiseUllageState	Initialises the ullage state based on the current fuel source configuration.This calculates the initial ullage volume and gas mass for subsequentthermodynamic calculations.

Inherited	Description
Connect	Connects this thermal model to another thermal model with the specifiedsurface area and connection type.
Disconnect	Disconnects two thermal models, removing any thermal connections between them.
FindParentWithID	Returns an attached parent that satisfies the specified ID.
FindParentWithType	Returns an attached parent that satisfies the specified type.
FindRootWithID	Returns a root object that satisfies the specified ID.
FindRootWithType	Returns a root object that satisfies the specified type.
GetRootConnectionCount	Gets the number of thermal connections associated with the root objectthat this model is attached to.
GetRootModels	Gets the thermal models associated with a given physical object, based onthe root object that this model is attached to.
GetTotalConnectionArea	Gets the total connection area for a given thermal model.
Initialise	Loads the thermal model for a lookup analysis model. This willattempt to load the CSV file specified in the file path. Thisassumes the first column is time and the ‘indexed’ column is temperature.