.TILMedia.UsersGuide.SubstanceRecord

Information

Every substance model contains a substance record as replaceable parameter for the object-oriented calculation of thermo-physical properties. The substance record contains the following parameters:

• fixedMixingRatio - Boolean = true, if mixing ratio fixed during simulation.
• nc_propertyCalculation - Integer with number of components which are calculated.
• "substanceNames" - gasNames, liquidNames, etc. Array which lists the substance names.
• mixingRatio_propertyCalculation - Array with the mixing ratio of all substances.
• condensingIndex - Only for gas mixtures: Integer with the index of the component that can condense.

To access the properties of an additional substance, it is recommended to create a new substance record. A new substance record is easily created by duplicating the substance record of an existing medium (e.g. "TILMedia.VLEFluidTypes.TILMedia_R134a"). To assign the new substance, the vleFluidNames parameter has to be changed to the new substance name (e.g. "TILMedia.TILMedia_R1233ZD"), included in the list of available substances. In the record, the parameters listed above have to be specified, using the modifier (brackets behind the base class) of the new substance record. An example of a user-defined substance record is shown below:

Pure substance example:

record TILMedia_R1233ZDE "TILMedia.R1233ZDE"
extends TILMedia.VLEFluidTypes.BaseVLEFluid(
final fixedMixingRatio=true,
final nc_propertyCalculation=1,
final vleFluidNames={"TILMedia.R1233ZDE"},
final mixingRatio_propertyCalculation={1});
end TILMedia_R1233ZDE;

Mixture example:

record TILMediaXTR_MyGasMixture "MyGasMixture"
extends TILMedia.GasTypes.BaseGas(
final fixedMixingRatio=false,
final nc_propertyCalculation=4,
final gasNames={"TILMediaXTR.Water", "TILMediaXTR.Oxygen", "TILMediaXTR.Nitrogen", "TILMediaXTR.Carbon_Dioxide"},
final condensingIndex=1,
final mixingRatio_propertyCalculation={0.001,0.25,0.75,0.001});
end TILMediaXTR_MyGasMixture;

The defined mixingRatio_propertyCalculation describes the default mass fractions of all components. It is possible to give other and also time varying mass fractions xi for mixtures during a simulation. This array xi contains only the independent number of mass fractions, therefore it equals the number of components nc minus one.

All available substance names are listed in the user's guide: Substance Names.