The Expander model represents the expansion of a fluid in a volumetric machine. It is a lumped model based on performance curves. It is characterized by two flow connector for the fluid inlet and outlet and by a mechanical connector for the connection with the generator.
The assumptions for this model are:
- No dynamics ( it is considered negligible when compared to the one characterizing the heat exchanger).
- No thermal energy losses to the environment
- Isentropic efficiency based on empirical performance curve
- Filling factor based on empirical performance curve
In this model, the user has the choice of providing constant isentropic and volumetric efficiencies, or providing performance curves in the form of a Modelica function. The performance curves can be selected from the General tab with the ExpType enumeration variable.