.ThermoSysPro.Properties.Common.ThermoFluidSpecial.ThermoProperties_dT .ThermoSysPro.Properties.Common.ThermoFluidSpecial.ThermoProperties_dTA base class for medium property models which use density and temperature as dynamic states. This is a reasonable model for fluids that can be in the gas, liquid and two-phase region. The model is numerically not well suited for liquids except if the pressure is always above approx. 80% of the critical pressure.