specific heat capacity at constant volume as function of density and temperature
function cv_dT extends Modelica.Icons.Function; input Units.SI.Density d "density"; input Units.SI.Temperature T "temperature"; input Integer phase = 0 "2 for two-phase, 1 for one-phase, 0 if not known"; input Integer region = 0 "if 0, region is unknown, otherwise known and this input"; output Units.SI.SpecificHeatCapacity cv "specific heat capacity"; end cv_dT;