fluid properties for specific heat capacity, thermal conductivity, density, and viscosity models. (!1616) · Merge requests · ogs / ogs

This PR presents

fluid heat capacity and thermal conductivity model creators together with constant models.
a base class, FluidProperties, to encapsulate fluid models of density, viscosity, specific heat capacity and thermal conductivity. With the class, the variables for the models are the primary variables of PDE (T, p, ...) only.
class PrimaryVariableDependentFluidProperties, which is derived from FluidProperties and which is for models with the primary variables as variables.
class PrimaryVariableDependentFluidProperties, which is also derived from FluidProperties but for models with density as one variable. It is for the models by the IAPWS.
a creator for FluidProperties.
corresponding unit tests.

fluid properties for specific heat capacity, thermal conductivity, density, and viscosity models.