OpenFOAM v11 User Guide - Chapter 8 Models and physical properties

Chapter 8 Models and physical properties

OpenFOAM includes a large range of solvers, each designed for a specific class of flow, as described in section 3.6 . Each solver uses a particular set of models which calculate physical properties and simulate phenomena like transport, turbulence, thermal radiation, etc.

From OpenFOAM v10 onwards, a distinction is made between material properties and models for phenomena such as those mentioned above. Properties are specified in physicalProperties file in the constant directory. In the case of fluids, properties in physicalProperties relate to a fluid at rest. They are the properties you might look up from a table in a book, so can be dependent on temperature , based on some function.

Properties described in physicalProperties do not include any dependency on the flow itself. For example, turbulence, visco-elasticity and the variation of viscosity with strain-rate, are all specified in a momentumTransport file in the constant directory. This chapter includes a description of models for viscosity which are dependent on strain-rate in section 8.3 and turbulence models in section 8.2 . Thermophysical models, which are specified in the physicalProperties file (since they represent temperature dependency of properties) are described in section 8.1 .