Material Properties

The detailed behavior of materials under the influence of flow conditions, such as pressure or temperature, can have a critical effect on the accuracy of CFD predictions. ANSYS CFX software provides a wide range of material modeling options to ensure nothing stands in the way of achieving the highest fidelity solutions possible.

ANSYS CFX comes with a rich database of material properties for a large range of liquids, gases, and solids. Both ideal and real fluid behavior can be modeled using well-established and advanced equations of state. Numerous relations are available for viscosity and conductivity variations, from Sutherland’s formula to models based on kinetic theory. For non-Newtonian fluids, an ample selection of viscosity models is provided to account for their shear-rate dependent behavior.

Should a simulation involve a proprietary material, or any other material or material property not already included in the material database, ANSYS CFX users can take advantage of the flexibility of the user environment and the power of the CFX expression language (CEL). CEL allows easy definition of any number of new materials or dependencies of material properties on flow conditions such as pressure, temperature, shear-strain rate and more. Users can enter any algebraic expressions for such custom models directly in the CFX-Pre GUI using the simple CEL syntax, avoiding the need to program separate external routines. It is as straight-forward as writing them down on paper.

View Larger ImagePrediction of wetness dispersion under nonequilibrium conditions for quantification of thermodynamic performance in a low-pressure steam turbineCourtesy Siemens AG.