Material Property
Material properties are volume conditions in the Flow module that refer to selected volumes.
The material properties appear in the Properties panel when you select a fluid domain under Domains in the Flow Analysis Tree.
Density
Density provides options for setting the value of the density (kg/m3) of the material in a given volume. You can specify the density for a selected volume under the Common module in the Properties panel.
You can specify density as a constant value using the following options:
Constant Density
Ideal Gas Law
Isentropic Gas Law
Compressible Liquid
Viscosity
The viscosity for Newtonian and nonNewtonian fluids is specified in flow models.
Newtonian fluids
NonNewtonian fluids
Herschel-Bulkley Model—Requires specification of four parameters: Yield Stress, Critical Shear Rate, Power Law Index, and Consistency Index.
Bingham Models—Requires specification of three parameters: Yield Stress, Critical Shear Rate, and Bingham Viscosity.
User Defined Function (NonNewtonian)—Requires specification of three parameters: Stress Strain Curve, Minimum Viscosity, Maximum Viscosity. The user defined function uses an arbitrary function between stress and shear rate, such as stress = f(shear rate).
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The user-defined feature is used to fit any arbitrary function of stress and shear rate for NonNewtonian Fluids. For example, the use-defined feature imports experimental measurements from the measurements directly as an input and without simplifications or curve fitting for the Herschel-Bulkley Model.