Aexp#

Aexp = CONSTANT <float> []

Description / Usage#

This card is used to specify the model for the Aexp parameter of the CARREAU,BINGHAM, CARREAU_WLF and CARREAU_SUSPENSION model options of the Liquid Constitutive Equation card. Definitions of the input parameters are as follows:

CONSTANT

Name of the model for Aexp.

  • <float> - the value of the a exponent in the liquid constitutive models; also, a dimensionless parameter that describes the transition between the low-rate and the power-law region for the Carreau model (see Bird, et. al., 1987).

LEVEL_SET

Name of the model for level-set dependent Aexp parameter. Allows for this parameter level to be a function of the level-set field. Specifically used for changing the Aexp parameter from one constant value on the negative side of the interface to another constant value on the positive side. The model requires three floats:

  • <float1> - the value of Aexp parameter in the negative regions of the level set function.

  • <float2> - the value of Aexp parramete in the positive regioons of the level-set function.

  • <float3> Length scale over which the transition occurs. If this parameter is set to zero, it will default to one-half the Level-Set Length Scale value specified.

Examples#

The following is a sample card that sets Aexp to 3.0:

Aexp = CONSTANT 3.0

Technical Discussion#

See Description/Usage for Liquid Constitutive Equation card.

References#

Bird, R. B., Armstrong, R. C., and Hassager, O. 1987. Dynamics of Polymeric Liquids, 2nd ed., Wiley, New York, Vol. 1.