HyperXtrude allows you to input fluid properties and boundary conditions as a function of space. This is done using the FUNCTIONS block. The function can be an expression, a one-dimensional table, or a two-dimensional table.

 

Syntax

BEGIN FUNCTIONS

 Function_Type Variable { Expression/Data }

END

 

Comments

Valid entries for Function_Type are: CONSTANT, TABLE1, and EXPRESSION. Variable is the name of the data field represented as a function. Expression denotes algebraic expression used to compute the variable. Data denotes the tabular data used to compute the variable. Examples of syntax for the function types are provided below.

 

TABLE1 Example

This example illustrates the definition of viscosity (kg/m-sec) as a function of temperature (K).

 

BEGIN FUNCTION

TABLE1 Viscosity_vs_Temp {

 250.0 1.606E-05

 300.0 1.853E-05

 350.0 2.081E-05

 400.0 2.294E-05

 450.0 2.493E-05

 500.0 3.682E-05 }

END

 

EXPRESSION Example

This example illustrates the definition of inlet velocity as a function of coordinates (x, y, z) and time (t). The input variables to the expression are (x,y,z,t).

 

BEGIN FUNCTION

# (Parabolic velocity at inlet)

 EXPRESSION XVelocity "{x y z t} {expr 240*($y)*(1.0 - ($y))}"

END

 

BEGIN FUNCTION

# (Time dependent velocity)

 EXPRESSION XVelocity "{x y z t} {expr 20.00*(cos(3.141592654*($t)))}"

END

 

 

See also

The Gridfile (*.grf)