Mechanical APDL Basic Analysis Guide - Ansys

2. Define the convection boundary condition as a function.
Select Utility Menu> Parameters> Functions> Define/Edit to bring up the function editor. The
function boundary condition being applied is a multivalued function, its final value being dependent
on the X location in the domain. In the Function Editor dialog box, click on the radio button for
“Multivalued function based on regime variable” and type xloc as the name of the regime variable in
the text entry box. The name xloc appears as the name of the regime variable. To define xloc, select
“X” from the drop down box on the lower half of the dialog box. Your dialog box should look like this:
3. Define the equations for the heat transfer coefficient in the two regimes. Click on the Regime 1 tab.
Under this tab, you will define the equation for the first regime, 1 ≤ X ≤ 5. Type “1” and “5” in the
Regime 1 Limits text entry boxes.
4. For the sake of convenience, define those expressions in the equations that you will use more than
once or that are part of a very long equation, and store them in memory.
In this example, expressions for the Reynold's number and Prandtl number are used repeatedly in both
equations. They are good examples of expressions that can be stored and used throughout the function
editor, in all regimes.
To store the Reynold's number, fill in the Result box as shown below. Select the primary variables
DENS, X, and VISC (shown in {brackets}) from the drop down list on the lower half of the dialog box.
Use the keypad to insert the math functions such as * and /. Your dialog box should look like this:
Click on STO, then on M0 on the number pad to store the expression in memory location 0.
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3.5. Function Tool Example
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