Mechanical APDL Basic Analysis Guide

numbers) appear in different colors so that you can more easily verify the equation you are entering.
You can also graph or list the equation using the GRAPH/LIST button in the Function Editor dialog
box; see Graphing a Function (p. 90) for more information about this feature.

Ensuring the Validity of Your Equation

The Function Editor does not validate the equation construction. (ANSYS generat es an error message
if you enter an inappropriate equation construction.) You must also ensure the mathematical validity
of any equation.

Hint: A common error is a divide-by-zero scenario. Another common problem is a neg-

ative primary variable; in such a case, multiply the primary variable by -1.

Saving and Retrieving Your Equation

If you intend to use an equation or part of an equation later in the function (such as in another regime),
click the STO button to store it.The numbers on the keypad change to a series of memory buffers.
Click one of them to store the equation in that memory buffer.Example:To store your equation in the
Memory1 buffer, click STO and then M1.)

To retrieve a stored equation, click INV and then INS MEM, followed by the appropriate memory button.
The contents of that memory buffer are then displayed in the equation box. You can also recall an ab-
breviated form of the contents by clicking RCL. If you pause the cursor over a memory button, a tool
tip displays the contents of that memory buffer.

3.2.1.1. Selecting Primary Variables in the Function Editor

You can select from among the available primary variables in the Function Editor's drop-down list.
Primary variables marked with an asterisk (*) are also available for tabular boundary conditions (BCs).
The remaining primary variables are appropriate for use with function BCs only.

• Time* (TIME)


• X location* (X) in local global coordinates


• Y location* (Y ) in local global coordinates


• Z location* (Z) in local global coordinates

(coordinate system applicability is determined by the *DIM command)

• Temperature* ( TEMP degree of freedom)


• Fluid temperature (TFLUID) (computed fluid temperature in FLUID116 elements for SURF151 or
  SURF152 elements)


• Velocity* (VELOCITY) (magnitude of the Velocity degrees of freedom or the computed fluid velocity
  in FLUID116 elements)


• Applied surface pressure* (PRES)


• Tsurf* (TS) (element surface temperature for SURF151 or SURF152 elements)


• Density (ρ) (material property DENS)

Release 15.0 - © SAS IP, Inc. All rights reserved. - Contains proprietary and confidential information

Using the Function Editor