Mechanical APDL Basic Analysis Guide - Ansys

Chapter 1: Getting Started with ANSYS
1.1.1.2. Defining an Analysis Title
The /TITLE command (Utility Menu> File> Change Title), defines a title for the analysis. ANSYS includes
the title on all graphics displays and on the solution output. You can issue the /STITLE command to add
subtitles; these will appear in the output, but not in graphics displays.
1.1.1.3. Defining Units
The ANSYS program does not assume a system of units for your analysis. Except in magnetic field analyses,
you can use any system of units so long as you make sure that you use that system for all the data you
enter. (Units must be consistent for all input data.)
For micro-electromechanical systems (MEMS), where dimensions are on the order of microns, see the conversion
factors in System of Units in the Coupled-Field Analysis Guide.
Using the /UNITS command, you can set a marker in the ANSYS database indicating the system of units
that you are using. This command does not convert data from one system of units to another; it simply serves
as a record for subsequent reviews of the analysis.
1.1.2. Defining Element Types
The ANSYS element library contains more than 150 different element types. Each element type has a unique
number and a prefix that identifies the element category: PLANE182, SOLID185, BEAM188, ELBOW290, and
so on. The following element categories are available:
BEAM
CIRCUit
COMBINation
CONTACt
FLUID
HF (High Frequency)
HYPERelastic
INFINite
INTERface
LINK
MASS
MATRIX
The element type determines, among other things:
MESH
Multi-Point Constraint
PIPE
PLANE
PRETS (Pretension)
SHELL
SOLID
SOURCe
SURFace
TARGEt
TRANSducer
USER
VISCOelastic (or viscoplastic)
• The degree-of-freedom set (which in turn implies the discipline - structural, thermal, magnetic, electric,
quadrilateral, brick, etc.)
• Whether the element lies in 2-D or 3-D space.
BEAM188, for example, has six structural degrees of freedom (UX, UY, UZ, ROTX, ROTY, ROTZ), is a line element,
and can be modeled in 3-D space. PLANE77 has a thermal degree of freedom (TEMP), is an 8-node quadrilateral
element, and can be modeled only in 2-D space.
You must be in PREP7, the general preprocessor, to define element types. To do so, you use the ET family
of commands (ET, ETCHG, etc.) or their GUI path equivalents; see the Command Reference for details. You
define the element type by name and give the element a type reference number. For example, the commands
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