Mechanical APDL Basic Analysis Guide - Ansys

Figure 5.3 Examples of Time-Varying Loads
Suppose that you have a set of time-varying loads such as the ones shown above. There are three load
functions, so you need to define three array parameters. All three array parameters must be of type TABLE.
The force function has five points, so it needs a 5 x 1 array; the pressure function needs a 6 x 1 array; and
the temperature function needs a 2 x 1 array. Notice that all three arrays are one-dimensional. The load
values are entered in column 1 and the time values are entered in column zero. (The zeroth column and
zeroth row, which normally contain index numbers, must be changed and filled with a monotonically increasing
set of numbers if you define the array parameter as a TABLE.)
To define the three array parameters, you first need to declare their type and dimensions. To do so, use
either of the following:
Command(s): *DIM
GUI: Utility Menu> Parameters> Array Parameters> Define/Edit
For example:
*DIM,FORCE,TABLE,5,1
*DIM,PRESSURE,TABLE,6,1
*DIM,TEMP,TABLE,2,1
You can now use either the array parameter editor (Utility Menu> Parameters> Array Parameters>
Define/Edit) or a set of "=" commands to fill these arrays. The latter method is shown below.
FORCE(1,1)=100,2000,2000,800,100 ! Force values in column 1
FORCE(1,0)=0,21.5,50.9,98.7,112 ! Corresponding time values in column 0
FORCE(0,1)=1 ! Zeroth row
PRESSURE(1,1)=1000,1000,500,500,1000,1000
PRESSURE(1,0)=0,35,35.8,74.4,76,112
PRESSURE(0,1)=1
TEMP(1,1)=800,75
TEMP(1,0)=0,112
TEMP(0,1)=1
You have now defined the load histories. To apply these loads and obtain the solution, you need to construct
a do-loop (using the commands *DO and *ENDDO) such as the one shown below:
TM_START=1E-6 ! Starting time (must be > 0)
TM_END=112 ! Ending time of the transient
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5.7.3. Using the Array Parameter Method
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