Combination of frequency response and temperature load

Benjamin_22203

Hello everyone,

I am working on a frequency response case at the moment. In the environment in which the structure is exposed to vibrations, there is also an increased temperature. Therefore, I would like to put a linear static load step in front of it, where the structure is preloaded by the temperature and put the frequency response load step on top of it. Is this possible with Hypermesh/Opstistruct?

Thanks a lot

Benjamin

Gildas_GUILLY

Hello Benjamin,
You can perform preloaded frequency response analysis with OptiStruct by using the STATSUB(PRELOAD) parameter in the definition of your frequency response analysis.
The process is :
1 - You create your linear static analysis with thermal loading (TEMP and/or TEMPD loading)
2 - Create your FR loadstep with the dynamic loading (DLOAD)
3 - In the definition of this second subcase, you will find the STATSUB(PRELOAD) parameter. Activate it and point to the static loadstep.

It is important though that you understand what it will do.
Doint so you will consider the effect of static loading on the structure stiffness (like adding tension in a guitar string will change its natural frequency).
But results (like stress) provided by the FR analysis do not include any participation fro static loading, as the result is complex, so always describing an oscillating result around 0.

Gildas