Coupled Analysis

[harshn]

Hi,

I am trying to do a thermo-mechanical coupled analysis, in the mechanical part I wish to do a modal analysis.

I have defined the thermal and mechanical parameters and compatible element. First I apply thermal boundary condition and solve for temperature distribution and the write the PHYSICS environment. Then I use the following to enter the modal analysis type
/solu !Re-enter the solution phase
ANTYPE,MODAL ! Choose modal analysis type

then I read the struct environment
physics,read,struct ! Read in the struct environment

after this I read the thermal load by
ldread,temp,,,,,,rth ! Apply loads derived from thermal environment

I am not able to see any apperent change in modal values even if I am changing the temperature boundary condition by great amount. It seems I have not coupled it properly, can someone throw some light on this

Thanks and Regards

 

[harshn]

I tried the following and it seemed to work, can any one confirm if my approach is right?

After doing the thermal analysis I proceeded to static anlysis with Pressure effects turned on and thermal load read using LDREAD... once the static solution was done I re-entered the solution mode and executed the modal analysis.

In short after thermal distribution I tried to convert it to a PRE-STRESS problem.

 

[cbrn]

Hi,
yes, your last post seems to contain the right way to proceed: you won't see anything in the modal analysis unless the "Prestress Effects" are not turned on, and in order to do so, the modal analysis must be preceded by a structural one with "Calculate Prestress Effects" turned on as well.

Regards