Couple of questions.
I am keeping the shock constant and running transient analyses at increasing voltage levels to determine pull in.
I think by definition a
shock cannot be constant (it is a stepped load), so I'm not sure what your thinking is on this.
Is there a way to exit the run completely (get all the way back to BEGIN) when the first pull-in occurs so that I can extract the voltage at which this occurs?
Why do you need to go to the BEGIN level? This sounds very much like a non-linear buckling analysis which we mechies carry out. If this is the case, it should be
exactly the same procedure.
[ul]
[li]Run your transient analysis until non-convergence occurs (make sure you save all of the results for each substep using OUTRES,ALL,ALL).[/li]
[li]When the analysis fails to converge, ANSYS will create a results file with the set number 999999. You'll then need to go into the time-history postprocessor (/post26) and examine your results.[/li]
[li]Review the voltage-deflection curve in the /post26 at the point in your model where you expect pull-in to occur. Be aware that an unconverged solution does not necessarily mean that the structure has reached its maximum load![/li]
[li]The curve will have a characteristic shape, something like a function x
0.5. On this curve, the pull-in voltage should be the last but one result (the last result will be the unconverged solution and will be meaningless).[/li]
[/ul]
Let me know how you get on with it.
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