Hello everyone,
I’m trying to optimize a sandwich structure consisting of aluminium face sheets and an aluminium honeycomb core.
As a test case, I’m using a simply supported beam under a pressure load. The overall thickness of the beam should remain constant, while only the thicknesses of the face sheets and the core are allowed to vary.
My objective is to minimize compliance, and as a constraint I set a maximum displacement at the midspan of the beam.
The design variables are the thicknesses of the face sheets. I used a DVPREL2 card linked to a DEQATN equation to keep the total beam thickness constant.
When I run the optimization, the thicknesses of all three components start to change as expected, and the overall thickness stays constant. However, after a few iterations, the solver stops with the message:
“INFEASIBLE DESIGN (AT LEAST ONE CONSTRAINT VIOLATED)”.
The displacement constraint is not reached, and the optimization terminates early.
I already tried changing move limits and starting with different initial values, but this has no effect.
Any help would be apreciated!
Thanks in advance!
