Frequency Response Optimization Optistruct
Hi, I have been trying to optimize the frequency of a basic plate with a hole, the plate is fixed on two ends for all 6 DOF's and a normal modal analysis is being run. The Dimensions for the plate are 550 mm x 550 mm with a thickness of 10 mm. E = 70000, p = 0.33, density = 2.75e-6, wtmass conversion of .001.
The first mode is coming at 204 Hz.
Now after I add my design variable with the default base thickness in the optimization>topology menu. I proceed to add Volume fraction, and Frequency as my responses.
As my aim is to constrain the frequency I add a lower bound of 300 with the objective of minimizing frequency.
now after i run the optimization on obstructionist and attach the s1.h3d file to see what the optimized results frequency are they are lower then the original not optimized plate at 195 Hz.
I do not understand what I am doing wrong here. Any help would be greatly appreciated.
Thank You.