Hello,
I have been doing an optimization with Optistruct and now I want to do a sensitivity analysis. I optimized the gap between desired and current frequencies of some modes, using this formula:
delta_f = sum[(f_now_1 - f_desired_1)^2+...+(f_now_10 - f_desired_10)^2]
I used the OUTPUT cards to create .slk files for all iterations. I used normal orthotropic material behaviour, so I have 5 design variables and delta_f as the response. What I am looking for is something like "I change variable 1 by 10% and delta_f changes for xx%". If I do this for all 5 variables I will find out which has the most impact on the solution, right? How I understand the .slk file, I can say something like "the new value of variable 1 = 1,1* old_value of variable 1" and then it will calculate the new estimated response and I can see how much it would change.
Is my train of thought correct? If yes, which Iteration would i use for my calculations, since the sensitivities are changing? My guess would be the first iteration, because it usually has the highest change?
I have a mixture of positive and negative sensitivities, so I should use the conservative response?
Do the sensitivities have a specific unit, e.g. in %? Below is the slk file for Iteration 0, how do I interpret a sensitivity of 244 for E_P?
