Thanks for your helpful and quick reply
I really learn a lot from your comprehensive explanation and thanks again for your patient help.
1. what I mean is exactly clicking No at the slow script dialog.
2. I also ask my academic professor about the amplitude of the 1.4mm, since it is the amplitude of the output but not input, what you had mentioned is very reasonable that 1.4mm input will cause very large deformation, but here comes a question, since with the large deflection turned on, the whole structure will be stiffened, which means the 23mm result from linear frequency response is not accurate. if large deflection is turned on, will it be possible that the 23mm deformation will be reduced to 2mm?
3. The reason why I pick the 20000 data points with 10s is because we are doing a sine sweep from 50 to 220hz and the nonlinear effect happens at around 190hz, therefore I have no choice to shorten the range from 50-210 to 70-110.