We noticed your questions in the Ansys Learning channel on YouTube. You asked a few questions. Let's see if this helps.
To perform a pre-stressed harmonic analysis you can do a pre-stressed modal followed by harmonic. This video details the pre-stress modal method.
If you are going to use the full method, you can connect static structural to harmonic as shown below and this will be a pre-stress harmonic using the full method.
Now you also asked about MSUP (Mode Superposition Harmonic) vs Full. It is discussed in this course.
There are advantages to both methods, but in general, here are some key points;
-Solve for the modes once, then the solution of the harmonic equations is quick and you can experiment with different loads without having to rerun the modal analysis. In full you will have to resolve all the equations and this can take increased time
-You can use modal damping where the damping ratio is a function of frequency, and this can help in correlating simulation with test
-MSUP harmonic solves fewer uncoupled equations
-If you extract too few modes, you will get inaccurate results, so take care that sufficient modes are extracted
Finally, you had asked about damping and you will also find a newly release damping course on the platform, and in that course we discuss some general guidlines on damping values, but also, how to experimentally compute damping ratios.
I hope this helps. Please let us know. Thank you.