I am doing a study to see if a dynamic analysis can be done on the compressor discharge header. This header is connected to discharge piping of three compressors. It is outside of the compressor building. The compressor vendor has done acoustic analysis for the compressor piping within the compressor building.

My questions are:

1. The vendor only supplied shaking forces for the piping inside of the compressor building. How can I calculate the shaking force of the header? If I use the harmonic analysis for the header, should I apply the shaking force for each elbow at the same time?

2. How to consider the effects of the vibraion of the compressors and dischrage piping on the header?

Thanks,