Defining the pulsation source in Puls software for centrifugal compressors ?

Hello Everybody,   

One of my company Customer want us to provide piping pulsation analysis for gas compressor station where theoretically pulsation sources are two centrifugal compressors. I know that Puls software is not designed for piping pulsation with centrifugal compressors. Centrifugal compressors particularly in these times should not be considered as pulsation pressure source, however it has been assumed and defined by the Customer that these pulsation sources should not exceed 10% of maximum pulsation value peak to peak based on API 618 in Puls software for given rpm of compressors? 

1.Based on requirement of 10% how exactly should I define the pulsation source to perform pressure and force simulation vs frequency in Puls? Would 10% of the pressure pulsation curve based on API 618 be my input, and having that I should calculate forces vs frequecy for each node then the harmonics would be imported to Autopipe (harmonics described by damping of ~2%, frequency for the 1-st, 2-nd, and 3-rd harmonics with phases and forces acting in different direction)?    Can I find any example in Bentley resources that could show me practical way of solving problem mentioned above?      

Given data:

Suction side – 4MPa

Discharge side – 6,5MPa

Methane gas flow – 140 thousand m3/h

             

2.   If the piping model in Puls will have less than 400 nodes for both suction and discharge lines it seems to me that option 1 of Puls software be good enough to make pressure and dynamic forces acoustic simulations (with two centrifugal compressors) ? Am I correct thinking so?  

Best Regards

Robert Augustyn