Hello Friends,

I would like to know a mathematical and/or physical reasons for "pressure spikes" occuring in CFD simulations. I have one simulation case which exhibits this nice pressure spikes behavior(got oppor to learn the reason []).

Let us consider a case with moving boundary zone(cylinder with valve). I am imposing jerking motion BC to the valve. velocity is constant for every two simulation timestep(0-1-2s=> 3m/s, 2-3-4=>5m/s, 4-5-6=>2.5m/s ...). This BC gives me pressure spikes. I have tested many cases with jerking motion and successfully got Pressure Spikes.

Would you explain (or) give me a pointer about P-S cause?. I will be very thankful for this help.

Regards,

Mubassh

Take a look at this

http://dissertations.ub.rug.nl/FILES...eefsman/c2.pdf

on page 76 there's a possible explanation to your question.

Regards

Renato.