Hi, I use the sliding mesh and momentum sources term. The command of sliding mesh I used is "mixasi". The command of Sources term is "sormom.f". The problem after running is "sormom.f is activated but not used". I don't what the problem is. I have try many times and I need your help, sincerely. Thank you for your help. Luan

Any help will be great.

It is likely that you haven't turn on the momentum source in PROSTAR. If you use STAR-CD v3.2, in PROSTAR Nav Center, Thermophysical Models=>Sources=>Source Terms, Select Momentum, On and click Apply, write problem file and quit,save.

Just as a curiosity, if you use sliding mesh for the mixer type of flow, normally you don't need momentum source. So what is your source for?

John Thank you very much for your help. I used STAR-CD v3.2. I have turned on the momentum source in PROSTAR as you shown: in PROSTAR Nav Center When I use the sliding mesh only, it can run and have no problem. When I use the momentum source only, it can run and have no problem too. When I use the sliding mesh and momentum source together, it can't run and the running error is as following: "sormom.f is activated but not used". The process I used is as following: 1) file
:system command enter FILES Create a folder 2) Thermophysical models and porperties
:sources
:sources term
:momenturm
n apply and define user coding

But have you modified the sormom.f file? I don't understand...Because if you have activated the momentum source but you haven't modified that file you don't use any momentum source...what is the difference for this last sim where you have activated the sormom.f file by means of "apply and define user code" button and the other first sim???
Look in the ufile directory...