Injection in spray dryer
 

Hi all,
I have a problem with udf in injection which I really need your help. In my program, I improved mass transfer equation in DPM_HEAT_MASS
After I run my program around 10 repeated steps, it stops and appears alarm as following:
510 3.8538e-05 1.0783e-03 1.0515e-03 1.0933e-03 9.5722e-07 2.0280e-03 6.5532e-04 4.5644e-02 0:43:28 90

reversed flow in 55 faces on pressure-outlet 10015.
# Divergence detected in AMG solver: x-momentum -> Increasing relaxation sweeps!

Error: Divergence detected in AMG solver: x-momentum
I tried to decrease relaxation factor but it was not effective!
Do you have any experience in this case, please help me.
Thank you a lot and best regards,
Tran Hang