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Sumon March 20, 2002 02:40

Mass balance
 
Hi everyone

I have a problem with the mass balance.

It is multi-phase (three phases) model. There are two inlets.

Inlet1: Only phase 1 Inlet2: Phase 2 and Phase 3 (0.9 and 0.1 volume fraction respectively)

Outlet is as pressure boundary. Ambient conditions and initial guess are set (vol. fraction of phase 2 is almost 1.0).

K-eps turbulence model is used and the inlet boundary conditions are set with proper parameters.

But the mass flow rate through the pressure boundary flactuate with the number of iterations.

It is very difficult to converge 3 orders. At the moment it converge near about 3 orders.

But I don't know why the mass is flactuating through the pressure boundary.

Could any one help me on this regard. Any suggestion or tips will appreciate.

Regards

Sumon

Astrid March 20, 2002 17:41

Re: Mass balance
 
Whatprogram do you use? CFX 5.5, 4.4 or Tascflow?

Astrid

Sumon March 20, 2002 19:27

Re: Mass balance
 
Hi Astrid

I am using CFX 4.3 for multi phase flow at the moment. Mass should be balance in inlets and pressure boundaries. But I have still problems.

Regards

Sumon


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