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JADG December 19, 2003 14:07

Mass balance problem!

I have problem with the mass balance in a pipe with one inlet and two outlets. I am using velocity inlet and Pressure outlet as B.C. But the mass balance doesn't mach, there is a difference of 20% between the mass flow rate at the inlet and the outlets. Any ideas how can I close the mass balance?

Thanks in advance


ap December 20, 2003 07:13

Re: Mass balance problem!
You could try reducing the accepted residuals for convergence of the continuity equation.

Hi :)


Venkatesh December 21, 2003 07:41

Re: Mass balance problem!
I hope you must be using the segregated solver. Just plot the contours of Mass Balance and you can find where the mass balance residuals are high. Check the quality of grid at that location. If you feel the quality is OK then reduce the convergence limit.

JADG December 21, 2003 15:33

Re: Mass balance problem!
Thank you guys I will reduce the residual limits.


Sijal Ahmed December 27, 2003 11:40

Re: Mass balance problem!
set the target mass flow rate by the mass-flow-rate-settings text command


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