Hi all,

I am using MRF model to simulate 3d a centrifugal pump. The flow cab be assumed steady. I have used two reference frames, one is stationary ,and the other is rotation(which include the blades). But the deference between the numerical results & experimental results is about 30%, What's the reason? is it proper for me using the MRF? I would appreciate if anybody can give me advice. Thanks!

Wason

Hi Wason, What are your BC's? How many iterations you have made? Convergence? Which model did you use?

Thank you for your question, What are your BC's? Inlet is velocity Outlet is outflow Rotation Zone is using Ratation flow

How many iterations you have made? About 4000 iterations

Convergence? yes, Which model did you use? Segregated , SimpleC & Simpler

Thanks again

Wason July 7

Hi Wason, I prefer to use pressure inlet and pressure outlet equal to zero if I don't know the flow rate of the turbomachine and I use RNG k-e model. Under these conditions, you should find out flow rate almost equal to the experimental results. On the other hand presure head of the turbomachine depends on your geometry. To make better discussion about pressure head, I have to see your geometry.

Ahmet