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YYY September 18, 2009 03:40

Regenerative pump modelled in FLOEFD pro
I am now simulating the regenerative pump in floefd pro. I used to use EFD to model the centrifugal pump with rotation region.

I use the same manner to do so for the regenerative pump. Since I applied the same blade diameter for both pump types, I acutally know the flow rate range and pressure rise range. But the results in the case of regenerative pump shows the negative pressure rise. I also put the minimal solid thickness and minimal gap distance and the convergence is OK. BC I put the flow by inlet and environment pressure by out let. A solid part covered the pump blade is used as rotation region, two surface faced with the pump surface as stator.

Who can explain why? possible due to the turblence model in EFD?

murat October 3, 2009 06:50

Could you upload solution pic of fan for velocity and pressure?

I think you create outlet pressure 1 atm(101325 Pa) but your model DeltaP is higher than outlet pressure may be it causes negative pressure

You can create outlet pressure 10 bar then solve again it may be solving your problem

And also if the FloEFD calculates did you check the warning monitor? Was it showing a message as Negative Pressure?

YYY October 5, 2009 05:04

Thank you for your reply

Acutally I create outlet pressure 3 bara and the expected dP is around 15000Pa.

I did not see the warning during the calculation. I have contacted with EFD technique support and they told me EFD capacity for this kind of problem is limited. I tried not to use the rotation artifical part but with global rotating and stator wall, but it did not help it.
The pressure and velocity results showed the problem at outlet. I already prolonged the outlet pipe, no useful.

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