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CFX Reverse flow problem even if open boundary used

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Old   December 5, 2013, 06:33
Default CFX Reverse flow problem even if open boundary used
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Rohit Adhav IIT Madras
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I am Rohit

I am performing simulation of water flowing through centrifugal pump impeller (only impeller is considered) .
i am getting flow rate = zero and in report reverse flow is observed. i.e i am getting completely wrang results.
even if i use open boundary condition at outlet.
same problem appears for 38000 elements, 70000 elements and 1 lac elements of mesh. (structured mesh i created using turbogrid)

can anybody help me in this regard.?
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Old   December 5, 2013, 07:35
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What happens if you move your fluid domain boundaries further away from the impeller? See // Modeling Guide // 2. Boundary Condition Modeling // 2.3. Using Boundary Conditions // 2.3.3. Using Inlets, Outlets and Openings Figs 2.1 to 2.3 in the CFX v14.5 Help.
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Old   December 5, 2013, 17:01
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Glenn Horrocks
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Have you checked you are at the right operating point? That means the flow rate and pressures are expected to work for the pump design and RPM. Also, are you sure the impeller is rotating in the correct direction?
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