simulation of a rotary positive displacement pump
 

Hi guys,

I am facing a problem with my simulation which I was hoping that someone can advise me about.

Long story short: the fluid flows from outlets to inlets instead.

My rotary positive displacement pump has the same mechanism used by the wankel engine. The fluid I am using in this simulation is engine oil as this pump is meant for pumping engine oil.

What I did in FLUENT is I gave my inlets and inlets a boundary condition of 1.5bars at the inlet and 1.8 bars at the outlets. Because I am expecting the actual pump prototype in my lab increases the pressure of the engine oil running through it by 0.3bars.

However, the pressure boundary conditions instead made the engine oil flow from the outlets to the inlets (from a region of higher pressure to a region of lower pressure).

So this simulation doesnt depict how the rotary mechanism increases the pressure of the fluid but rather how the fluid flows naturally from a region of higher pressure to a region of lower pressure despite the presence of the rotor.

So I was hoping someone can enlighten me about this issue.

Thank you very much in advance!