Numerical simulation on an aero-engine vane pump

The internal flow field of an aero-engine vane pump was simulated with the function of the secondary development of computational fluid dynamics software Star-cd. The impacts of incorporating/neglecting the cavitation model on simulation results, the gap size between the tip of vane and stator of vane pump were analysized. The sizes and positions of cavitation in vane pump were predicated under different working conditions. The simulation results demonstrate that cavitation is generated, developed and collapsed during the rotation of rotor, which leads to accumulation and release of the mass of oil, correspondingly to a reduced and increased area of cavitation respectively, and the transient volume flow rate of inlet is stable while that of outlet fluctuates significantly. The simulation results show the difference between cycle averaged valume flow rate at inlet/outlet and total averaged volume flow rate is less than 1.5%, and the difference between total averaged volume flow rate and averaged volume flow rate obtained from the experiment of the vane pump is less than 3%. The simulation results also demonstrate that expanding the gap between the tip of vane and the stator results in a decrease of the average volume flow rate of the vane pump and an increase in the leakage, which can be seen from that the averaged volume flow rate of the gap size equaling 0.07mm is reduced 3.1% relative to that of the gap size equaling 0.02mm. It is estimated that if the inlet duct is designed to face the suction port, the flow resistance and the area of cavitation can be reduced.