A New Type Unloading Groove Design and Simulation for Engine Fuel Gear Pump

The problems of oil trapping in aircraft engines fuel gear pump is related to low pump volumetric efficiency, large flow pulsation, pressure fluctuation, cavitation and other serious hazards. Aiming at this problem, this paper gives a new design method of unloading groove in engine fuel gear pump by establishing the calculation model of trapped oil volume, then the internal flow field of gear pump is modeled and simulated. The results show that the designed new unloading groove can significantly reduce the maximum trapped oil pressure and flow fluctuation rate, and effectively alleviate the problem of oil trapping and cavitation of gear pump.