Design Improvement of Unloading Groove Structure for Fluid Dynamic Performance of External Gear Pumps

Abstract

External gear pump is a commonly used pump in hydraulic transmission system, and its dynamical performance directly affects the working stability and efficiency of the system. The tooth backlash is one of the important factors influencing the flow pulsation of the external gear pump, and the design of the unloading groove is an important measure to alleviate the oil trapping phenomenon, which can effectively alleviate the pressure of the oil trapping area, and will also have a certain effect on the flow pulsation and pressure pulsation, and the effect of different kinds of unloading grooves is also different. In this work, the software PumpLinx is applied to simulate the fluid dynamics of the gear pump equipped with a special-shaped unloading groove in the presence or absence of tooth backlash. The optimal design of the unloading groove is carried out to improve the performance of the gear pump to a certain extent. The results of this study have important reference value for the dynamic design and optimization of external gear pumps.