| As a kind of oil pump,gear pump is widely used in vehicle engine lubrication system.But because the pressure pulsation of the flow pressure of the gear pump is huge,it will cause the vibration of the lower level components at the same time,which will aggravate the wear of the components and reduce the service life.Therefore,in this paper,the problem of the large flow pulsation of the gear pump is studied.By changing the gear tooth shape and rationally configuring the gear parameters,the flow pressure pulsation of the gear pump can be reduced.In this paper,the gear pump is designed based on circular-arc tooth profile to reduce the flow pressure pulsation of the gear pump.Based on the mathematical method,the mathematical model of "arc-involute-arc" tooth profile was established and the feasibility of its meshing was verified.The instantaneous flow model of the circular-arc gear was established by the "swept area " method,and the instantaneous flow quality was analyzed.Taking the involute gear pump as the reference standard,the tooth profile parameters were optimized.It was found that the circular-arc tooth profile can effectively reduce the flow pulsation without reducing the instantaneous flow rate.By analyzing the leakage of the gear pump,the links of the pressure and leakage of the tooth chamber are established.Based on this,a dynamic simulation method to simplify the pressure of the tooth cavity is proposed by Matlab and Fluent.We also verified its feasibility to reduce the workload of simulation and improve research efficiency.During the simulation,it was found that the pressure of the tooth cavity pressure suddenly jumped along with the rotation of the gear.Therefore,the triangular vibration damping groove was set on the floating side to realize the pre-boost of the tooth cavity,so that the pressure of the tooth cavity was abruptly snapped off and the cavity pressure rises steadily.In this paper,the dynamic simulation of the two-dimensional flow field of the circular arc gear pump is carried out by using the Fluent simulation software,and the change of the flow field of the gear pump during the rotation process is explored.The pressure of the gear pump and the velocity distribution of the oil in the operation process are analyzed,and the results are compared with the simplified dynamic simulation model.The variation trend of pressure in the cavity is almost the same,which verifies the correctness of the simplified simulation model,and analyzes the influence of cavitation on the flow pulsation of the gear pump outlet.Through the modeling of the tooth profile and the instantaneous flow analysis,it is found that the circular-arc tooth profile can effectively reduce the flow pulsation in theory;based on the theoretical analysis of the leakage of the gear pump,a simplified dynamic simulation method is proposed,and its feasibility were verified.The two-dimensional flow field of the gear pump was analyzed by Fluent software,which verified the partial correctness of the simplified dynamic simulation model.In this way the design of the circular-arc tooth profile gear pump was made and the three-dimensional gear pump modal was obtained. |
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