| Axial piston pump is developing in the direction of high pressure,high power and high reliability.The key to achieve this series of goals is to design reasonably the friction pairs in the piston pump so as to form a suitable oil film so as to improve the working efficiency and service life of the piston pump.Valve pair is one of the most important friction pairs in axial piston pump,and it is also the most easily worn parts.Plunger to realize the conversion of high and low pressure cavity,high pressure piston pump is easy to produce cavitation phenomenon.If the bubble burst is located on the surface of the orifice plate,cavitation damage may occur to the orifice plate.Therefore,it is of great significance to study the characteristics of flow field and anti-cavitation flow plate.In this paper,with the aid of Shanxi science and technology major project-high bearing high wear resistant flow disc material and technology development(MC2015-01)and the project of National Natural Science Foundation Youth Science Foundation(51605320),this paper takes a piston pump flat flow port plate as the research object.Based on the method of CFD numerical calculation and theoretical analysis,the flow field model of piston pump is established.The characteristics of pressure distribution in sealing zone of piston pump distribution pair and the effect of oil viscosity on velocity field distribution and leakage loss of distribution pair are studied.And the effect of oil film thickness on the reverse thrust of oil film.(1)Pressure distribution characteristics of the sealing belt of the port plate.The pressure distribution of the inner and outer sealing belts of the valve plate is approximately linear.The pressure at the edge of the seal belt is the lowest,and the higher the pressure is near the seal belt,the highest pressure of the seal belt is the working pressure of the piston pump;with the increase of the working pressure,the pressure gradient of the seal belt becomes larger.(2)Effect of oil viscosity on velocity distribution and leakage loss of the port plate.Under the same oil viscosity,the leakage rate of seal belt increaseswith the increase of outlet pressure,and the leakage loss increases with the increase of outlet pressure,while the leakage rate of seal belt decreases with the increase of oil viscosity under the same working pressure,and the leakage rate of seal belt increases with the increase of outlet pressure,and the leakage rate decreases with the increase of oil viscosity.The leakage loss decreases with the increase of oil viscosity,and the effect of pressure on the sealing speed decreases with the increase of oil viscosity.(3)Effect of Oil Film thickness on reverse thrust of Oil Film.Under the same working pressure and different oil film thickness,the reverse thrust value of oil film is different.With the increase of oil film thickness,the area of high pressure area of oil film becomes smaller,and the reverse thrust of oil film decreases.(4)Effect of depth angle of triangular groove on jet angle.The jet angle increases with the increase of the depth angle in the range of 5 °to 10 °,while the jet angle does not change with the increase of the depth angle in the range of 10 °to 13 °.(5)Anti-cavitation structure design.Through the analysis of the flow field of the cavitation resistant structure,the differences between the cavitation resistant structure and the existing structure are discussed from three aspects of pressure,velocity and jet angle.The results show that the cavitation resistant structure can effectively increase the jet angle of "backflow" oil,which is helpful to reduce the damage effect of cavitation erosion on the orifice plate. |
PDF Full Text Request