Research On Vibration And Noise Reduction For Water Hydraulic Variable Displacement Vane Pump

Low noise vane-type water hydraulic pump has broad application prospects and market demand in naval vessels and many industrial areas,due to its smooth outlet pressure and flowrate,low vibration noise,compact structure,etc.This paper aims to research on vibration and noise reduction technology for vane-type water hydraulic pump with rated pressure 10 MPa,rated speed 1500r/min and rated displacement 40mL/r,through reducing flow-distribution noise and cam-ring mechanical vibration.The imperfections of existing design theories and methods for silencing groove were analyzed.Then the reverse optimization new theory was proposed.And the technical route of combining theoretical optimization and experimental research was also elaborated.Based on the mathematical model and the new optimization theory,the line-function,index-function and parabola grooves were obtained.The optimization results indicated that their flow impact resistance performance is better than traditional triangular groove and triangular rectangular groove.By establishing the dynamic fluid field model,the cavitation properties of every grooves in the transition zone were simulated.The results of vapor volume fraction and cavitation type showed that the new silencing grooves have better cavitation resistance property.The experiment device to simulate flow-distribution for silencing grooves was designed.Through pressure-flow characteristics experiment,the throttle nonlinear functions were obtained by six-function curve fitting,that provides a reversed basis for the reverse optimization model.To investigate and identify cavitation,the vibration acceleration spectrum,pressure pulsation spectrum and noise spectrum were collected during experiment.The spectrum analysis results and simulation results both proved that the parabola groove has the best vibration and noise reduction properties.So it was selected as the optimal silencing structure.Based on the optimal silencing groove,the force mathematical model of cam-ring vibration was established.Then the fluctuations of the hydraulic radial force and the vane contact force were calculated.Using the residual compression force method,the support structure of the cam-ring was designed.The friction force when the cam-ring moves was analyzed in different pressure.Based on the analysis of cam-ring vibration force,the variable regulator and the damping network structure were designed.And the coupling simulation model of the cam-ring dynamics model and pump fluid model was created.Then the multi-field coupled simulation optimization for the water pump was conducted,using the characteristic parameters of fluid and mechanical noise as optimization objects.The simulation results showed that the cam-ring could quickly response to variable.However,due to the impact of multiple fluctuation force,the cam-ring was always in a floating dynamic balance vibration state,and the amplitude was about 0.123 mm.Compared to the vane-type oil hydraulic pump in related literatures,the water pump in this paper has smaller pressure overshoot,vibration and flowrate pulsation.