The Research On Poppet Valve Vibration Based On Corrected Hydrodynamic Force

Hydraulic poppet valve become an important fundamental component in hydraulic transmission and control system for the reason of simple structure, good sealing property and opening without " dead zone". It was widely used for controlling pressure, flow rate and direction of the hydraulic system in cartridge valve, relief valve and check valve. However, the poppet valve vibration problem in engineering brings many problems such as loss of control accuracy, noise pollution even the valves function failure, these problems restrict the application of poppet valve. With the development and widely used of cartridge technology, It’s proposed more accurate requirements for poppet valves. Therefore it is important for researching the poppet valve vibration problem in engineering application.Because of the poppet valve are used in different areas, the reason of the poppet valve vibration are different. The paper analysis the reason of the cartridge valve and relief valve which are widely used in hydraulic system vibration based on the corrected hydrodynamic force system vibration model.This thesis consists of five parts:(1) Making CFD steady-state computing under different valve lifts and different pressures of the three cartridge valves. Pointing out that the traditional steady-state flow force express was not accurate based on CFD analysis results. Making CFD transient-state computing of the three cartridge valves, Getting the transient-state flow force express’s important parameter the length of damping "L".(2)Building the system dynamic simulation model in SIMULINK based on the corrected hydrodynamic force, in the simulation model the steady-state flow force and transient-state flow force which offered by CFD computing results. It realized that the hydraulic flow force was combined with the valve port structure parameters. Analysis the vibration characteristics of the three cartridge valves, Getting that the number1valve structure is more easy to be steady than the others and the transient-state flow force is the main reason of the cartridge valves vibration.(3) Making experiments research of the cartridge valves, verified the exactness of the simulation model and simulation conclusion.(4) Analysis the cartridge valve structure parameter effects to the poppet valve vibration, the results show that design the valve seat diameter to make the valve and valve seat space at proper value, make the valve seat angle closely to the valve angle, the cartridge would be steady.(5) Design the piloted relief valve based on the analysis results, discussing the effect of external factors such as air content in oil, oil temperature and the structure of relief valve to the piloted relief valve vibration. It shows that reduce the air content in oil, reduce the oil temperature and adjust the relief valve structure parameters would be contribute to the pilot valve’s stability.