Research on the operation mechanism and stability of marine textured directional valve

Based on the vibration force analysis of the marine electromagnetic directional valve and Newton’s Second Law, the mathematical model of the displacement of the valve rod under vibration excitation state is established. The influence of vibration parameters and viscous damping coefficient on its operation stability is calculated and analyzed. Results show that the vibration stability can be improved by increasing the clearance viscous damping of the directional valve, and the textured surface affecting on the viscous force and flow resistance characteristics. All of these provide a basis for stability optimization. The on-board experiment of marine electromagnetic directional valve in real-time working condition is operated, the performance difference between the textured and untextured valve is analyzed. The results show that the pressure adjustment time and vibration impact amplitude of two kinds of directional valves decrease with the increase of oil supply pressure, and increase with the increase of navigation speed. The standard deviation of flow fluctuation of untextured directional valve increases with the increase of oil supply pressure, while the flow fluctuation of micro-textured directional valve first decreases and then increases. The unique interface characteristics of the micro-textured directional valve make the pressure adjustment time, the standard deviation of flow pulsation, and the vibration impact amplitude of the micro-textured valve smaller than that of the untextured one.