Dynamic characterization and structural parameter optimization of rotary direct-drive electrohydraulic servo valve

For the dynamic response optimization of rotary direct-drive electro-hydraulic pressure servo valve (RDDPV), the structural parameters of the spool damping orifice were investigated using a numerical analysis model and CFD simulation method. Key factors such as the inlet shape, the effect of temperature on the viscosity of hydraulic oil, and the eccentricity error e1 between the axis of the cylindrical bore and the axis of the spool are focused on, and the optimized design interval of the spool structure is proposed. The results show that optimizing the inlet shape can effectively reduce the turbulent kinetic energy, pressure loss, and damping force and improve the dynamic performance. Increasing temperature will reduce the hydraulic fluid viscosity and increase the turbulence intensity and damping force, so it is necessary to effectively control the temperature. Controlling the eccentricity error e1 in the range of 10–20 μm can significantly improve the peak time of the step response and the response speed. This study provides an important reference for the structural design and performance optimization of RDDPV, which meets the dynamic response requirements in practical applications.