Research on Pressure-Flow Characteristics of Pilot Stage in Jet Pipe Servo-Valve

Jet pipe servo-valves are widely used in high-precision servo control systems. However, the accuracy of pressure-flow characteristic equations relevant to its pilot stage needs to be improved. In contrast to the traditional analytical approach using the orifice equation, the article investigates the pressure and flow characteristics of the pilot stage based on the impact jet principle. Taking the pre-stage of a certain type of jet pipe servo-valve as an example, the flow field is simulated using ANASYS software. By comparing the simulation data with the calculation results, the pressure characteristic model is basically consistent with the simulation data, and the relative error is less than 2.3%. The error between the revised flow characteristic model and the simulation result is small, and the maximum deviation is less than 0.0022 L/min. Finally, to verify the applicability of the model to other specifications, the experimental data in the literature are compared with the theoretical calculation results, the maximum relative error of pressure characteristics is 2.19%, and the relative error of flow characteristics is less than 5.34%.