Abstract: Aiming at the phenomenon that excessive hydraulic force caused the spool reversing lag or even stuck in the process of direct-acting proportional valve spool reversing, a hydraulic force compensation method based on valve spool structure optimization was proposed. Firstly, the three-dimensional modeling software was used to model the structure of the direct-acting proportional valve. Then, by combining theoretical deduction with computational fluid dynamics(CFD)simulation, the variation law of the steady hydraulic force with the valve opening and pressure difference was analyzed. Finally, according to the theoretical expression of the hydrodynamic momentum theorem, a spool structure with hydrodynamic compensation function was proposed, and the influence of the optimized spool structure on the hydrodynamic and flow characteristics was analyzed. The results show that the hydraulic force of the spool can be reduced more obviously by using the optimized spool structure in the high pressure and large flow environment. According to the hydrodynamic simulation results of the whole basin, the maximum compensation effect of hydraulic power can reach 45%, which effectively reduces the influence of hydraulic force on valve characteristics,and has a positive effect on improving the dynamic response of the direct-acting proportional valve.

Key words:  direct acting proportional valve; hydrodynamic compensation; steady-state fluid power; valve spool structure optimization

BAI Jun, ZHAO Bin, HAO Yun-xiao, et al. Hydrodynamic compensation method of proportional valve based on valve spool structure optimization［J］.Journal of Mechanical & Electrical Engineering, 2021,38(11):1444-1450.