Ai Chao

Research on the effect law of damping orifice on flow characteristics of proportional multi-way valve

In order to improve flow stability of proportional multi-way valve, a mathematical model of main valve combined with pilot valve was built based on the Power Bond Graph theory, static and dynamic characteristics was obtained under chatter signal by using digital simulation procedure and an experimental table was put up to verify it. The results of simulation and experiment show that the flow fluctuation amplitude of proportional multi-way valve decreases with the increase of liquid resistance of damping orifice, but decreasing range is reduced. Besides, the flow rate response time of the valve increases with the increase of liquid resistance. The research verifies that reducing damping orifice can improve flow stability as well as realize the stability of actuator movement under satisfying the flow rate response rapidity.

Research on the factors that affect the throttling mouth flow coefficient of spool valve

This paper establishes the CFD (Computational Fluid Dynamics)model of the Servo valve, and computes the velocity field of internal flow field in the spool valve of the servo valve under the different work pressures, different work temperatures and different opening lengths. By analyzing the flow coefficient of the orifice of the servo spool valve at the different work conditions, we further research the influence rule of the opening of the orifice, the flow direction, the valve ports shape, the valve inlet pressure, and oil temperature on the flow coefficient.

Co-simulation research on fuzzy PID control of the synchronism-balancing system of oil press

The simulation of synchronism-balancing hydraulic system of 20MN free forging oil press was done in this paper. The model of fuzzy controller was established by Matlab. The models of hydraulic system and parameters adjustable PID controller were established by AMESim. Then the technologies of co-simulation were used. Simulation results show that the synchronism-balancing hydraulic system can effectively compensate the synchronous error of moving beam corners which was caused by forging eccentricity. Compared with the traditional PID, parameters self-turning fuzzy PID control system has better robustness.