Study On Experimental Method Of The Pilot Relief Valve Opening And Closing Characteristics

In this paper, the pilot relief valve opening and closing characteristics of the experimental method and process were studied. Firstly, the pilot relief valve static characteristic equations were improved, and the algorithms to solve the equations were studied, then the genetic algorithm was used to solve the problem, at last, the pilot relief valve opening and closing characteristics experiment was simulated on the computer.In order to the pilot relief valve opening and closing the opening characteristic curve and closed curve "closed", in the pilot relief valve static characteristic equations, the friction forces of the force balance equations about the pilot valve and the main valve were replaced with integrated damping forces, and the pseudo-velocity items of the integrated damping forces were analyzed, the corresponding model was given.The genetic algorithm program based on the basic genetic algorithm were written, in the program, the initialization of population, selection operation, crossover, mutation and the decoding of binary code were written subroutines. In the subroutine of the initialization of population, the length of binary coding about the individual of population is determined according to the multiple unknowns and different solution accuracy; In the subroutine of the selection operation, the selective probability calculation method based on roulette was modified accordingly; In the subroutine of the crossover operation and the mutation operation, the individual coding parts corresponding to multiple unknowns were uniform crossed and mutated separately. In this paper, improved the pilot relief valve static characteristic equations were transformed into fitness function containing three unknowns of the valve port opening of pilot valve, the valve port opening of main valve and overflow traffic, the fitness function was solved using genetic algorithm.Genetic algorithm program was written in Matlab language, simulation program and program interface were written in the GUI of Matlab. The simulate program was composed of a main interface and three important sub-interfaces, the main interface was the entrance to the sub-interface, one sub-interface was drawn pilot relief valve opening and closing characteristic curve, one was analyzed the parameters of pilot relief valve, and another search the optimal parameters of pilot relief valve using orthogonal experimental were designed. All parts of the simulation program executed through the genetic algorithm program solving the corresponding fitness function of improved static characteristic equations of the pilot relief valve.In this paper, the simulation program of using genetic algorithm was the supplement of experimental method of the pilot relief valve opening and closing characteristics, and had some significance of designing the various parameters of the pilot relief valve.