Abstract: Hydraulic confined piston engine is a new type hydraulic power system. The valve type orifice system is an indispensable component in it. The optimization design of the valve type orifice system can shorten design cycle significantly and improve design project so as to achieve the aim of improving the whole engine quality. Based on the optimization technology, the overall objective function is achieved through liner weighted method of cubage efficiency and valve life. The optimization model of valve type orifice system of hydraulic confined piston engine is built. The optimization design is carried out by using Matlab language and the optimization mathematic model is resolved. The results before and after optimization are analyzed. After optimization, the impact forces of inlet valve and outlet valve drop 48.77 percent and 44.50 percent respectively, and the cubage efficiency rises 10.06 percent. The results indicate that the arithmetic is feasible and effective. The experimental work of this system is carried out, and the change of outlet valve pressure and flow rate along with the change of speed and accelerator is studied. The experimental results are very close to the simulation results, and the error is within 6 percent, thus verifying the correctness and precision of the optimization model of valve type orifice system of hydraulic confined piston engine.

Key words: Experimental verification, Optimization design, Valve type orifice system