Hydraulic pump is the most important component in the hydraulic system. It plays a role to convert fluid energy into mechanical energy. Rapid pressure fluctuation occurring in the cylinder chamber of the hydraulic pump is the cause of the pressure pulsation, noise and cavitation. The main purpose of this study is to simulate the influence of modified shape of notch on the pressure pulsation. To date, the study of the simulation analysis for hydraulic pump has been performed using 1-D analysis due to the complexity of the internal geometry of the pump. Performance characteristics of various valve plate notch shapes are studied by using 3-D numerical method. Three kinds of valve plate having the conventional notch, the low-noise type notch and the newly designed cylinder type notch, respectively, were analysed by using CFX. Pressure pulsation in the cylinder chamber for the valve plates with the conventional and the low-noise type notch could be lowered 0.5 ~ 0.8 bar in average by using the newly designed cylinder type notch. The difference in their peak pressure reached up to 4 ~ 5 bar. Decrease in the pressure pulsation of about 0.2 ~ 0.4 bar was attained at the discharge port of the pump having the newly designed cylinder type notch.
The result can be applicable to the reduction of the pressure pulsation, which is very important for designing a low noise hydraulic pump.