高压油泵阻尼孔对燃油系统压力特性的影响研究OACSTPCD

To achieve higher thermal efficiency and better emissions,the spraying pressure of diesel engines has continually increased over the years.As a key structure of the constant-pressure delivery valve of the high-pressure fuel pump,the damping orifice has a significant effect on the pressure characteristics of the fuel system.In this pa-per,the influence of orifice diameter on the spraying characteristics of oil sprayers and the pressure fluctuation characteristics of a high-pressure fuel pipe were investigated.The results showed that when the orifice diameter in-creases from 0.1 to 2.0 mm,the oil spraying duration of the oil sprayer is relatively shortened,and the cyclic spra-ying volume reduces because different orifices correspond to different residual pressures of the fuel pipe,and differ-ent orifices have different system pressure regulation speeds.Furthermore,when the orifice is small(0.1 mm),secondary spraying occurs;when the orifice is excessively large(3 mm),an area with zero pressure in the system also emerges,i.e.,there is a risk of cavitation erosion.The spectral analysis of the residual pressure in a high-pressure oil pipe demonstrated that when the damping orifice is small,there is a strong correlation between the pres-sure pulsation in the high-pressure fuel pipe and the movement of the outlet valve;when the damping orifice is large,the pressure pulsation is related to the movement of the return valve,i.e.,the motion of various valves in the fuel supply system is the primary cause of the pressure pulsation in the high-pressure oil pipe.