Research On Simulation Of Effects Of High Pressure Pump Structural Parameters On The Fluctuation Of Rail Pressure

This paper aims to study the effects of high pressure pump structureparameters adjustment for rail pressure fluctuations. Bosch CP1H typehigh-pressure pump is used as the foundation, GT-FUEL software ofGT-SUITE software group is used as tools to establish the high pressure pumpmodel. In cooperation with GuangQi Jiao.We got the artery chromatogram ofthe high pressure common rail system on the platform for stability conditionand to verify this model.After analysis the structure characteristic and work principle of high pressurepump and CP1H Bosch Bosch common rail in-depth. determine the pump torail to we got some structural parameters that produce evident effects of highpressure common rail fluctuations. That is: inner valve spring stiffness, springpreloaded force, the quality of the ball valve, piston, piston stroke in diameter.Set different values to the main structure parameters in high pressure pumpmodel. Comparison and analysis with the model simulation calculations ofdifferent pressure fluctuation curves rail, on the different parameters on the railpressure fluctuations. This paper draw some conclusions through comparingpressure fluctuation curves rail with different structural parameters:Inlet and outlet valve body quality is hours, rail pressure fluctuation extent wassmall.Inlet valve spring pre-tightening force take smaller value rail pressurerelatively stable.Spring stiffness is big, in early, inlet valve prone to open andshut off many times.that is not only influence the stability of the oil supplypressure, and will impact the seat longevity.Relative to inlet valve structure parameters, changes of injection phase, pistondiameter and structural parameters of outlet valve are more apparent to railpressure fluctuations.Smaller diameter of piston set value, circulation oil supply to decrease,high-pressure pump can’t satisfy every cycle of injection system injectionquantity and control the amount of oil consumption injector, high pressure oilrail not enough pressure to keep rail pressure stability.In order to ensure evenness of each cylinder circulation injection quantity,matched high-pressure pump and engine speed to ensure that the number ofuniform is fit to cylinderIt is suitable that increase the flow of, improve the stability of injection systemby changing the shape of the CAM contour line appropriate when ensure highpressure pump cycle in the flow of range allows, with in satisfying the highpressure common rail system cycle injection quantity. A smaller oil valve spring pre-tightening force can be selected out, to ensurethe stability of the oil valve opens, reduce the system pressure fluctuations, thereason is same to analysis of inlet valve spring pre-tightening force.