Study On Key Components Of High Pressure Pump In Common Rail System

The prosperity of the auto market has brought great economic benefits to society, but it also caused serious environmental and energy problems. The clean energy vehicle such as electrical high pressure common rail system has become a new hot research topic. For the advantages of low pollution, low energy consumption and high power rate, electrical high pressure common rail system has gained wide acceptance. It's recognized as the future direction of the diesel vehicle. High pressure pump is the key hydraulic component of common rail system.The low pressure fuel from engine tank is compressed into high pressure fuel by high pressure pump,which is to meet the need of fuel injection. The maximum injection pressure depends on the design of high pressure pump. The emission regulation, which becomes stricter and stricter, pushed the high pressure pump into the direction of producing and bearing higher and higher pressure. Therefore,the research on high pressure pump of common rail system has important practical significance.This thesis designed one high pressure pump with the rated pressure 1600 bar for LPV common rail system. The key points are the several important components of high pressure pump which deside the maximum injection pressure, like camshaft, piston elements, and inlet and outlet valves. Firstly, this thesis designed one in-line piston pump for fulfilling the Euro IV emission regulation, and built the 3D model of key components of high pressure pump. Then this thesis did research on camshaft, doing the finit element anaysis on camshafts with different cam curves and analyzing the effection of different cam curves on fuel delivering capacity of high pressure pump. Afterwards, this thesis built the mathmetical models of fuel leakage between piston and barrel and fuel valves, and did finit element analysis on them, analyzing the radical deformation and structural stress under high pressure. According to the result, this thesis supplied several methods to optimize these components. Finally, this thesis did simulation on the high pressure pump model and made comparasion between simulation result and platform test result, aiming at validating the reliability of designed high pressure pump.This thesis researched on the key components of high pressure pump, the results of this research can provide reference for the electrical common rail system technology. The designed key components can offer theoretical support in the raliable development of higher pressure pump in common rail system.