Structure Optimization Of Electronic Unit Pump Fuel Injection System For Diesel Engine

With the rise of international oil prices and the increasing strict limits of NOx emission, marine diesel engine is facing with double challenges which are economic performance and emission performance. Diesel engine fuel injection system for diesel engine electronic control modification is a effective measure to achieve energy conservation and emissions reduction. In this paper, the research is 4190 type diesel engine electronic control unit pump fuel injection system which is mainly used for high power diesel engine. Its main advantages include high injection pressure, injection starting point and end point control flexibility and good system stability, and is mainly used for high power diesel engine.This paper apply in AMESim simulation software building Electronic control unit pump single-cylinder fuel injection system model and validate the model. Also, it has analyzed the influence and reasons of electric pump structure parameters to spray characteristics.First of all, AMESim software are used to set up the model of control combination single-cylinder fuel injection pump system, then testing the data of diesel engine under different working conditions of injection pressure and injection rate, and using the experimental data verified the model.The validation results show that the model has high accuracy and satisfies the requirement of the simulation calculation. The model can analysise the influences on the characteristics of injector which caused by the factors such as CAM shape linear velocity, length of plunger diameter, high pressure tubing and high pressure oil pipe diameter and the aperture of jet.Meanwhile it explains the reason of that. The outcome shows that the form of a linear velocity of the CAM, plunger diameter and the aperture of jet has a greater influence to injector characteristics, and high pressure tubing length and high pressure oil pipe diameter has little effect on characteristics, and determined the high-pressure tubing length is 800 mm, high pressure oil pipe diameter is 2.0 mm.Secondly, the orthogonal experiment design method optimized electric pump structure parameters combination, and orthogonal table selected the eligible parameter combination are used. Two groups optimization results are: CAM type linear velocity of 0.46 mm / ° CA, plunger diameter 15 mm CAM form linear velocity, nozzle aperture 0.26 mm and 0.26 mm / ° CA, plunger diameter 15 mm, nozzle aperture 0.27 mm, and analyzed the two groups optimized results of the fuel injection lawFinally, simulated analyzed the economy and emissions of the two groups of optimization results are analysiseb by Simulation analysis through the software FIRE combustion model, and compared with the original machine. Results show that compared with the original machine, two sets of optimization results economy improved, and A machine is optimal.