The Improvement Of Fuel Injection System Of 16V280ZJ Diesel Engine And Its Research On Simulation

Since the speeding up of railway, the malfunction rate of 16V280ZJ diesel engine has increased by 32%, the repair rate has also increased by 40%, the malfunctions of fuel injection system are followed: the service life of needle valve is short after short time use, the spray and flow quality of fuel injector is bad, delivery valve has serious cavitations, plunger matching parts is blocked down and so on.above phenomenon lead to cylinder knocked,the fuel consumption rate become high. ventpipe is too hot, emit black smoke.some serious phenomenon can lead to parts of diesel engine broken, therefore we should pay attention the design of fuel injection system.This paper mainly improves three matching parts (needle valve, delivery valve, plunger). firstly,we use the advance impact stress theory, through calculating,adopting short needle valve with small mass can reduce the impact stress of needle valve on sealing surface of valve seat.accordingly,we take some improvements to sealed coniacal surface, injection holes, whic h increase the service life of fuel injector;secondly,we change the head of sect of helix instead of only one helix,which can improve the economy of disel engine in part load work conditi ons.There are two improved programmes of delivery valve. The first improved programme is using the constant pressure delivery valve(including main valve and auxiliary valve ) instead of constant volume ,which can reduce the cavation phenomenon; The second improved progra mme is using delivery valve with under seal seat instead of constant volume, which can slow up the impulse of delivery valve.In order to ensure the advance of dynamics and economy of improved fuel injection system,this paper adopt business soft GT-SUITE to simulate the pump-line-injector of fuel injection system.with above steps, quicken empolder process and reduce expense of empold er.this paper make use of FUEL model of GT-SUITE soft,with parts drawings of actural inject ion system.,modeling pump-line-injector of 16V280 type, get cycle injected mass,the lift of needle valve, the pressure of high pressure line and so on results.then we make use of power model of GT-SUITE soft, modeling the singal cylinder engine,predict the maximum pressure in cylinder,fuel consumption rate,the improved fuel injection system is carried on the load experiment of NO.5585 DF8B diesel locomotive in the Xin Xiang mechanical section of Zheng Zhou rail bureau , and now it runs well.