Research On Diesel Engine Emission Control Of Shunting Locomotive

With the increasingly severe environmental problems,the United States,Europe,and the International Railway Union have formulated more and more stringent emission regulations,and it is imperative to control diesel emissions from diesel locomotives.The purpose of shunting locomotives is mainly shunting operations and small operation operations in railway yards.Due to the special nature of the work,the diesel engine of the shunting locomotive operates at low power idling more than 80%of the time.At this time,due to the reduction in the number of cycles and the decrease in the intake air volume and fuel injection volume,the cylinder pressure of the diesel engine is idling and the temperature is low,and the incomplete fuel combustion leads to a substantial increase in soot emissions.In order to solve this phenomenon,this paper uses CAE software GT-SUITE to conduct modeling and simulation analysis for the 12V240ZJ diesel engine equipped with DF₇G shunting locomotive.The main content of this article are:First,the evolution of emission standards for diesel locomotives at home and abroad and the requirements for shunting locomotives are explained;The formation mechanism and hazards of the main harmful substances and the commonly used control methods are analyzed;Carry out mathematical modeling and basic theoretical calculations for each system of the selected diesel engine;Establish a simulation model of the main structure of the 12V240ZJ diesel engine;The influence of various influencing factors on diesel engine performance and emissions was discussed in depth,and improvements were proposed;Finally,cylinder deactivation is designed for the diesel engine at low speed and no load.The simulation results are:（1）After the simulation optimization scheme,the working process in the cylinder of the diesel engine is optimized,so that the output power is increased while the fuel consumption rate is reduced,the emission is controlled,and the soot emission under low-speed operating conditions is significantly reduced.（2）The cylinder deactivation design improves energy efficiency and significantly reduces soot emissions at low speeds.The oil cut-off cylinder stop effectively improves the engine’s indicating efficiency and effectively reduces the total circulating fuel injection and fuel consumption rate.After the oil cut-off cylinder is used,the diesel engine output torque changes with the crankshaft angle basically the same as the original engine.The platform used in the research and improvement of this paper is GT-SUITE software.