Analysis and development of the heat exchanger for the exhaust gas recirculation system of the transport diesel engine

Abstract

Nowadays one of the most urgent problems of creating modern combustion engines (ICE) is the problem of ecology. Ensuring environmental requirements is usually associated with the introduction of new structural elements or the modernization of existing structures, since practice shows that the use of traditional methods to reduce the toxicity of exhaust gases, leads to a gradual deterioration in the fuel economy of the engine. This article discusses the use and development of an exhaust gas recirculation system for a transport diesel as the most effective means of reducing NOx emissions into the environment. On the example of expert data, the experience of using exhaust gas recirculation systems in diesel engines is considered, and their main advantages and disadvantages are given. The use of «cooled» exhaust gas recirculation is more preferable than «uncooled», since the filling of the cylinders with an air charge improves, and lower gas temperatures during the combustion period are provided, thereby reducing the amount of NOx generators. It is also noted in the work that when a cooled exhaust gas recirculation system is used in conjunction with optimization of engine design and adjustment parameters, NOx emissions are reduced with minimal deterioration of the engine's power and economic parameters. On the example of research and simulations on the testbench of the transport engine 8ChN 12/13, the efficiency of the exhaust gas recirculation system on diesel has been estimated and all the necessary data was provided. Due to the optimization of the adjusting parameters and the developed model of the exhaust gas recirculation system, it was possible to achieve 46 % reduction in NOx emissions. It has been shown experimentally that the use in a diesel engine of a theoretically developed organization of working processes with the use of recirculation of exhaust gases and the characteristics of controlling the main adjustments of the combustion process is advisable.