INFLUENCE OF MULTIPHASE FUEL INJECTION ON THE TECHNICAL AND ECONOMIC INDICATORS OF A TRANSPORTATION DIESEL ENGINE.

Purpose. Selection of parameters of multiphase fuel injection using mechanical fuel pumps for engines of ground transport vehicles and estimated impact of parameters of the fuel injection process on the technical and economic indicators of a forced transport diesel engine. Methodology. Scientific research is based on the use of comparative numerical experiment methods. Modern numerical methods are used to model the process of diesel fuel injection, the processes of mixture formation and combustion, with the assessment of the load on the parts of the crank-and-connecting mechanism (CCM) from the gas pressure forces. Based on the results of the calculations, a compromise option is chosen that provides acceptable fuel economy, the minimum rate of pressure increase during fuel combustion, and the minimum load on the CCM parts. Findings. It was established that when using multiphase fuel injection in a diesel engine of type 6Ch15/15, it is possible to reduce the rate of pressure increase during combustion by almost 1.8 times and to reduce the maximum force from the action of gas ticks on the piston by 16.3 %. In the future, this enables to create reserves to increase the level of engine forcing and improve its performance. Originality. The research made it possible to study the influence of multiphase fuel injection on the stiffness of the combustion process and technical and economic indicators of a highly forced diesel engine. The obtained results allow formulating recommendations for choosing a multiphase fuel injection strategy (the number of injections, their duration and the amount of fuel for each injection). Practical value. Changing the conditions of mixture formation and combustion made it possible to reduce the rigidity of the working process of a highly forced diesel engine, reduce the load on the parts of the crank-and-connecting mechanism from gas pressure forces, and improve the operational performance of the internal combustion engine. [ABSTRACT FROM AUTHOR]