Вибір та обґрунтування параметрів автотракторного дизеля при його роботі на водопаливній емульсії

Abstract

Thesis for the science degree of the Candidate of technical sciences by speciality 05.05.03 – engines and power plants. National Technical University "Kharkiv Polytechnic Institute", Kharkiv, 2019. The thesis is devoted to solving the problem of complex improvement of the environmental and economic indicators of a diesel engine operating on a water-fuel emulsion (WFE), through the choice of rational diesel engine parameters. The physicochemical properties of water-fuel emulsions were investigated. Experimental research of the influence of WFE on the performance and workflow of a diesel engine have been carried out. A method has been developed for determining the moment of the start of fuel combustion based on the results of experimental research, which allows to increase the accuracy by taking into account the features of the pressure sensor. According to the results of computational and experimental research of a diesel engine operating on WFE, the activation energy of this type of fuel and the coefficient of excess air in the cylinder were determined. The peculiarity of the calculation method is a separate definition of indicators for each diesel operating cycle. A complex mathematical model of a diesel engine on a water-fuel emulsion has been developed, which allows carrying out computational research of a diesel engine taking into account the characteristics of WFE of any composition. The model takes into account the action of the mechanism of "microexplosion", the catalytic effect of the products of water dissociation on the processes of combustion and the formation of harmful substances in the cylinder. Using the developed mathematical model, rational values of diesel parameters were determined using water-fuel emulsion. The limitation of the maximum pressure and the maximum rate of pressure increase in the cylinder was introduced in order to prevent a significant increase in mechanical loads on diesel engine parts. The concept of an adaptive diesel control system has been developed, which will automatically ensure rational diesel parameters for WFE of any composition, or for traditional diesel fuel. Works on the selection of the type of water content sensor in WFE were carried out.