Abstract: The aim of this research is the study of negative physical processes in diesel engines, which are induced by the low value of cetane number of ethanol that characterizes the efficiency of the ignition process. The authors present the calculation assessment of thermodynamic state of methanol and diesel fuel mix combustion products in various proportions and calculations of the thermal state of injector elements by analytical and computational methods. Analytical dependencies are taken from traditional branches of science such as heat engine theory, heat transmission. As a technical solution to compensate the low value of the cetane number the authors use diesel fuel as an ignition dose and ethanol as the main fuel. The paper shows that having other conditions equal the power of a diesel engine slightly increases due to raise of water vapor in combustion products. The authors present the methods and calculation of fuel heating in the boundary layer of the injector nozzle channel during the injection cycle of the D240 diesel engine. With the decrease of the fuel priming in the boundary layer the temperature rises, and that is the reason of the gumming which leads to the needle jamming.
Keywords: Diesel fuel; Ethanol; Ignition dose of diesel
Recieved: 22.12.2021 Accepted: 23.05.2022 UDC: 665.75