Improving the quality of heat dissipation analysis in marine diesel by clarifying the upper dead center position of the piston

It is declared that an increase in the technical, economic and environmental performance of the diesel engine can be achieved by controlling the combustion process of fuel by influencing the parameters of the fuel equipment and combustion chamber. Information about the combustion process is obtained by registering in the experiment and analyzing the indicator diagram. The purpose of the study is to assess the possibility and identify means to improve the quality of the analysis of the combustion process in the ship diesel engine by obtaining reliable characteristics of heat release during fuel combustion as a result of the analysis of indicator diagrams. It is shown that the known methods and means of obtaining heat release characteristics do not provide sufficient analysis accuracy. It is proved that the heat dissipation characteristics can be distorted as a result of an error in determining the ordinate axis on the indicator diagram corresponding to the position of the upper dead center of the piston. A technique for high-precision determination of the upper dead center position, which is determined by dividing in half the time interval between two signals corresponding to the same position of the piston during its ascending and descending motion, is proposed. A device has been developed to implement this technique. Using it in practice makes it possible, by ensuring the necessary accuracy of indicating the upper dead center position on the indicator diagram, to improve the quality of the computational and experimental determination of the heat release characteristics during fuel combustion, which, in turn, allows to provide high technical, economic and environmental performance of the diesel engine during its manufacturing and improve the quality of its diagnosis during operation.