The determination of the rate of heat release in the diesel cylinder taking into account the change in the composition of the working substance

The thermodynamic efficiency of the cycle of the internal combustion engine and its efficiency are related to the law of supply of heat to the working fluid. The characteristics of heat release allow us to evaluate and improve the combustion process from the point of view of the thermodynamic efficiency of the cycle, from thermodynamic positions. To optimize the combustion process in compression-ignition engines, including when working on unconventional fuels, it is necessary to develop an algorithm for determining the rate of heat release, taking into account the current composition of the working fluid, since when working on fuels with a changed chemical composition, the ratio of gases in the combustion products can significantly change. The type of heat dissipation characteristic is determined by the regularities of the combustion of fuel in the cylinder e and the law of displacement of the piston and depends, inter alia, on the composition of the working fluid, which continuously changes during combustion of diesel fuel, increasing volume and mass. Existing methods for calculating the heat dissipation characteristics consider a working body consisting of two components - a fresh charge and combustion products. Such an approach reduces the accuracy of calculations when determining the heat input from the diesel fuel indicator chart operating on fuels with modified chemical composition or on non-traditional fuels, since it does not take into account the change in the heat capacity and internal energy of the combustion products. In this article, a mathematical model to compute the heat dissipation in the cylinder of a diesel engine when operating on diesel fuel for the changes in the working fluid composition. The presented results of calculations for a diesel engine of 2CH10.5/12.0 when operating on diesel fuel at the nominal operating mode correspond to the results of the determination of the integral and differential heat dissipation rate obtained by the well known CNIDI method.