Analysis of the energy balance of a newly designed opposite piston diesel engine for unmanned aerial vehicles in the event of a change in the fuel injection angle

The article presents the results of energy balance studies of the designed internal combustion engine. This engine is a newly designed opposite piston diesel engine for unmanned aerial vehicles. Tests were carried out on stationary dynamometer. Types of thermal losses occurring in particular engine systems were analysed and their comparison was performed. The results of heat flow tests during the operation of an internal combustion engine and their locations were presented. The following heat streams were analysed: heat stream supplied with air and fuel to the engine, heat streams leaving the engine: useful heat, heat with exhaust gases, heat of cooling and oiling system, losses to the environment as well as incomplete combustion losses. The effect of a change in the fuel injection angle on the heat fluxes in the engine was investigated as part of the analysis of the results. The results are presented in tabular form, line graphs as well as Sankey-type diagrams.