Simulation and Numerical Analysis of the Performance Parameters and Combustion Process of a Biofuel-Powered Compression Engine

This paper presents the analysis and results of the numerical simulation of the biofuel combustion process: namely, the volumetric mixture of diesel oil (ON) and camelina seed oil methyl ester (CSME) in a diesel engine. The mathematical model used in the simulation is based on a four-stroke diesel engine acting as a power generator. To enable simulations depending on the type of biofuel, a model algorithm was developed in the MATLAB/Simulink environment that allowed for the conditions and parameters to be adjusted according to specific test requirements. The numerical simulation was built on the basis of a real stand, in order to confirm the results of previous research both theoretically and in real applications. The calculation approach starts with the elemental composition of the fuel and goes through the intake, compression, combustion, and expansion stages, culminating in the thermal balance of the engine. The mathematical model confirmed the obtained results, which are comparable to the results from the research station. The obtained results confirm the legitimacy of using CSME as an additive to diesel and show its impact on engine performance that can be optimized to achieve the desired results. The use of pure CSME (100%) resulted in an increase in engine power and torque, probably due to the oxygen content of the biofuel molecules and its higher cetane number, which improves its ignition characteristics. However, an increase in unit fuel consumption has been observed, indicating lower energy efficiency compared to clean diesel, which is partially offset by the higher density of biofuel. The model takes into account the physicochemical properties of the fuel, such as the viscosity, cetane number and density, which significantly affect the fuel injection and atomization processes. Although the simulation is based on simplified assumptions, its results highlight the potential of biofuels in heavy transport and their cost-effectiveness as an alternative to fossil fuels. The developed model is used not only to evaluate the engine performance, but also as a tool for assessing the thermal efficiency, and optimizing the composition of the fuel mixture.