Diagnosing the Process of Forming Biofuel Combustion Mixtures in Diesel Engines by a Program to Compute Spray Volume

A diesel engine's injection and combustion mixture formation process are essential; it determines the engine's economic, technical, and environmental criteria. When the engine uses biofuel, fuel parameters such as viscosity, density, and surface tension affect the above process. Each engine using a specific fuel type will have to adjust injection parameters such as injection pressure and timing to ensure the injection process and formation of a homogeneous air-fuel mixture. Therefore, through the spray structure, it is possible to diagnose the process of combustion mixture formation, thereby making adjustments to the fuel injection system that will improve engine performance and reduce emissions of toxic exhaust gases. In this study, the article presents the content of building a program to compute spray volume using Matlab software. Through the spray volume, quickly diagnose the process of forming the biofuel-air mixture in the diesel engine combustion chamber, thereby determining the appropriate fuel injection system adjustment. Results of simulation and experimental research on 4CHE Yanmar engines installed on fishing vessels with fuel types DO, B5, B10, and B15 show that the B15 fuel mixture when used for the engine needs to be increased injection pressure is about 10% higher than DO fuel injection pressure.