Experimental Determination of Combustion Process Parameters of Biodiesel Fuel Made from Waste Grape Seeds

Biodiesel fuel produced through transesterification is mainly used in blends with conventional diesel fuel. The analysis of combustion process parameters for each specific biodiesel fuel represents the basis for a rational approach to the utilization of available motor fuel quantities. In this study, the heat release rate and cumulative heat release during the combustion of conventional diesel fuel and blends of biodiesel fuel made from waste grape seed oil and conventional diesel fuel were analyzed. The tests were conducted on a single-cylinder, air-cooled diesel engine with direct fuel injection. The combustion of conventional diesel fuel, a blend containing 7% of biodiesel by volume (B7), and a blend containing 14% of biodiesel by volume (B14) was examined. Using blends, especially those with a higher biodiesel content (B14), results in a higher maximum heat release rate compared to conventional diesel fuel, which can have negative implications in terms of mechanical stresses and engine noise. However, the higher combustion rate of the B14 blend, particularly during the combustion of the first 50% of the fuel mass per cycle, can have a positive impact on the fuel economy of the working cycle and the engine as a whole.