Experimental investigation of the combustion process and efficiency of a diesel engine in the case of biodiesel fuel application

Abstract

In wine-producing regions, oil extracted from waste grape seeds can be used as a feedstock for biodiesel production. This paper presents the results of experimental research on combustion process parameters and engine efficiency when using conventional diesel fuel (D100) and blends of conventional diesel fuel with biodiesel produced from waste grape seed oil. Four biodiesel–diesel blends with biodiesel contents of 7%, 14%, 21%, and 28% by volume (B7, B14, B21, and B28) were used. The tests were conducted on a single-cylinder direct injection diesel engine at full load at engine speeds of 1635 rpm, 1937 rpm, and 2239 rpm. It was found that all blends exhibited a higher peak (maximum) heat release rate (HRR) and higher peak (maximum) cylinder pressure than D100. Blends with higher biodiesel contents (B21 and B28) had the heat release centroid located closer to top dead center (TDC), which is favorable for indicated thermal efficiency (ITE). The engine achieved a higher brake thermal efficiency (BTE) with the B14 blend (0.296 at 1635 rpm, 0.324 at 1937 rpm, and 0.277 at 2239 rpm) than with the B7, B21, and B28 blends. In terms of engine efficiency, the B14 blend exhibited performance comparable to that of D100.