Experimental and Theoretical Analysis of the Spray Characteristics of a High-Pressure Common-Rail Injection System Fueled with Neat Biodiesel, Ethanol-Biodiesel Blends, and Neat Diesel Fuel

Abstract

In this study, the spray and atomization characteristics of neat biodiesel, ethanol-biodiesel blends (BDEs), and neat diesel in a high-pressure common-rail injection system were investigated experimentally and analytically. Schlieren-type high-speed photography was utilized to capture the experimental images. The findings indicated that spray penetration and peak tip velocity decreased and the spray cone angle increased with increase in the ratio of ethanol in the blends. Two predictive models were used to generate data to compare with measurements of spray penetration and peak tip velocity. The empirical formula of equivalence ratio, Ohnesorge number, and Sauter mean diameter (SMD) were calculated to evaluate atomization levels.