DIESEL SPRAY CHARACTERISTICS OF MULTI-HOLE INJECTORS UNDER GEOMETRICAL SIMILARITY CONDITION

Small-bore engines are popular due to low CO<sub>2</sub> emissions and low fuel consumption. To simplify the design steps for various engine sizes, similarity theory was applied to engines. In this paper, the spray characteristics of non-evaporating sprays for multi-hole diesel injectors under the geometrical similarity condition were investigated by diffused background illumination (DBI). The similarity theory is based on Chikahisa theory, Wakuri momentum theory, and Inagaki analysis of geometrical similarity. Under the similarity condition, the injectors with hole diameters of 0.07, 0.101, and 0.133 mm were used at injection pressures of 45, 93, and 160 MPa, respectively. In addition, the…