Ignition and Combustion Characteristics of Diesel Spray Impinged on an Extruded Wall

Ignition and combustion characteristics of diesel spray impinged on an extruded wall, which was a top of cylindrical column, were experimentally investigated. Appearance positions of OH and C2 radical luminosities and luminous flame kernel were stereoscopically observed using a two-way fiber optical system. The extruded column was fixed in a high temperature and high pressure combustion chamber. A diesel spray was impinged vertically to the extruded wall. Effects of cylindrical column diameter (D=5, 10, 15mm, ∞ (flat wall)) on ignition and combustion characteristics were investigated. As the result, appearance position of OH luminosity was observed near the spray tip except for D=∞ (flat wall). The maximum volume of luminous flame impinged on the extruded wall was strongly influenced by the diameter of the column. In a condition of low-ambient temperature, the maximum volume of blue flame on the extruded column of 10 mm diameter was larger than those on other columns.