Effects of Injection Pressure and Ambient Gas Density on Fuel - Ambient Gas Mixing and Combustion Characteristics of D.I. Diesel Spray

Abstract

I would like to express my greatest gratitude to my supervisor, Prof. Keiya Nishida, who grants me the opportunity to study in his laboratory and provides me with kind guidance and tutorship not only in the scientific research but also in the everyday life. It is impossible for me to achieve this accomplishment within the three years without his patient and thoughtful instruction. I also would like to thank the associate Prof. Yoichi Ogata in our laboratory, his kind instruction especially his experience in numerical simulation facilitates our research. I express my special compliment to China Scholarship Council (CSC), a non-profit institution affiliated with the Ministry of Education of China, who sponsors me the living expense in Japan. The China General Consulate in Osaka gives us the immediate response and suggestion as soon as we have need.

Set-off length reduction by backward flow of hot burned gas surrounding high-pressure diesel spray flame from multi-hole nozzle

“…Ha et al 48 measured the history of the gas-flow velocity distribution surrounding a transient single spray using hot-wire anemometry. Zhu et al 49 measured the distributions of the ambient gas-flow velocity by PIV under non-evaporating and evaporating conditions. Rhim and Farrell 50 and Malbec and Bruneaux 25 measured gas-flow characteristics surrounding transient diesel sprays injected from a multi-orifice nozzle using PIV.…”

“…Figure 30 illustrates the flow velocity distribution surrounding the transient sprays a short time ASOI. The gas-flow velocity distributions surrounding the downstream region of the transient spray are summarized based on past measurements 23,25,44,[48][49][50] and are combined with the flow patterns in the quasi-steady region close to the nozzle (inside the spherical control volume) which are shown in Figure 3. Fujimoto et al 23,44 measured the flow velocity distribution surrounding the transient sprays at 0.5 ms ASOI under non-combusting conditions using the smoke-wire method.…”

“…The amount of mixed gas passing through the spray tip surface appears to be higher early in the injection event. Similarly, Zhu et al 49 quantitatively analyzed the entrained gas volume passing through the conical envelope (region I) and the mixed gas volume around the spray tip under non-evaporating and evaporating conditions. They divided the spray tip region (which Fujimoto called the ''diffusion part'') into two parts: regions II and III.…”

An investigation of the effects of fuel injection pressure, ambient gas density and nozzle hole diameter on surrounding gas flow of a single diesel spray by the laser-induced fluorescence–particle image velocimetry technique

“…Detailed information can be found in previous work. 16 Experimental conditions Table 1 shows the experimental conditions. The constant volume vessel was charged with nitrogen gas at room temperature (300 K) to reach the desired pressure.…”

Visual Analyses of End of Injection Liquid Structures and the Behaviour of Nozzle Surface-Bound Fuel in a Direct Injection Diesel Engine

“…The majority of the surface-bound fuel was removed from the injector nozzle by high velocity in-cylinder gas passing across the injector surface ( Figure 10D). Although most, if not all, of the surface-bound fuel in a firing engine would vaporise before intake valve opening [38,40,43], any fuel in the cylinder at this time would have detrimental effects on the subsequent combustion event [44]. A main splashing event occurred at 208±2 CAD BTDC in which a large proportion of the fuel was projected into the cylinder followed by several smaller splashing events over the proceeding 20 crank angles ( Figure 10C).…”