Application of jet propellant-8 to premixed charge ignition combustion in a single-cylinder diesel engine

Abstract

The aviation fuel, jet propellant-8, was applied to premixed charge ignition combustion as well as conventional combustion in a single-cylinder diesel engine and was compared with diesel fuel. The engine performance and emissions were tested with and without exhaust gas recirculation under two operating conditions. The liquid- and vapor-phase penetration of diesel fuel and jet propellant-8 were also compared by Mie-scattering and Schlieren method under evaporating conditions using a constant-volume chamber. It was observed that jet propellant-8 exhibited slightly longer vapor-phase penetration and evidently shorter liquid-phase penetration compared with diesel fuel due to the lower distillation temperature and density of jet propellant-8. However, despite the faster evaporation rate of jet propellant-8, it was found that the ignition delay with jet propellant-8 was 2–3 crank angle degrees longer than that with diesel fuel due to its lower cetane number. This result was consistent for all operating conditions and combustion regimes. Jet propellant-8 also showed lower nitrogen oxides (NOx) and smoke emissions for both combustion regimes under the low-load condition because of locally leaner air–fuel mixture caused by longer ignition delay, higher volatility, and lower aromatic contents. As the engine load increased, jet propellant-8 emitted more NOx under conventional combustion regime due to the more vigorous premixed burn phase compared with diesel fuel. With exhaust gas recirculation, jet propellant-8 showed an improved trade-off relationship between NOx and smoke emissions for both combustion regimes due to its better evaporation characteristics and lower aromatic contents. Premixed charge ignition combustion with jet propellant-8 emitted lower smoke than conventional combustion with jet propellant-8 under near-zero NOx level.

From fundamental study to practical application of kerosene in compression ignition engines: An experimental and modeling review

“…53 From Figures 5(c), 6(a), and 7, it can be observed that kerosene and diesel sprays are generally quite similar except for some minor differences. 49,53,81 Due to kerosene’s lower density and higher volatility as compared to diesel, kerosene’s liquid penetration was seen to be shorter than diesel. 53,81 However, this difference was less obvious when the ambient density was higher as spray behavior became dominated by ambient condition.…”

“…The pioneering work was done by the group from SNL which consisted of Pickett and Hoogterp 81 as well as Kook and Pickett. 49,87,88 Following their lead, others who had contributed to this area were Lee and Bae, 5 Park et al, 53 Jing et al, 89 Kang et al, 66 Song et al, 90 and the authors’ research group. 91,92…”

“…53 Figure 7(a) shows the sprays of kerosene and diesel at an ambient condition of 723 K and 11.38 kg/m 3 and an injection pressure of 50 MPa. 53 On the other hand, Figure 7(b) and (c) shows the vapor and liquid penetrations at different ambient conditions of 723 K/11.38 kg/m 3 and 925 K/23.39 kg/m 3 , respectively, with two different injection pressures. 53 From Figures 5(c), 6(a), and 7, it can be observed that kerosene and diesel sprays are generally quite similar except for some minor differences.…”

“…53 On the other hand, Figure 7(b) and (c) shows the vapor and liquid penetrations at different ambient conditions of 723 K/11.38 kg/m 3 and 925 K/23.39 kg/m 3 , respectively, with two different injection pressures. 53 From Figures 5(c), 6(a), and 7, it can be observed that kerosene and diesel sprays are generally quite similar except for some minor differences. 49,53,81 Due to kerosene’s lower density and higher volatility as compared to diesel, kerosene’s liquid penetration was seen to be shorter than diesel.…”

Editorial: Thermo- and fluid-dynamic processes in direct injection engines – THIESEL 2014 Special Issue

“…Selected papers include two papers related to fuel injection, 4,5 two papers on turbocharging 6,7 and seven papers on combustion. [8][9][10][11][12][13][14] With respect to the articles selected for the injection part, in the work of Watanabe et al, 4 the visualization of cavitation inside real-size nozzles is presented for different nozzle seats changing the sac volume, finding that vortex flow within the sac affects the spray characteristics at the beginning of needle lift. 3 The visualization of the cavitation phase in real-size nozzles has been a very active research work as could be observed from the work of Reid et al 15 To pass from fuel injection system to combustion, the most common situation is to use one-dimensional code for injection modelling 16,17 or to make use of zero dimensional codes for the prediction of spray characteristics.…”