Ignition phenomena of electric wires carrying short-term excess electric currents were investigated in microgravity with experiments and calculations. Microgravity experiments were conducted in 100 m and 50 m drop towers and calculations were carried out with a one dimensional cylindrical coordinate system. The experimental results showed that the limiting oxygen concentration (LOC) under a giv...

Homogeneous charge compression ignition technology has exhibited high potential to reduce fuel consumption and NOx emissions over normal spark-ignition engines significantly. Optimized kinetic process technology is implemented to realize homogeneous charge compression ignition combustion in a port fuel injection gasoline engine. The combustion and emission characteristics are investigated with ...

The ignition temperature of nitrogen-diluted dimethyl ether (DME) by heated air in counterflow was experimentally determined for DME concentration from 5.9% to 30%, system pressure from 1.5 to 3.0 atm, and pressure-weighted strain rate from 110 to 170 s . These experimental data were compared with two mechanisms that were, respectively, available in 1998 and 2003, with the latter being a substa...

High-repetition-rate laser-induced fluorescence measurements of fuel and OH concentrations in internal combustion engines are demonstrated. Series of as many as eight fluorescence images, with a temporal resolution ranging from 10 micros to 1 ms, are acquired within one engine cycle. A multiple-laser system in combination with a multiple-CCD camera is used for cycle-resolved imaging in spark-ig...

Wildland fire in the South commands considerable attention, given the expanding wildland urban interface (WUI) across the region. Much of this growth is propelled by higher income retirees and others desiring natural amenity residential settings. However, population growth in the WUI increases the likelihood of wildfire fire ignition caused by people, as humans account for 93% of all wildfires ...

This paper is devoted to the study of semilinear degenerate elliptic boundary value problems arising in combustion theory which obey the simple Arrhenius rate law and a general Newton law of heat exchange. We prove that ignition and extinction phenomena occur in the stable steady temperature profile at some critical values of a dimensionless rate of heat production. 2000 Mathematics Subject Cla...

A one-dimensional numerical model and theoretical analysis involving both surface and in-depth radiative heat flux absorption are utilized to investigate the influence of their combination on ignition of PMMA (Polymethyl Methacrylate). Ignition time, transient temperature in a solid and optimized combination of these two absorption modes of black and clear PMMA are examined to understand the ig...

Editor – We appreciate the comments of P.J. Landrigan concerning our article on the factors associated with elevated blood concentrations in children in Karachi, Pakistan (1, 2). In his editorial, however, he commented that the decline in the use of leaded petrol in Pakistan had resulted in declines in children's blood lead levels. Mean blood lead concentrations in schoolchildren had been repor...