The influence of corners on the ignition of a solid exposed to a surface energy flux is analyzed with large activation energy asymptotics. We begin with the analysis of the ignition of semi-infinite wedges by a constant heat flux. Two stages and two spatial zones, reactive and inert, are found. The ignition stage can be described by a slowly convergent asymptotic expansion for the increment in ...

To characterize the ignition process in homogeneous charge compression ignition engines, high fidelity simulations are performed to study the effects of different initial temperature distributions on the autoignition of a turbulent homogeneous mixture at high pressure. The effects of the initial temperature distribution on the ignition and subsequent heat release are studied by comparison of si...

Ignition processes in the hydrogen-oxygen system were simulated by solving the corresponding conservation equations (i.e., conservation of mass, energy, momentum, and species mass) for one-dimensional geometries using a detailed reaction mechanism and a mUltispecies transport model. An additional source term in the energy conservation allowed the treatment of induced ignition, and a realistic m...

In order to understand better the auto-ignition process in an HCCI engine, the influence of some important parameters on the auto-ignition is investigated. The inlet temperature, the equivalence ratio and the compression ratio were varied and their influence on the pressure, the heat release and the ignition delays were measured. The inlet temperature was changed from 25 to 70 °C and the equiva...

Catalytic partial oxidation (CPO) of methane to syngas has received considerably interest recently as a way to utilize remote natural gas resources. Despite this interest, the mechanism of methane CPO is not completely understood. For example, there is disagreement in the literature if syngas is formed directly from oxidation or whether an indirect mechanism is responsible. Investigation of the...

Direct measurements of intermediates of ignition are challenging experimental objectives, yet such measurements are critical for understanding fuel decomposition and oxidation pathways. This work presents experimental results, obtained using the University of Michigan Rapid Compression Facility, of ignition delay times and intermediates formed during the ignition of n-butanol. Ignition delay ti...

Auto-ignition and combustion of single fuel droplets of methanol, n-heptane and iso-octane are studied. The numerical simulations are based on a detailed vaporization model, a detailed transport model and detailed chemical kinetics. The governing equations of the two phases are solved in a fully coupled way. The influence of different physical parameters like droplet temperature, gas phase temp...

Laser ignition has been discussed widely as a potentially superior ignition source for technical appliances such as internal combustion engines. Ignition strongly affects overall combustion, and its early stages in particular have strong implications on subsequent pollutant formation, flame quenching, and extinction. Our research here is devoted to the experimental investigation of the early st...

Experiments were conducted to characterize fire properties of wood exposed to the certain external heat flux and under variety of wood moisture content. Six kinds of Indonesian wood: keruing, sono, cemara, kamper, pinus, and mahoni were exposed to radiant heat from a conical heater, result in appearance of a stable flame on the wood surface caused by spontaneous ignition. A thermocouple K-type ...