An empirical model for the ignition of aluminum particle clouds is developed and applied to the study of particle ignition and combustion behavior resulting from explosive blast waves. This model incorporates both particle ignition time delay as well as cloud concentration effects on ignition. The total mass of aluminum that burns is found to depend on the model, with shorter ignition delay tim...

Ignition and burning characteristics of single aluminum and magnesium particles are experimentally investigated. Burning time, ignition delay, flame temperature, and ignition temperature were measured. The single metal particle (30-100 μm in diameter) is uplifted by an electrodynamic levitator, exposed and ignited by a CO2 laser. The thermal radiation intensity was measured using the photomulti...

Reliable ignition in high-speed flows represents a significant scientific problem with a wide range of practical applications. Scientifically, the ignition processes involve complicated interactions among various aspects of chemical reaction and turbulence, which are not fully understood yet [1]. Reliable ignition in propulsion and power devices is further complicated by practical factors such ...

The objective of this work is to investigate the spray ignition characteristics of diesel and canola-derived biodiesel in a rapid compression machine at the low temperatures (676 816 K) and reduced oxygen concentrations (12 and 18%) that are used in low-temperature combustion strategies of advanced diesel engines. A method for testing ignition delay times and apparent heat release rates at a se...

The National Ignition Facility (NIF), the world's largest and most energetic laser system, is now operational at Lawrence Livermore National Laboratory. The NIF will enable exploration of scientific problems in national strategic security, basic science and fusion energy. One of the early NIF goals centres on achieving laboratory-scale thermonuclear ignition and energy gain, demonstrating the f...

The behaviour of five landscape fire models (CAFE, FIRESCAPE, LAMOS(HS), LANDSUM and SEMLAND) was compared in a standardised modelling experiment. The importance of fuel management approach, fuel management effort, ignition management effort and weather in determining variation in area burned and number of edge pixels burned (a measure of potential impact on assets adjacent to fire-prone landsc...

The effect of steady strain on the transient autoignition of n-heptane at high pressures is studied numerically with detailed chemistry and transport in a counterflow configuration. Skeletal and reduced n-heptane mechanisms are developed and validated against experiments over a range of pressure and stoichiometries. Two configurations are investigated using the skeletal mechanism. First, the ef...

LLE Review, Volume 141 48 Introduction Shock ignition (SI)1–5 is an advanced concept in inertial confinement fusion (ICF)6 that is very promising and has the potential to provide significantly higher gains than conventional hot-spot ignition.7 SI is a two-step process where the fuel compression and ignition phases are separated by applying a highly shaped laser pulse with a duration of several ...

Simulations of forced ignition of non-premixed laminar counterflow flames are used to study the effect of strain rate on ignition success. A one dimensional calculation is performed, using detailed methane chemical kinetics and treating the spark as an instantaneous heat release in an inert mixing layer. Ignition success depends on the mixture composition at the spark location, resulting in lea...

gas motion within the cylinder is one of the major factors that control the combustion process in spark ignition engine. it also has significant impact on heat transfer. both the bulk gas motion and the turbulence characteristics of the flow are important and governing the overall behavior of the flow. an arrangement for obtaining a stratified charge, using port injection, is proposed for a cur...