Ignition is the initial stage of burning the materials. Consequent flame spread over the materials, heat release rate, fire spread across the rooms, and other issues for building fires all depend on that. Ignition of cellulose materials is commonly classified as smoldering or glowing ignition (self-heating ignition) and flaming ignition including piloted and spontaneous ignition. Numerous studi...

We report on the design and output performances of a diode pumped, high-peak power Nd:YAG/Cr 4+ :YAG laser with four-beam output. The system posses the ability to chose independently the focus of each laser beam, being seen as a solution for a laser spark with multiple-point ignition. The laser ignition of a gasoline direct injected engine has several advantages in comparison with ignition by e...

the paper presents results of experimental studies on the methane and propane ignition process in various volumetric compositions of oxidizers heated to temperatures higher than ignition point of analyzed fuels (htac conditions–high temperature air combustion conditions). the increment of temperature dt and the ignition delay time tig are parameters characterizing the process of ignition under ...

The ignition delay times of methane/air mixture diluted by N2 and CO2 were experimentally measured in a chemical shock tube. The experiments were performed over the temperature range of 1300-2100 K, pressure range of 0.1-1.0 MPa, equivalence ratio range of 0.5-2.0 and for the dilution coefficients of 0%, 20% and 50%. The results suggest that a linear relationship exists between the reciprocal o...

Non-equilibrium plasmas may be used to dissociate reactants into radicals. In turn, these radicals react releasing energy and broadening the radical pool and thereby ignite or aid the ignition of a fuel=air mixture. Using methane as an archetypical fuel, this work studies the kinetic pathways that control homogeneous ignition in the presence of radicals, which were previously formed by external...

In this work, the effect of seven different sample orientations from 0° to 90° on pilot and non-pilot ignition of PMMA (poly(methyl methacrylate)) exposed to radiation has been studied with experimental and numerical methods. Some new and significant conclusions are drawn from the study, including a U-shape curve of ignition time and critical mass flux as sample angle increases for pilot igniti...

Lean fuel/air mixtures with various fuel/fuel ratios between methane and n-butane were supplied to a premixed compression-ignition engine (i.e. homogeneous charge compression ignition engine, HCCI) with or without supplementary gaseous formaldehyde induction as an ignition controlling additive. In the no additive case the methane and butane function as the two fuels in the high/low-octane two-f...

High-speed digital imaging has been used in rapid compression facility (RCF) studies to investigate ignition phenomena of iso-octane/air mixtures. Sequential images were captured for each experiment. The results indicate the existence of two ignition regimes. In one domain, ignition is rapid, typically less than 76 μs, and ignition occurs simultaneously throughout the test volume. In the other ...

This talk will describe ongoing and planned fast ignition theoretical and experimental work using the Z-machine in concert with the upgraded Z-Beamlet/PW laser system. Z can produce x-ray powers of 100-250TW, x-ray energies 1-1.8MJ, and > 200eV radiation temperatures and thus represents an interesting platform for compressing large quantities of matter for use as fast ignition targets. Soon Z w...