the flame propagation through a coal dust-air mixture in a spherical vessel was studied by means of a one-dimensional, arrhenius-type kinetics and quasi-steady model. the model includes the evaporation of the volatile matter of dust particles into a known gaseous fuel (methane) and the single-stage reaction of the gas-phase combustion. effect of venting devices as safety idea and the radiation ...

premixed combustion is widely used for reducing pollutant emission from combustion chambers. however, these systems may be sensitive to complex phenomena such as flashback. in the present study flame, flashback and structure of premixed laminar flames are investigated theoretically. the mathematical model includes the axi-symmetric continuity, navier stocks, energy, and species equations. combu...

In scramjet engines, ignition must take place within a residence time on the order of milliseconds. this study, secure conditions for specified n-octane pyrolysis fuel components used in autoignition or forced-ignition by plasma jet torch high-speed flow were numerically investigated. First, delay combustor and cavity flame-holder was estimated using chemical reaction analysis. Three (n-C8H18, ...

High-fidelity Large Eddy Simulations (LES) are performed to study the effect of hydrogen injection on a lean turbulent CH4/Air premixed flame. An Analytically Reduced Chemistry (ARC) mechanism is used achieve detailed description CH4/Air-H2 chemistry. First, validation this kinetic scheme against GRI-Mech 3.0 presented considering both simplified and complex transport properties. When added mix...

We have recently shown that premixed CH4/air flames anchored behind flame holders can stabilize in two stabilization regimes characterised by the presence or absence of a recirculation vortex [1]. Focus present work is on underlying mechanisms governing without for methane-air flames. revisit definition anchoring location and define new which results from stretch considerations rather than heat...

The four processes involved in the flammability of materials are described and related to the various flame retardance mechanisms that may operate. Following this the four practical approaches used in improving flame retardance of materials are described. Each approach is illustrated with a number of typical examples of flame retardants or synthetic procedures used. This overview of flammabilit...

Extinction limits and flame bifurcation of lean premixed dimethyl ether-air flames are investigated numerically using the counterflow flame with a reduced chemistry. Emphasis is paid to the combined effect of radiation and flame stretch on the extinction and flammability limits. A method based on the reaction front is presented to predict the Markstein length. The predicted positive Markstein l...

A FAMILY of inequalities concerning inner products of vectors and functions began with Cauchy. The extensions and generalizations later led to the inequalities of Schwarz, Minkowski and Holder. The well known Holder inequality involves the inner product of vectors measured by Minkowski norms. In this paper, another step of extension is taken so that a Holder type inequality may apply to general...