Viewed on a hydrodynamic scale, flames in experiments are often thin so that they may be described as gasdynamic discontinuities separating the dense cold fresh mixture from the light hot burned products. The original model of a flame as a gasdynamic discontinuity was due to Darrieus and to Landau. In addition to the fluid dynamical equations, the model consists of a flame speed relation descri...

Title of Document: Upward Flame Spread Over Discrete Fuels Colin H. Miller, Master of Science, 2014 Directed By: Dr. Michael J. Gollner, Assistant Professor, Department of Fire Protection Engineering Upward flame spread over discrete fuels has been analyzed through experimental research on vertical arrays of alternating lengths of PMMA and insulation. By manipulating the lengths of the PMMA fue...

The present study is aimed at predicting downward flame spread characteristics over poly(methyl methacrylate) (PMMA) with different sample dimensions in different pressure environments. Three-dimensional (3-D) downward flame spread experiments on free PMMA slabs were conducted at five locations with different altitudes, which provide different pressures. Pressure effects on the flame spread rat...

Flame holders are widely used in ramjet combustors. We propose using surface nanosecond-pulsed surface-dielectric-barrier-discharge (NS-DBD) to manipulate the flame-holder flow field experimentally. The electrical characteristics, induced performance, and temperature distribution of NS-DBD were investigated via optical measurement system. In filamentary discharge mode, energy rose with decrease...

This paper describes an analysis of acoustic wave scattering by turbulent premixed flames with moving, convoluted fronts that have random and possibly fractal characteristics. Such interactions play a role in the characteristic unsteadiness observed in turbulent combustion processes. The problem is posed with an integral formulation of the wave equation and assumes that the smallest scales of f...

The speed of propagation of a premixed turbulent flame correlates with the intensity of the turbulence encountered by the flame. One consequence of this property is that premixed flames in both laboratory experiments and practical combustors require some type of stabilization mechanism to prevent blow-off and flashback. The stabilization devices often introduce a level of geometric complexity t...

Turbulent premixed combustion is a major active research topic in combustion science. A number of computational studies have focused on idealized configurations to aid in interpreting flame dynamics observed in the laboratory, including one-dimensional strained flames, two-dimensional vortex/flame interactions and limited three-dimensional direct numerical simulations. In this paper, we present...

Concern has mounted over health effects caused by exposure to flame retardant additives used in consumer products. Significant research efforts have focused particularly on exposure to polybrominated diphenyl ethers (PBDEs) used in furniture and electronic applications. However, little attention has focused on applications in textiles, particularly textiles meeting a flammability standard known...

The large range of time and length scales involved in type Ia supernovae (SN Ia) requires the use of flame models. As a prelude to exploring various options for flame models, we consider, in this paper, high-resolution three-dimensional simulations of the small-scale dynamics of nuclear flames in the supernova environment in which the details of the flame structure are fully resolved. The range...

We consider the grid resolution necessary to resolve combustion in a mixture of calorically imperfect ideal gases described by detailed kinetics and multicomponent transport. Using the steady premixed laminar flame as a paradigm, the required spatial discretization to capture all detailed physics in the reaction zone is found via 1) determination of the finest grid used in a standard software t...