Flame spreading is a very important phenomenon in the hazard assessment for fire, which is a key element in providing fire safety in buildings with engineering performance-based fire codes. A mathematical model is presented in this paper to predict the flame spreading of materials using the experimental data from cone calorimeter. Numerical prediction of the flame front position and flame sprea...

The thermonuclear explosion of a massive white dwarf in a Type Ia supernova explosion is characterized by vastly disparate spatial and temporal scales. The extreme dynamic range inherent to the problem prevents the use of direct numerical simulation and forces modelers to resort to subgrid models to describe physical processes taking place on unresolved scales. We consider the evolution of a mo...

Preface In 2005 Norway nominated the brominated flame retardant commercial pentabromodiphenylether (c-PentaBDE) as a persistant organic pollutant (POP) to be evaluated for inclusion in the Stockholm Convention. Based on its Risk Profile developed in 2006 and its Risk Management Evaluation Report developed in 2007, the POPs Review Committee (POPRC) concluded that global action on c-PentaBDE is w...

The study of premixed laminar flames is a central question in combustion theory. Here the differential equations describing steady flame propagation are investigated mathematically. The emphasis is on analytic results, hence a simple model, a onestep exothermic reaction with linear or radiative heat loss is studied. The equations governing our model can be considered as travelling wave equation...

Microgravity experiments were conducted in the 2.2-s drop-tower facility at the NASA Glenn Research Center to study the transient response of the burner-generated spherical diffusion flame caused by its initial displacement from the steady-state position. The experiment involved issuing H2/CH4/inert mixtures of constant fuel mass flow rates from a bronze, porous, 1.27-cm-diameter, spherical bur...

A computational study was conducted on expanding spherical premixed flames to investigate the dynamics of flame-ball formation at elevated temperatures and pressures. Lean H2/air mixtures were investigated using a time-dependent, spherically symmetric code with detailed chemistry, transport, and radiation submodels. Results show that, with increasing pressure, both the steady-state flame-ball r...

The problem of flame propagation in imperfectly premixed mixtures—mixtures of reactants with variable composition—is considered in this numerical study. We carry out two-dimensional direct numerical simulations of a flame propagating in a globally lean fuel-oxidizer mixture with imposed velocity and composition fluctuations of various intensities. The configuration adopted is that of a flame fr...

Large eddy simulation of a three-dimensional spatially developing transitional free methane non-premixed flame is performed. The solver of the governing equations is based upon a projection method. The Smagorinsky model is utilized for the turbulent subgrid scale terms. A global reaction mechanism is applied for the simulation of methane/air combustion. Simulation results clearly illustrate the...

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...

The effects of testosterone (T4) and dihydrotestosterone (DHT) on the survival of the helminth cestode parasite Taenia crassiceps, as well as their effects on actin, tubulin and myosin expression and their assembly into the excretory system of flame cells are described in this paper. In vitro evaluations on parasite viability, flow cytometry, confocal microscopy, video-microscopy of live flame ...