Our objective is to characterize gravity effects on the structure of laminar methane–air partially premixed flames through detailed simulations. We examine the heat loss due to radiation from similar flames that are established at various gravitational accelerations and coflow velocities. Radiation is modeled using the optically thin assumption that provides a limiting value for the radiation h...

Phosphorus-based flame retardants were incorporated into different, easily preparable matrices, such as polymeric thermoset resins and paraffin as a proposed model for polyolefins and investigated for their flame retardancy performance. The favored mode of action of each flame retardant was identified in each respective system and at each respective concentration. Thermogravimetric analysis was...

This work focuses upon the effects of DC electric fields on the stability of downward propagating atmospheric pressure premixed propane–air flames under experimental conditions that provide close coupling of the electric field to the flame. With the appropriate electrode geometry, modest applied voltages are shown to drive a stable conical flame first into a wrinkled-laminar flamelet geometry, ...

Large eddy simulations in a wall bounded domain are conducted in order to study the kinematic structure of premixed turbulent flame. The linear model presents a prospect of isolating the effects of each of the physical mechanisms that underly turbulent combustion. In the present study, we investigate the flame structure in the absence of thermodyamic effects such as heat release using this mode...

Simultaneous planar laser-induced incandescence, hydroxyl radical planar laser-induced fluorescence, and droplet Mie scattering are used to study the instantaneous flame structure and soot formation process in an atmospheric pressure, swirl-stabilized, liquid-fueled, model gas-turbine combustor. Optimal excitation and detection schemes to maximize single-shot signals and avoid interferences fro...

At a density near a few ×10 g cm, the subsonic burning in a Type Ia supernova enters the distributed regime (high Karlovitz number). In this regime, turbulence disrupts the internal structure of the flame, and so the idea of laminar burning propagated by conduction is no longer valid. The nature of the burning in this distributed regime depends on the turbulent Damköhler number (DaT ), which st...

Vertically well-aligned multi-walled carbon nanotubes (MWNTs) with uniform diameters ( 15 nm) were grown on catalytic probes at high yield rates in an inverse diffusion flame (IDF) of a co-flow jet configuration using methane as fuel. Varied parameters investigated included: alloy composition (e.g. Fe, Ni/Cu, Ni/Cr/Fe), sampling positions within the flame structure, and voltage bias applied to ...