This paper compares numerical simulations with experiments to study the deformation of lean premixed spherically expanding flames under a negative direct current (DC) electric field. The experiments, including the flame deformation and the ionic distribution on the flame surface were investigated in a mesh to mesh electric field. Besides, a numerical model of adding an electric body force to th...

A large eddy simulation (LES) model was developed to simulate the combustion process in a spark-assisted homogeneous charge compression ignition (SACI) engine. First, an ignition and flame propagation model based on a reaction progress variable is presented. The reaction progress variable is defined based on the normalized cumulative heat release. Transport equation for the progress variable is...

The flashback or propagation of premixed flames along the near-wall low-velocity region at the base of a laminar boundary layer of a reactive mixture has been studied numerically. The analysis, carried out using the constant density approximation for an Arrhenius overall reaction, accounts for the effects of the Lewis number of the fuel. The flow field, as seen by an observer moving with the fr...

Suitability of the Sauter mean diameter and the surface-area mean diameter for representing the ignition and combustor behavior of polydisperse sprays is examined. Initial size distributions considered are the Nukiyama-Tanasawa distribution and a bidisperse spray. Two physical situations are analyzed. In the first, the ignition characteristics of a polydisperse spray in the viscinity of a hot w...

Solid energetic composites have been used and studied in standard air environments, yet the contribution of atmospheric oxygen to reactive material combustion has not been investigated. This study experimentally examines the effect of atmospheric oxygen concentration (4% or 93% oxygen) on energy propagation of nanometric aluminum with copper oxide (Al + CuO), iron oxide (Al + Fe2O3), calcium io...

This analysis addresses the propagation of spiral edge flames found in von Kármán swirling flows induced in rotating porous-disk burners. In this configuration, a porous disk is spun at a constant angular velocity in an otherwise quiescent oxidizing atmosphere. Gaseous methane is injected through the disk pores and burns in a flat diffusion flame adjacent to the disk. Among other flame patterns...

We describe flame propagation between two opposed reactive streams which may differ in their composition and temperature. A two-dimensional counterflow configuration and an irreversible Arrhenius reaction are adopted, along with the constant density approximation. Attention is focused on the influence of two nondimensional parameters. The first one, denoted by g, represents the difference in th...

We present an asymptotic study of triple-flames in a strained mixing layer under a reversible reaction, which extends analytical descriptions of these flames beyond the common framework of a single irreversible Arrhenius reaction and constitutes a first step towards accounting for real chemistry effects. The study is carried out in the twodimensional counterflow configuration and adopts a const...

We consider the competition of the different physical processes that can affect the evolution of a flame bubble in a Type Ia supernovae — burning, turbulence and buoyancy. Even in the vigorously turbulent conditions of a convecting white dwarf, thermonuclear burning that begins at a point near the center (within 100 km) of the star is dominated by the spherical laminar expansion of the flame, u...

This paper compares the values of the thermal and fire resistance properties of composites made using the hand layup technique. E-Glass fiber reinforced epoxy composites was fabricated by filling varying concentration of aluminum oxide (Al2O3), magnesium hydroxide(Mg(OH)2), silicon carbide (SiC), and hematite powder. The main aim of this work was to determine the thermal conductivity, thermal e...