Chain-Branching Explosions in Mixing Layers

Chain-Branching Explosions in Mixing Layers

The chain-branching process leading to ignition in the high-temperature hydrogenoxygen mixing layer is studied by application of a novel WKB-like method when, as is typically the case, two branching radicals cannot be assumed to maintain steady state. It is shown that the initiation reactions, responsible for the early radical buildup, cease being important when the radical mass fractions reach...

Branched-chain ignition in strained mixing layers

The time-dependent evolution of the radical pool in an initially inert hydrogen-air counterflow mixing layer subject to variable strain is investigated analytically. Although the initial chemistry description contains three different chain carriers, namely, H, O and OH, it is shown that the ignition problem can be accurately described in terms of a single radical-pool variable that incorporates...

Homogeneous Branched-Chain Explosions

A model of homogeneous explosions with competing branching and recombination processes due to Kapila is analyzed by singular perturbation methods. In this model, the concentration of radicals is very low during a long induction period that ends with a rapid radical-growth stage in which all the reactants are consumed as the radicals reach their peak concentrations. The sudden jump in radical co...

On Explosions in Heavy - Tailed Branching Random Walks

Consider a branching random walk on R, with offspring distribution Z and nonnegative displacement distribution W . We say that explosion occurs if an infinite number of particles may be found within a finite distance of the origin. In this paper, we investigate this phenomenon when the offspring distribution Z is heavy-tailed. Under an appropriate condition, we are able to characterize the pair...

Effect of Merging Angle on Turbulent Mixing Layers