Combustion in porous media and its applications--a comprehensive survey.

Recent theoretical advances in premixed gas combustion are reviewed. The attention is focused on (1) self-acceleration of outward propagating wrinkled flames sustained by the intrinsic flame instability, (2) fragmentation of near-limit cellular flames and formation of self-drifting flame balls, (3) flame acceleration and extinction by large-scale turbulence, (4) multiplicity of detonation regimes in hydraulically resisted flows and the phenomenon of shock-free pressure-driven combustion, and (5) hydraulic resistance as a mechanisms of deflagration-to-detonation transition.

Some developments in premixed combustion modeling

Flame acceleration and deflagration-to-detonation transition in micro- and macro-channels: An integrated mechanistic study

Hydraulic resistance as a mechanism for deflagration-to-detonation transition

The role of gas permeation in convective burning

In gas filled porous media the local elevation of pressure slowly diffuses to the adjacent layers of gas inducing the rise in temperature there. In the case of explosive gases this mechanism may lead to the formation of a self-sustaining combustion wave propagating at a constant speed. It is argued that the barodiffusion may be responsible for the occurrence of the so-called high velocity regime often observed in filtration combustion It is shown that the high velocity regime may emanate from the low velocity regime controlled by the sysiem's thermal diffusivity. It is suggested that the effect may be related to the classical problem of deflagration-to-detonation transition in narrow pipes.

On Combustion Waves Driven by Diffusion of Pressure

Drainage effects on shock wave propagating through aqueous foams

In porous media the local elevation of pressure slowly propagates in the adjacent layers of the gas causing the temperature rise there In the presence of explosive gases this mechanism may lead to the formation of self sustaining combustion waves propagating at a constant speed

On creeping detonation in filtration combustion

This paper is focused on the capabilities of gas-liquidfoamstoattenuateacousticwaves.Itispostu- lated that the sound attenuation phenomenon in foams is largely governed by the hydrodynamic resistance of the Plateau-Gibbs channels (PGC) to the flow of liquid through them. It is shown that the addition of solid par- ticles to gas-liquid foams has opposite effects depend- ing on the concentration of the added solid particles. As long as the concentration of the added solid par- ticles is smaller than a certain critical value the sound attenuation coefficient increases and as a result in the sound velocity decreases. However, if the concentration oftheaddedsolidparticlesbecomeslargerthanthiscrit- ical value the attenuation coefficient decreases and the sound velocity increases. When the concentration of the solid particles reaches some critical value, the particles block the Plateau-Gibbs channels and stop the filtra- tion. As a result the attenuation coefficient of the sound wave decreases while the sound velocity, in such three-

Foam self-clarification phenomenon: An experimental investigation

The purpose of the present investigation is to analyze the phenomenon of shock wave formation in foams using the Burgers equation which is derived from the conservation laws for bubbly liquids. It is shown that the ratio of parameters of nonlinearity in the Burgers equation describing wave propagation in bubbly liquids to that in foams is of order 40, while the coefficient of bulk viscosity in foams is by a factor 103 higher than that in bubbly liquids. This explains why oscillatory shock waves are not detected in shock tube experiments with foams while they are observed under similar conditions in bubbly liquids.

I. Shreiber

Papers

On Combustion Waves Driven by Diffusion of Pressure

Drainage effects on shock wave propagating through aqueous foams

On creeping detonation in filtration combustion

Foam self-clarification phenomenon: An experimental investigation

Formation of Shock Waves in Gas-Liquid Foams