The Effects of Radiation on the Thermal-Diffusive Stability Boundaries of Premixed Flames

Abstract

We examine the stability of premixed flames in mixtures containing significant amounts of fine inert dust whose sole impact is upon the radiative transport. By using well-established modeling strategies together with a simple radiation model which preserves much of the essential physics, it is possible to explore to what extent radiative transport displaces the classical non-hydrodynamical stability boundaries of the plane deflagration. Analysis is possible for arbitrary values of both the Planck length and the Boltzman number. It is shown that the pulsating/traveling-wave instability is strongly enhanced by the presence of radiation, and can be present even if Le < 1. On the other hand, radiation tends to suppress the cellular instability normally associated with values of Le less than 1. The latter is consistent with preliminary experimental observations of Abbud-Madrid and Ronney.

Key Words:

• Deflagrations
• radiation
• stability