Ignition of a radiating gas by an incandescent surface

Abstract

The fundamental regularities of ignition of a radiating and absorbing gas by an incandescent surface are examined. In the case of an optically thin medium characteristic for high-temperature ignition, the problem is solved in the traditional stationary and nonstationary formulations [8]. It is shown that radiant heat transfer plays an essential part in the gas ignition process, in particular, the process can be accelerated and retarded in an optically thin gas medium because of radiant heat exchange. The case of an optically dense gasl kb/l o corresponds to radiant heat conduction, and therefore, does not result in a change in the ignition time but only to an increase in the scale of the lengthl o. For intermediate values ofl kb/l o the dependence of τ✩ on parameters governing the energetics of radiant heat transfer is complex in nature and can only be analyzed numerically in each specific case. The development of a suitable model of radiation heat exchange is the fundamental difficulty here.