On igniting a reacting gas by a heat source of finite heat capacity: PMM vol. 43, no. 1, 1979, pp.75–82

Abstract

The problem of igniting gas by a body of finite heat capacity is solved by the method of joining asymptotic expansions and, also, by numerical methods, taking into account the reagent burnout and variation of heater temperature. The space-time pattern of temperature distribution is determined, and the law of the igniter temperature variation established. Dependence of the ignition time on characteristic parameters of the problem, such as the order of reaction, the Lewis and activation numbers, thermophysical parameters of the heater, etc. is established. It is assumed in the analysis that ignition takes place when the heat flux through the igniter surface becomes zero. Results of numerical solution of the input problem are compared with the approximate analytical determination. It is established that for β = E /( RT 0) of order 20 they differ by not more than 15–20%; with increasing β the difference diminishes.