Gasification of a condensed material in a hot gas

Abstract

A theoretical analysis is presented for the gasification process of a condensed materials suddenly exposed to a hot stagnant gas. When the gasification rate is given by an Arrhenius law the surface temperature rises to the non-gasification jump value upon contact with the hot gases. The convective effect due to surface regression and gasification flow, plus the energy absorbed by the gasification causes the surface temperature to decrease with time. An analytical description of the surface temperature and concentration history is presented, together with closed form expressions for the temperature and concentration profiles for small and large times. A closed form analytical description is also given for the gasification process under surface equilibrium "Clasiu Clapeyron" conditions. In this case the surface temperature remains at a constant jump value, and the temperature and concentration profiles have a similarity form.