3. SIMILARITY OF TEMPERATURE AND CONCENTRATION FIELDS IN FILTRATION COMBUSTION OF GASES
Author: KABILOV M.M. AND GULBOEV B.J. DOWNLOAD
DOI:
Abstract
The paper presents a mathematical model of a stationary wave of filtration combustion of gases, taking into account heat transfer to the surrounding space and diffusion coefficients of the components of the mixture of gases. As a result of the study, relations for the wave velocity in adiabatic and non-adiabatic modes of combustion are obtained, which contain the Lewis numbers of the mixture components, along with other physical and chemical constants of the mixture and porous medium. In the case of absence of heat loss into the surrounding space and intensive interfacial heat exchange, the similarity criteria of temperature and concentration fields are established. Linear dependences of the relative concentration of the mixture components on the dimensionless temperature are obtained. Calculated characteristics of the stationary wave of filtration combustion of hydrogen- and methaneair mixtures at heat loss and its absence have been analysed. The critical velocities of blowing at which the standing wave of combustion and the change of the direction of the wave motion are realised are established. It is argued that at further increase of heat transfer coefficient into the surrounding space the critical velocities will coincide and the change of the wave motion direction
will not occur, since the curves of wave velocity dependence on the blow-in velocity have a parabolic form.
Keywords
similarity criteria, wave velocity, equilibrium temperature, Lewis number, adiabatic regime, non-adiabatic regime, hydrogen-air mixture, methane-air mixture.