Mechanism of Methane-Air Combustion on the Surface of a Porous Ceramic Plate

Abstract

The mechanism of mathane-air combustion on the surface of a porous ceramic plate was studied by experimental testing and analysis of a simplified theoretical model based on one-dimensional flow of methane-air mixture and the overall chemical reaction rate. The effects of such parameters as thickness of porous ceramic plates, equivalence ratio of mixed-gas and heat load on the combustion characteristics were examined. A thicker plate achieves higher surface temperature as premixed gas is preheated on the porous ceramic plate. The combustion zone is closest to the porous ceramic plate with equivalence ratio Φ = 1.2. The surface temperature has peak value at a certain heat load. It is observed that combustion begins just off the porous ceramic plate, and the flame is kept less than 1mm from the surface. The position is influenced by the combustion conditions. These phenomena can be explained by a theoretical model and such aspects of the combustion mechanism as temperature profile of premixed gas and porous plate and chemical reaction on the plate are made clear. © 1993, The Society of Chemical Engineers, Japan. All rights reserved.