Numerical study of effect of wall parameters on catalytic combustion characteristics of CH4/air in a heat recirculation micro-combustor

Thermal management and catalytic combustion stability characteristics of premixed methane/air in heat recirculation meso-combustors

“…19,20 Jiang et al 21,22 investigated the influence of the baffle height on entropy generation distribution in heat recirculation micro-combustors. [34][35][36][37][38][39][40] The wall serves for axial heat conduction and heat losses which plays a significant role in the thermal management in the catalytic micro-combustors/ meso-combustors. Recently, Fan 15,23 found that flame blow-off limit for very lean CH 4 /air mixtures was obviously extended in the micro-combustor with preheating channels.…”

“…Further research demonstrated that solid material with high thermal conductivity and small emissivity was suggested to extend flame blow-off limit. [38][39][40] Nevertheless, very few attentions focus on revealing combustion stability mechanism in the heat recirculation catalytic micro-combustors/ meso-combustors, especially for low burning fuels, such as methane. [24][25][26] The flame stability is enhanced by faster heat conduction and radiant heat exchange of porous media.…”

“…Indeed, proper thermal and flow management in the design of catalytic micro-combustors/meso-combustors have been proved to be the key issues in recent researches. [34][35][36][37][38][39][40] The wall serves for axial heat conduction and heat losses which plays a significant role in the thermal management in the catalytic micro-combustors/ meso-combustors. Kaisare et al 34 verified that the choice of wall thermal conductivity to obtain wider stability limits depends on flow velocities.…”

“…36,37 Notably, heat recirculation micro-/meso-combustors which have been proved to promote combustion efficiency and extend stability limits in the homogeneous flame 21-23 still favor catalytic pathway. [38][39][40] Nevertheless, very few attentions focus on revealing combustion stability mechanism in the heat recirculation catalytic micro-combustors/ meso-combustors, especially for low burning fuels, such as methane. It is noteworthy that, for such micro-/mesocombustors, the inner wall (baffles) will serve as a more important role in combustion stability and fuel conversion.…”

Experimental study on the influence of wall heat effect on gas explosion and its propagation

“…Yunfei Yan et al carried out the numerical study on influence of wall parameters on catalytic combustion characteristics of CH4/air in a heat recirculation micro-combustor, their results show that with the decrease in thermal conductivity of wall materials, the temperature of the reaction region increases and hot spots becomes more obvious [3] . The effect of thermal radiation on the dynamics of a thermal explosion of a flammable gas mixture was studied, it was pointed out that the effects of thermal radiation can be significant, especially at high temperatures, and cannot be ignored in the analysis of this phenomenon [4] .The material thermal characteristics also have influence on explosion parameters [5] .…”