Numerical simulation of micro-scale catalytic combustion characteristics with detailed chemical kinetic reaction mechanisms of hydrogen/air

作者：Chen Junjie^*; Yan Longfei; Song Wenya

来源：Reaction Kinetics, Mechanisms and Catalysis, 2014, 113(1): 19-37.

DOI：10.1007/s11144-014-0719-x

• Catalytic combustion
• Combustion characteristics
• Micro-combustion
• Reaction mechanisms
• Thermal conductivity

Micro-scale catalytic combustion characteristics with detailed gas phase and surface catalytic reaction mechanisms of hydrogen/air were investigated numerically. Micro-combustion characteristics for different reaction models and the influence of wall thermal conductivity, inlet velocity, tube diameter on surface catalytic combustion reaction were discussed. The computational results indicate that the surface catalytic combustion restrains the gas phase combustion. The gas phase reaction inhibition by the catalyst is sensitive to thermal boundary condition at the wall. The gas phase reaction cannot be ignored inside a micro-scale catalyst combustor for most conditions. The higher wall temperature gradient for low wall thermal conductivity will promote the gas phase combustion shift upstream and will result in a higher temperature distribution. The micro-tube can be divided into two regions. The upstream region is dominated by the surface catalytic reaction and the downstream region is dominated by the gas phase combustion. With increasing inlet velocity, the region dominated by surface catalytic reactions expanded downstream and finally occupied the whole micro-tube. The temperature of the flame core decreases with the decrease of tube diameter. Decreasing the tube diameter will enhance the surface catalytic reactions. Inside a micro-catalytic combustor, the effect of surface catalytic reaction on gas phase reaction can be divided into three characteristic reaction types.

• 出版日期2014-10
• 单位河南理工大学