Open Access
ARTICLE
EFFECT OF WALL THERMAL CONDUCTIVITY ON MICRO-SCALE COMBUSTION CHARACTERISTICS OF HYDROGEN-AIR MIXTURES WITH DETAILED CHEMICAL KINETIC MECHANISMS IN Pt/γ-Al2O3 CATALYTIC MICRO-COMBUSTORS
Junjie Chen*, Longfei Yan, Wenya Song
School of Mechanical and Power Engineering, Henan Polytechnic University, Jiaozuo, Henan, 454000, China
* Corresponding Author: Email:
Frontiers in Heat and Mass Transfer 2014, 5, 1-6. https://doi.org/10.5098/hmt.5.16
Abstract
To understand the effect of different thermal conductivities on catalytic combustion characteristics, effect of thermal conductivity on micro-combustion
characteristics of hydrogen-air mixtures in Pt/γ-Al
2O
3 catalytic micro-combustors were investigated numerically with detailed chemical kinetics
mechanisms. Three kinds of wall materials (100, 7.5, and 0.5 W/m·K) were selected to investigate the effect of heat conduction on the catalytic
combustion. The simulation results indicate that the catalytic reaction restrains the gas phase reaction in Pt/γ-Al
2O
3 catalytic micro-combustors. The
gas phase reaction restrained by Pt/γ-Al
2O
3 catalysts is sensitive to thermal boundary condition at the wall. For most conditions, the gas phase reaction
cannot be ignored in Pt/γ-Al
2O
3 catalytic micro-combustors. For low thermal conductivity, the higher temperature gradient on the wall will promote
the gas phase reaction shift upstream; high temperature gradient exists on the wall, and the hot spot can cause the material to melt or degrade the
catalyst. Due to the gas phase reaction is ignited and sustained in micro-combustors by the heat from the catalytic reaction, the effect of thermal
conductivity on micro-scale combustion characteristics is not as obvious as it is in micro-combustors without Pt/γ-Al
2O
3 catalysts.
Keywords
Cite This Article
Chen, J., Yan, L., Song, W. (2014). EFFECT OF WALL THERMAL CONDUCTIVITY ON MICRO-SCALE COMBUSTION CHARACTERISTICS OF HYDROGEN-AIR MIXTURES WITH DETAILED CHEMICAL KINETIC MECHANISMS IN Pt/γ-Al
2O
3 CATALYTIC MICRO-COMBUSTORS.
Frontiers in Heat and Mass Transfer, 5(1), 1–6. https://doi.org/10.5098/hmt.5.16