The characteristics of pure heterogeneous reaction for H2/Air mixture in the micro-combustors with different thermophysical properties

Abstract

This paper investigated the characteristics of pure heterogeneous reaction for H2/Air mixture under different wall thermophysical conditions namely; thermal conductivity, convective heat transfer and thermal capacity. The phenomena of pure heterogeneous reaction were observed by OH Planar Laser induced Fluorescence (OH-PLIF) to determine the working conditions. (3D)-models were built to numerically study the effects of different wall thermophysical conditions. The results show that lower thermal conductivity and convective heat transfer coefficient is beneficial to enhancing heterogeneous reaction and improve conversion rate of H2 as less heat is dissipated. The greater thermal capacity has beneficial impact on the reaction stability when the boundary condition changes, but no effect under the steady state. The performance of thermal conduction and convection were comprehensively considered to study the influence and proportion of each on the heterogeneous reaction. Higher thermal resistance can improve the reaction efficiency, reaction stability and reduce application cost. The influence of thermal conduction is greater than that of convective heat transfer.