Effect of thermal conductivity of solid wall on combustion efficiency of a micro-combustor with cavities

摘要: We recently developed a micro cavity-combustor which has strong ability in flame stabilization and is promising to be used power generation apparatus for MEMS propulsion systems. In the present paper, effect of wall thermal conductivity on combustion efficiency lean H2/air was numerically investigated. It shown that decrease due flame-tip opening at high velocity. For convenience quantitative comparison, ‘‘flame-splitting limit’’ defined as critical velocity when drops 80%. very interesting find flame-splitting limit exhibits non-monotonic variation with conductivity. The analysis reveals that, larger conductivity, heat recirculation fresh mixture better, leads higher flow cavity exit; therefore, front suffers stronger stretching splitted lower However, smaller central region far downstream becomes faster, results flame-stretching limit. summary, moderate advantageous achieve efficiency.