Optimizing thermal performance of a premixed hydrogen/air fueled micro-combustor with baffles

Abstract

The micro-combustor serves as a critical component in the micro-thermal photovoltaic system (MTPV). In this study, a novel premixed hydrogen/air fueled micro-combustor with baffles was proposed to enhance thermal performance, including average wall temperature, theorical radiation efficiency, and wall temperature uniformity. The key parameters of baffles, including materials, quantity, length, thickness, and layout were optimized. The findings reveal that the introduction of baffles with stainless steel materials led to a noticeable rise in average wall temperature by approximately 150 K, along with a more uniform wall temperature distribution. When considering the materials for the combustion chamber and baffles, stainless steel, alumina ceramics, silicon carbide, and quartz were evaluated. Among these options, stainless steel exhibits the highest average wall temperature and theorical radiation efficiency, while silicon carbide displays the most uniform wall temperature. Upon being outfitted with three stainless steel baffles, each with a length of 13.5 mm and a thickness of 0.3 mm, the micro-combustor achieved optimal thermal performance. It is worth noting that even greater improvements in average wall temperature, theoretical radiation efficiency, and uniformity can be achieved by implementing a well-suited clustered layout for these three baffles.

Keywords

micro-thermal photovoltaic system / micro-combustor / thermal performance / baffle optimization

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