Development and temperature measurement of heat-recirculation gas combustors burning methane/air

A novel energy-economic and high efficiency heat recirculation combustor featuring “gas combustor, heat recirculation, and half-closed flame” was developed. The combustor includes three preheated modules, namely lower spiral channel without top cover, lower spiral channel with top cover, and upper spiral channel with top cover. The feed gas was methane and air mixture. The effects of fuel gas Reynolds Number (Rem), equivalent ratio (Φ), and preheat pattern on preheat temperature and flame combustion temperature of the heat recirculation gas combustor were investigated. The result of transient temperature measurement indicated that the preheat temperature increased linearly with combustion time, reaching up to 232.2°C in module C. Preheat pattern can affect mixed gas preheat temperature and flame combustion temperature. Among the three modules, the preheating effect of upper spiral channel with top cover was the best, the lower spiral channel with top cover was the second, and lower spiral channel without top cover module ranked the third.