Numerical simulation of preheating fuel gas combustion in micro-scale tube
Cui Qiang,Yang Weijuan,Wang Yang,Zhou Junhu,Huang Zhenyu,Cen Kefa (State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027, China)
The stability of micro-scale combustion is one of the keys to micro-scale energy power system and equipment. The effects of preheating mixture and flow rate were investigated in a straight-tube shape micro-combustor. The performances of combustor were compared at different preheating temperature and different flow rate of the mixture gases. The flow rates of the fuel gas were 0.16, 0.28, 0.32 L/min respectively and the preheating temperatures were environmental temperature (23 ℃), 250, 500 ℃ respectively. Numerical simulation was used to investigate the combustion process in the combustor. The simulation results indicated that the peak temperature in the reaction region increased and the wall temperature changed little and the heat loss reduced relatively with preheating temperature when flow rate remained unchanged. It was helpful for burning stably. The peak temperature in the reaction region increased with the flow rate when preheating temperature remained unchanged. The outer temperature of micro-combustor was influenced by flow rate seriously. It proves that the proper preheating could increase the reaction temperature and improve the stability, thus inhibits thermal extinction.