Numerical investigation of optimal geometry parameters for ejectors of premixed burner
来源期刊:中南大学学报(英文版)2014年第3期
论文作者:LIU Feng-guo(刘凤国) 张蕊 刘文博 Zhai Jun(翟军) ZHENG Bin(郑斌)
文章页码:1011 - 1016
Key words:ejector; computational fluid dynamics (CFD); burner; distribution orifice; premixed combustion
Abstract: An ejector of low NOx burner was designed for a gas instantaneous water heater in this work. The flowing and mixing process of the ejector was investigated by computational fluid dynamics (CFD) approach. A comprehensive study was conducted to understand the effects of the geometrical parameters on the static pressure of air and methane, and mole fraction uniformity of methane at the outlet of ejector. The distribution chamber was applied to balance the pressure and improve the mixing process of methane and air in front of the fire hole. A distribution orifice plate with seven distribution orifices was introduced at the outlet of the ejector to improve the flow organization. It is found that the nozzle exit position of 5 mm and nozzle diameter d >1.3 mm should be used to improve the flow organization and realize the well premixed combustion for this designed ejector.
LIU Feng-guo(刘凤国)1, ZHANG Rui(张蕊)1, LIU Wen-bo(刘文博)2, Zhai Jun(翟军)2, ZHENG Bin(郑斌)1
(1. School of Energy and Safety Engineering, Tianjin Chengjian University 300384, China;
2. China Quality Supervising Engineering and Test Center for Gas Appliances (CGAC),
Tianjin 300384, China)
Abstract:An ejector of low NOx burner was designed for a gas instantaneous water heater in this work. The flowing and mixing process of the ejector was investigated by computational fluid dynamics (CFD) approach. A comprehensive study was conducted to understand the effects of the geometrical parameters on the static pressure of air and methane, and mole fraction uniformity of methane at the outlet of ejector. The distribution chamber was applied to balance the pressure and improve the mixing process of methane and air in front of the fire hole. A distribution orifice plate with seven distribution orifices was introduced at the outlet of the ejector to improve the flow organization. It is found that the nozzle exit position of 5 mm and nozzle diameter d >1.3 mm should be used to improve the flow organization and realize the well premixed combustion for this designed ejector.
Key words:ejector; computational fluid dynamics (CFD); burner; distribution orifice; premixed combustion