摘要
针对所设计的超燃冲压发动机燃烧室,对液体煤油的凹槽火焰稳定特性进行研究。采用概率密度函数紊流扩散燃烧模型、紊流k-ω模型和离散液滴模型,数值模拟了飞行马赫数为5,不同位置和油气当量比喷射燃料的情况。从凹槽前缘喷射燃料,凹槽在富油时火焰稳定范围比较广;从凹槽底面和后壁喷射燃料,凹槽抑制了富油时火焰稳定范围,而在贫油时火焰稳定范围比较广。火焰结构受燃料喷射位置和油气当量比的影响。油气当量比是3.0时,凹槽出现开放型凹槽流动;而其它的模拟情况,凹槽均出现过渡型凹槽流动,这与冷流时凹槽流动类型不同。深入研究凹槽的热流场特性,使凹槽发挥最大的火焰稳定作用。
Studies were performed to examine the stability of liquid kerosene-fueled flames in cavity flame-holders.The numerical analysis of the kerosene spray supersonic combustion was carried out in the case of the flight Mach number was 5,and the different fuel-air equivalence ratios and different fuel injectors,with the PDF turbulence and chemistry interaction model,k-ω turbulence model and the discrete droplet model.For injected liquid kerosene from leading edge,the cavity has a wide range of stable operations and a large fuel-rich limit.For injection from floor wall and from aft wall,the cavity shows to suppress the fuel-rich blowout limit,to enhance the fuel-lean limit,and the floor wall injection is more than the aft wall injection.The fuel-air equivalence ratio and fuel injection location affect the configuration of flame.As equivalence ratio is 3.0,the open cavity flow occurs for L/D=5.Transitional cavity flow occurs for L/D=5 in other case and is different from the cavity in non-reacting flow.The simulation results demonstrate the cavity characteristics is different in non-reacting and reacting flows,and the conventional definition of cavity flow characteristics based on non-reacting flows needs to be made corrections.
出处
《科学技术与工程》
2011年第29期7168-7173,共6页
Science Technology and Engineering
基金
博士后基金项目资助
