A novel variable geometry flame-holder(VGF) based on V-gutter was presented.The structural characteristics of the flame holder were introduced.Experimental study on drag characteristics of the VGF on un-burning and bu...A novel variable geometry flame-holder(VGF) based on V-gutter was presented.The structural characteristics of the flame holder were introduced.Experimental study on drag characteristics of the VGF on un-burning and burning states was conducted in a rectangular combustion test rig.The influence of the change of gutter trailing edge width w on pressure recovery in different operating conditions was analyzed emphatically.Furthermore,drag characteristics in different trailing edge width variation modes were discussed.Results show that:(1) Narrowing w can observably raise the total pressure recovery σ but the highest σ is not obtained at minimum w.(2) The relationship of drag coefficient ψ and w in the un-burning conditions can be well expressed in a form of exponential equation(w/d>0.4).(3) Drag characteristics are not sensitive to the variation modes and speeds of w.(4) In the burning condition,σ decreases with the increasing of w basically and the course can be divided into three stages.The results and experimental data presented in this paper would enhance the phenomenological understanding of this type of VGF,and would contribute to the next experimental study and numerical calculus of this novel VGF.展开更多
Compact flame-holders for afterburners are an increasing requirement for modern aero engines.However,flame-holder design is non-trivial since high inlet temperatures,velocities,and elaborate structures induce complex ...Compact flame-holders for afterburners are an increasing requirement for modern aero engines.However,flame-holder design is non-trivial since high inlet temperatures,velocities,and elaborate structures induce complex turbulence,combustion,and spray coupling in modern afterburners.In this work,the LES-pdf and stochastic fields-Lagrangian particle spray methods are used to investigate methane and aviation kerosene combustion structures formed by new-type concave flame-holders.The flow pattern,combustion mode,and flame structure of gaseous and liquid fuel around a concave flame-holder are analyzed,discussed,and compared with experimental results.Results reveal that the flame stability of a concave flame-holder is better than that of the non-concave one.Furthermore,when using liquid fuel,the concave flame-holder forms a stable and compact flame.These results suggest concave flame-holders are a promising design for compact afterburners.展开更多
对涡轮基组合循环（turbine based combined cycle，TBCC）发动机超级燃烧室进行了试验研究．首先设计了超级燃烧室模型及相关的试验系统，并在此基础上开展了不同进口速度系数、温度和油气比下点火特性、贫油熄火特性和燃烧效率等燃烧...对涡轮基组合循环（turbine based combined cycle，TBCC）发动机超级燃烧室进行了试验研究．首先设计了超级燃烧室模型及相关的试验系统，并在此基础上开展了不同进口速度系数、温度和油气比下点火特性、贫油熄火特性和燃烧效率等燃烧室性能的试验研究．研究结果表明：随着内涵进口速度系数（0．10～0．25）的增加，点火当量比先减小后增加，熄火当量比逐渐增加，燃烧效率提高；随着内涵进口温度（573～873K）的增加，点火当量比和熄火当量比减小，燃烧效率提高；随外涵进口速度系数、温度的增加，燃烧效率提高．试验中获得最小点火当量比为0．984，最小熄火当量比为0．6．展开更多
文摘A novel variable geometry flame-holder(VGF) based on V-gutter was presented.The structural characteristics of the flame holder were introduced.Experimental study on drag characteristics of the VGF on un-burning and burning states was conducted in a rectangular combustion test rig.The influence of the change of gutter trailing edge width w on pressure recovery in different operating conditions was analyzed emphatically.Furthermore,drag characteristics in different trailing edge width variation modes were discussed.Results show that:(1) Narrowing w can observably raise the total pressure recovery σ but the highest σ is not obtained at minimum w.(2) The relationship of drag coefficient ψ and w in the un-burning conditions can be well expressed in a form of exponential equation(w/d>0.4).(3) Drag characteristics are not sensitive to the variation modes and speeds of w.(4) In the burning condition,σ decreases with the increasing of w basically and the course can be divided into three stages.The results and experimental data presented in this paper would enhance the phenomenological understanding of this type of VGF,and would contribute to the next experimental study and numerical calculus of this novel VGF.
基金National Science and Technology Major Project (2017-Ⅰ-0004-0005)National Natural Science Foundation of China (91741125)。
文摘Compact flame-holders for afterburners are an increasing requirement for modern aero engines.However,flame-holder design is non-trivial since high inlet temperatures,velocities,and elaborate structures induce complex turbulence,combustion,and spray coupling in modern afterburners.In this work,the LES-pdf and stochastic fields-Lagrangian particle spray methods are used to investigate methane and aviation kerosene combustion structures formed by new-type concave flame-holders.The flow pattern,combustion mode,and flame structure of gaseous and liquid fuel around a concave flame-holder are analyzed,discussed,and compared with experimental results.Results reveal that the flame stability of a concave flame-holder is better than that of the non-concave one.Furthermore,when using liquid fuel,the concave flame-holder forms a stable and compact flame.These results suggest concave flame-holders are a promising design for compact afterburners.
文摘对涡轮基组合循环（turbine based combined cycle，TBCC）发动机超级燃烧室进行了试验研究．首先设计了超级燃烧室模型及相关的试验系统，并在此基础上开展了不同进口速度系数、温度和油气比下点火特性、贫油熄火特性和燃烧效率等燃烧室性能的试验研究．研究结果表明：随着内涵进口速度系数（0．10～0．25）的增加，点火当量比先减小后增加，熄火当量比逐渐增加，燃烧效率提高；随着内涵进口温度（573～873K）的增加，点火当量比和熄火当量比减小，燃烧效率提高；随外涵进口速度系数、温度的增加，燃烧效率提高．试验中获得最小点火当量比为0．984，最小熄火当量比为0．6．
