摘要
波瓣混流器是一种典型的燃烧室气体混合装置,某预冷组合发动机燃烧室采用了波瓣混流器进行氢气/空气的掺混组织。为了获得不同波瓣混流器修型结构对氢气/空气的掺混性能的影响,分别采用导流结构和锯齿尾缘对波瓣混流器进行修型。通过开展数值仿真和对热混合效率公式的修正,从流场速度分布、流向涡和正交涡以及性能参数方面进行了掺混特性的对比分析。结果表明:导流结构对流场中回流区的分布具有显著影响,导流结构的平面面积越大,回流区范围越大;回流区范围增大会增加初始位置的内外涵速度差2.4倍到6倍,减小平均流向涡强度,增大平均正交涡强度,进而影响热混合效率,其中圆形导流结构在流动初期提高3%,后期降低5.9%;锯齿尾缘修型降低了热混合效率,其中三角形修型结构降低约2.8%,较其他结构最明显。
Lobe mixer is a typical combustion chamber gas mixing device.A precooling combined engine combustion chamber adopts lobe mixer to mix hydrogen and air.In order to obtain the influence of different modified structures on the hydrogen-air mixing performance of the lobe mixer,based on the hydrogen fuel combustor of a precooled combined engine,the guide structure and sawtooth trailing edge were used to modify the lobe mixer.By carrying out numerical simulation and revising the thermal mixing efficiency formula,a comparative analysis was carried out from the aspects of the velocity distribution of the flow field,the streamwise vortex,the normal vortex,and the performance parameters.The results are as follows:1)The guide structure has an important influence on the distribution of the recirculation zone in the flow field,and the larger the plane area of the guide structure,the larger the recirculation zone;2)The increase of the recirculation zone would increase the velocity difference between the inner and outer culverts at the initial position by up to 6 times,reduced the average streamwise vorticities,increased the average normal vorticities and then affected the mixing performance,which of the circular guide structure increased by 3%at the initial stage and decreased by 5.9%at the later stage of flow.3)The sawtooth trailing edge modified structure reduced the thermal mixing efficiency which of the triangular modified structure reduced by about 2.8%,which was the most obvious than other structures.
作者
吴弈臻
马元
黄乐萍
马文友
王祎
WU Yizhen;MA Yuan;HUANG Leping;MA Wenyou;WANG Yi(Xi'an Aerospace Propulsion Institute,Xi'an 710100,China)
出处
《火箭推进》
CAS
2021年第6期76-85,共10页
Journal of Rocket Propulsion
基金
国家自然科学基金联合基金(U1967203)。
关键词
预冷组合发动机
氢/空气混合
波瓣混流器
修型结构
流向涡
正交涡
热混合效率
precooling combined engine
hydrogen-air mixing
lobe mixer
modified structure
streamwise vortex
normal vortex
thermal mixing efficiency
