冲压燃烧室V型燃料喷射结构的分离涡模拟

Detached eddy simulation of V-shape arrangement injection holes in ramjet chamber

关键词:  火箭发动机  冲压喷气发动机  燃烧  分离涡模拟+  射流  燃烧效率

Key words:  Rocket engine  Ramjet engine  Combustion  Detached eddy simulation+  Jet flow  Combustion efficiency

摘要:

液态燃料的喷注方式会显著影响火箭基组合循环(RBCC)发动机燃烧室的火焰组织与燃烧效率。通过湍流流动的分离涡模拟,数值计算了RBCC燃烧室液态煤油喷雾燃烧的三维两相流动,并提出了采用V型阵列结构的喷孔空间组合形式,研究结果表明,V型喷孔排列结构,消除了侧壁液态燃料蒸发对值班火焰所带来的消极影响,并通过调整不同喷孔流量,强化了中间喷孔射流形成的值班火焰,相对于直线喷排,可拓宽火焰稳定阈值,提高燃料的蒸发效率与燃烧效率。

Abstract:

The method of liquid fuel injection has significantly influence on the combustion efficiency.The detached eddy simulation numerical method is used to investigate the combustion in Rocket Based Combined Cycle(RBCC) engine.V-shape arrangement injection holes were proposed.The analytical results show that the evaporation process of liquid kerosene injected from holes near the side wall of the chamber could cause negative effect on the stability of flame when the injection holes range in a line.The V-shape arrangement injection holes could suppress this effect,strengthen the flame caused by the injected fuel from the central holes,improve combustion efficiency and provide better lean flame holding performance.