关键词: 凹槽;横向喷射;回流区;总压损失;推力增益;穿透深度

Abstract: Effects of transverse injection from bottom wall of a series of shallow cavity with the same length and different depth on flow field and combustion characteristics of supersonic combustor in altitude 30km, flying Mach number 6, under the condition with or without chemical reactions were simulated. Comparison with traditional wall transverse injection was carried out. It is found that introducing shallow cavity can effectively weaken shock system of flow field and obviously reduce total pressure loss of combustion flow field. Subsonic recirculation zone formed between the front wall of cavity and fuel jet column can strengthen mixing and achieve flame-holding and this effect will be more obvious with increasing depth of cavity.Employing shallow cavity can reduce transverse jet penetration depth, resulting in the decrease of combustion coefficient to a certain extent.

Key words: Cavity; Transverse injection; Recirculation zone; Total pressure loss; Thrust gain; Penetration depth