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通过调节燃料氢喷射压力参数从而改变油气当量比,分别在冷态喷流与燃烧情况下计算了当量比对流场波系及燃料与空气的掺混、燃烧特性的影响.研究表明:增大当量比会增大燃烧反压,扩大上游边界层分离区,逐渐将激波串推向燃烧室进口;同时发现燃料与空气的混合性能在近场处受当量比影响较大,随当量比增大混合效果明显增强,而在远场处基本不再受当量比变化的影响;增大当量比一定程度增大射流穿透深度,但并不能明显改善燃料分布区不合理问题,导致燃烧效率随当量比单调下降;流场总压损失及凹腔阻力系数均同当量比成正比例关系,而流场摩擦阻力随当量比单调下降,且燃烧使摩擦阻力更小.
By adjusting the fuel injection pressure of hydrogen to change the equivalence ratio of oil and gas, the effects of equivalence ratio on the flow field, fuel and air blending and combustion characteristics were calculated under cold jet and combustion respectively. Equivalent ratio will increase the combustion back pressure, expanding the upper boundary layer separation zone, and gradually push the shock wave train to the combustion chamber inlet; also found that the mixing performance of fuel and air in the near field by the equivalent ratio greater impact, with the equivalent ratio increase Large mixing effect is obviously enhanced, but in the far field is no longer subject to changes in equivalence ratio; increasing the equivalence ratio to some extent, increasing the jet penetration depth, but does not significantly improve the fuel distribution area unreasonable problems, resulting in combustion efficiency with The equivalent ratio drops monotonically; the total pressure loss in the flow field and the cavitation resistance coefficient are proportional to the equivalent ratio, while the frictional resistance in the flow field decreases monotonically with the equivalence ratio, and the friction makes the friction smaller.