分流技术强化超声速混合及燃烧的数值模拟

本文提出一个利用分流技术强化超声速横侧射流混合及燃烧的新方法,即通过一个细小通道连通燃料喷口上下游,上游高压流体部分分流到下游,从底部抬高燃料穿透深度.应用修正可压缩性的 k-ε湍流模型,对不同喷射压力下冷态及燃烧流场进行数值模拟.有无采用分流技术的结果对比表明,分流技术能有效增大混合效率和燃烧效率,分流孔位置是一重要影响因素.观察到两类强化混合及燃烧的机制,合理布置分流孔位置可使燃烧效率相对提高 25% 以上.

NUMERICAL INVESTIGATION OF MIXING AND COMBUSTION ENHANCEMENT BY SHUNTING IN SUPERSONIC FLOWS

This paper proposes a new method of mixing and combustion enhancement utilizing shunting technology in supersonic flow with transverse injection, viz. to connect the upstream and downstream areas of the fuel inlet through a small channel vent. Part of higher-pressure fluid upstream shunts into downstream area and elevates fuel penetration depth from the bottom. Numerical simulations of cold and combustion flow field under different injection pressures are performed applying the k - ε turbulence model with compressibility modification. The results of comparisons with and without shunting show that shunting technology can effectively increase the mixing and combustion efficiency and the locations of shunting holes is an important factor. Two types of mixing and combustion enhancement mechanism are observed. The combustion efficiency can be increased by 25% above relatively when the shunting holes are arranged reasonably.