论文部分内容阅读
针对一种带三维导流型凹槽的煤油超燃冲压发动机,考虑两相(颗粒随机轨道方法)、湍流(Menter的SSTk ω模型)和多步燃烧机理(代用燃料C12H23的17组分30步化学反应机理),对飞行马赫数M0为4和6的典型工况开展了初步数值研究。结果流道壁面压强分布与试验值取得了较好的吻合,不过M0=6工况的第一凹槽组附近的存在约23%的数值误差。给出了误差原因。进一步分析表明(1)M0=6工况的分段燃料喷注对整体燃烧产生了有利影响,导致了较高的燃烧效率。(2)M0=4工况采用了不合理喷注参数,结果煤油穿透深度不足,获得了较低的燃烧效率。(3)三维导流型凹槽附近的湍流效应明显,对掺混产生了有利影响。不过超声速主流的湍流强度远大于亚声速主流情况。
For a kerosene scramjet with three-dimensional flow guide groove, the two-phase (particle randomized orbital method), turbulent flow (Menter’s SSTk ω model) and multi-step combustion mechanism (substitute fuel C12H23 for 17 components in 30 steps Chemical reaction mechanism), a preliminary numerical study of the typical operating conditions of flight Mach number M0 4 and 6 were carried out. As a result, the wall pressure distribution in the runner is in good agreement with the experimental value, but there is about 23% numerical error near the first groove set with M0 = 6. The reason for the error is given. Further analysis showed that (1) segmented fuel injection with M0 = 6 operating conditions had a beneficial effect on overall combustion, resulting in higher combustion efficiency. (2) Unreasonable injection parameters were used for M0 = 4 working condition. As a result, the penetration depth of kerosene was insufficient and a lower combustion efficiency was obtained. (3) The turbulence effect near the three-dimensional diversion groove is obvious, which has a beneficial effect on the blending. However, the intensity of supersonic mainstream turbulence is much larger than the prevailing sub-sonic situation.