火焰筒壁高温区与近壁区流场的数值模拟研究

航空发动机火焰筒的大孔包括主燃孔和掺混孔,将多斜孔壁冷却方式应用到真实环形燃烧室的火焰筒壁上,运用CFD软件,通过数值模拟的方式,计算研究整个燃烧室的温度分布,特别考虑了火焰筒壁温的分布,对近壁区的流场进行计算研究。研究分析表明:内外环壁热侧大部分区域温度都保持在1 000 K～1 100 K,在材料的长期许用温度范围内;同时针对外环壁主燃孔和掺混孔附近的局部高温点,提出冷却方案,改善了近壁区的流场分布,对改善高温点起到了很好的效果,最大幅度降低达13.2%,壁面温度更加均匀,对降低热应力水平,延长火焰筒使用寿命有利。

Study on High Temperature Regions of Annular Flame Tube and Flow Field of Near Wall Regions

The big holes of Aero-engine combustor liner include primary holes and dilution holes,this paper applied the effusion-cooling method into the real annular flame tube.With the help of the CFD software,numerical simulation was carried out to investigate on the temperature distribution of the whole combustor,especially of the liners,including flow fields of near wall regions.The result shows that the temperature of most regions of outer and inner liners on the hot side is from 1 000 K to 1 100 K,which is in the material′s long-term allowable temperature range.And cooling scheme was put forward considered on hot spots behind the primary holes and dilution holes on the outer liner,which changed the flow of the near wall regions,and effectively improved the hot spots.The most decreasing range of the highest temperature is 13.2%,and more uniform wall temperature makes thermal stress level reduced and the service life of flame tubes extended.