新型沙丘形突扩燃烧室三维冷态迎风角度研究

Research of Windward Angle of A New Dune-shaped Dump Combustor

对沙丘形突扩燃烧室而言,适当的迎风角度能够保证沙丘的低阻特性并得到稳定的回流区。文中采用Realizable k-ε湍流模型和二阶差分格式对该燃烧室内部流场进行了数值模拟,详细分析了冷态条件下,当突扩比和背风角度一定时,不同迎风角度（0~70°）下沙丘突扩燃烧室内的流动特性,并总结了迎风角度对流场的影响规律,结果表明：迎风角度40°时,燃烧室总压损失小、回流区流动稳定且形状均匀饱满,燃烧室综合性能达到最优。

As for dune-shaped dump combustion, proper windward angle can ensure low resistance characteristics of the dune and obtain stable recirculation zone. The internal flow field of this combustion chamber was simulated by Realizable k-εturbulence model and second-order difference scheme. In this paper, the cold flow characteristics of different windward angle （0~70°） were analyzed under the certain leeward angle and sudden expansion ratio of the dune-shaped burners. The influence laws of different windward angle on the flow field were summarized. According to calculating results, when windward angle is 40°, combustor suffers less in total pressure loss, the flow recircula-tion zone is stable, and its comprehensive performance achieves best.