核心机驱动风扇级的气动设计特点分析

Analysis of aerodynamic design characteristics of core driven fan stage

以某核心机驱动风扇级(core driven fan stage,简称CDFS)的气动方案为例,使用新版Denton程序通过数值模拟分析了CDFS的内部流动特点和关键设计参数的影响,总结了CDFS气动设计上的特点和难点:①CDFS需要采用进口可调导叶实现工作模式的转换;②叶尖切线速度和气动负荷不匹配是CDFS难以获得高效率的主要原因;③进口可调导叶出口气流角分布和调节方式对CDFS的性能有重要影响;④CDFS转子气动设计的难点是控制单外涵模式下的激波损失;⑤CDFS静子气动设计的难点在于两种工作模式下其进口气流角的分布和幅值均发生了较大变化.

The flow field and aerodynamic design characteristics of core driven fan stage （CDFS） were simulated and analyzed with modified Denton code. The results show that： 1） adjustable inlet guide vane （IGV） is needed to achieve the switch of different working modes; 2） the conflict between high tip speed and low aerodynamic loading restrains the efficiency of CDFS; 3） IGV outlet swirl distribution and switch mode have remarkable effects on CDFS performance; 4） the challenge in the aerodynamic design of CDFS rotor is the shock loss in single bypass mode; 5） the change in distribution and magnitude of CDFS stator inlet flow angle is the main challenge in CDFS stator design.