摘要
为了考察对转风扇的工程应用性,通过气动方案论证、气动设计技术研究、强度颤振分析研究、声学分析研究、非设计点匹配和调节研究以及进口畸变流场模拟研究,初步探讨民用大涵道比发动机对转风扇的设计技术,总结未来工程应用可能面临的问题以及解决方案。与常规风扇设计相比,对转风扇后排叶片在非设计点下的工作状态变化幅度较大,因此后排叶片的设计攻角选取不能过大。虽然较低的设计转速下转子叶片的振动频率不高,但也不必太过担心颤振问题,本文风扇在设计点并不会出现颤振问题。采用对转技术降低风扇转速是降低噪声的有效手段,本文设计的风扇远场最大声压级只有90dB左右。对转风扇在非设计转速具有较好的性能水平,在工程应用时可以不必调节后排叶片的安装角。对转风扇对进气畸变的衰减作用十分有限,两排转子对转也使得畸变区域的周向相位移动并不明显。
Aiming at investigation of engineering application,the counter rotating fan design technology for a civil high bypass ratio engine is researched including aerodynamic concept demonstration,aerodynamic design technology investigation,mechanical and flutter analysis,acoustic behavior analysis,off-design point matching and adjustment,and flow simulation of inlet distortion.Certain issues that might be encountered in future engineering application and their possible solutions are summarized.Compared with a conventional fan,the operation point of the rear stage for the counter rotating fan changes considerably.Therefore,too large a design incidence angle of the rear stage cannot be selected.Since flutter does not occur at the design point in this paper,it does not present a big issue,although the counter rotating fan rotors have a low vibration frequency due to their low rotational design speed.The counter rotating fan is effective in reducing noise emission because of its low rotational speed,and only 90 dB of far field sound pressure level is found in this paper.The counter rotating fan is found to perform well at off-design point.It seems unnecessary to open the stagger angle of the rear rotor for engineering application.Distortion passes through counter rotating fan blades with less damping,and the counter rotating makes the circumferential phase movement of the outlet distortion area unconspicuous.
出处
《航空学报》
EI
CAS
CSCD
北大核心
2014年第5期1226-1235,共10页
Acta Aeronautica et Astronautica Sinica
基金
航空科学基金(2008ZB06011)~~
关键词
对转风扇
气动设计
颤振
噪声
非设计点
匹配
畸变
counter rotating fan
aerodynamic design
flutter
noise
off-design point
matching
distortion
