激光片光流动显示技术在高机动飞机布局设计中的应用

On the Application of Laser Sheet Flow Visualization in the Layout Design of a High Performance Aircraft

采用激光片光流动显示技术,针对某高机动布局飞机开展大迎角流动机理研究。结果表明激光片光流动显示技术具备捕捉复杂流动结构的能力,可以清晰观察双前翼布局大迎角下机头涡、第一前翼涡、第二前翼涡以及机翼涡等涡结构的生成、发展、融合等复杂流动结构的演化,并且揭示出涡结构扫略垂尾内侧使布局航向更加安定,偏转前翼将使旋涡绕流的涡心降低,造成布局升力提高,低头力矩增加。片光流动显示结果进一步表明,布局航向安定性不足,垂尾需要沿展向外移动,为布局深化设计提供了设计依据。

Flow mechanism of a high performance aircraft at high angle of attack was investigated by using laser sheet flow visualization. Results show that laser sheet flow visualization technology is able to capture complex flow structure, and also to observe clearly the generation, development and combination of the head vortex, the first forewing vortex, the second vortex and wing vortex, respectively. It also reveals the vortex flow around the inner vertical wing, which may improve the yaw stability of aircraft, and reveals forewing deflection which may result in vortex core lower than base instance, thus may increase lift and decrease pitch moment. Results of laser sheet flow visualization further show that the yaw stability of original layout design is insufficient, the vertical wing needs to be moved towards outside in span. Above results provide evidences for further design of the aircraft layout.