增强立尾效益的主动流动控制

Active flow control for enhancing vertical tail efficiency

本文叙述和讨论了某些增强立尾效益的主动流动控制(AFC)技术的研究。在NASA ERA项目支持下Rensselaer学院完成了4%和5%缩比立尾模型的合成射流AFC风洞试验,加州理工学院完成了14%缩比立尾模型的振荡射流AFC风洞试验,后者表明当动量系数为1.7%时可获50%的侧向力增量。基于将上述两种AFC技术集成于飞机系统的可行性研究,Boeing在Ames NFAC(40ft×80ft风洞)完成了B-757全尺寸立尾风洞模型试验,在风速为100knots,方向舵偏角为30°和侧滑角为0°与-7.5°下,得出采用31个振荡射流激振器可获得20%侧向力增量。NASA ERA项目组与Boeing共同努力在2015年春实现了装有31个振荡射流激振器的B-757ecoDemonstrator飞行试验。飞行员反馈和13%~16%侧向力增量的飞行试验初步分析结果表明了振荡射流AFC技术的成功。

Some research efforts of advancing Active Flow Control （AFC） technology to enhance the aerodynamic efficiency of a vertical tail is discussed in this paper. With the support of NASA ERA project, wind tunnel tests are performed on the synthetic jet AFC technology for 4 % and 5% subscale vertical tail models at the Rensselaer Polytechnic Institute, and wind tunnel tests are conducted on oscillating jet AFC technology for 14 % subscale vertical tail model at the California Institute of Technology. The latter experiment shows that 50 % side force enhancement is achieved when the momentum coefficient is 1. 7%. Based on research on feasibility of integrating the two AFC technologies for the aircraft system, Boeing completed a wind tunnel test （40ft×80ft） on a full-scale B-757 vertical tail model at NASA Ames NFAC, and found that 20% side force enhancement can be achieved using 31 oscillating jet actuator configuration at 100 knots, 30°rudder deflection, and the side slip angle ranging from 0°与-7.5°. Afterwards, flight test of B-757 ecoDemonstrator equipped with 31 oscillating jet actuators is performed in the spring of 2015 with the cooperation of NASA ERA project team and Boeing. Both the pilot feedback and the result of 13 %-16 % side force increment confirmed the success of the oscillating jet AFC.