Study on Transonic Transverse Instability Flow Mechanism of Small Aspect Ratio Flying Wings Based on PSP/PIV Technology
The aircraft with low aspect ratio flying wing layout adopts the shape of large swept delta wing,which is prone to transverse instability movement in transonic state.In order to study its occurrence mechanism and development process,this paper comprehensively adopts PSP/PIV flow field visualization techniques and combines with free-to-roll test to obtain the change process of model surface and space wake.The asymmetrical phenomena of the left and right wing surface flow field and space wake are captured successfully under the condition of transverse instability of the wing model with low aspect ratio.The results show that there is no obvious asymmetry in the pressure distribution of the model surface and the space wake at a low angle of attack.When the angle of attack increases,the attached vortices on the model surface break up and asymmetrically separate,resulting in high frequency and unequal amplitude oscillations of the pressure on the left and right wings,and leading to the occurrence of wing rock motion.
PSPPIVsmall aspect ratio flying winglateral departure motionfree to roll
NETL
NSTL
万方数据
