摘要
采用延迟脱体涡模拟方法计算共形光学窗口转塔和平面光学窗口转塔的绕流流场,并根据绕流流场定量分析在转角0°、90°和180°下两种光学窗口的气动光学效应和远场衍射结果。采用Zernike多项式拟合波前,并结合自适应光学分析两种光学窗口所发射光线的传输性能。结果表明:在无自适应光学矫正下,平面光学窗口在0°和180°转角下的光线传输性能优于共形光学窗口,90°则相反;在自适应光学矫正平移、倾斜、离焦和像散等低阶项时,共形光学窗口在90°和180°转角下其光线传输性能都优于平面光学窗口;而在0°转角下,两种光学窗口的光线传输性能相近。随着转角的增大,两种光学窗口气动光学效应中的高阶项不断减小。值得注意的是,近场畸变的光线在远场衍射后的光强峰值可能会大于未畸变光线远场衍射的光强,且其光强峰值位置会严重偏移。
Delayed detached eddy simulation(DDES)is used to simulate the flow field around the conformal optical window turret and the flat optical window turret.The aero-optical effect and the far-field diffraction result of the two optical windows at 0°,90°and 180°angles are quantitatively analyzed based on the flow field around the turret.Zernike polynomial is applied to fit the wavefront distortion,and the adaptive optics is used to analyze the propagation performance of the two optical windows.The results show that the beam transmission performance of the flat optical window is better than that of the conformal one at the angles of 0°and 180°without adaptive optical correction,while the beam transmission performance of the conformal window at 90°angle is better than that of the flat one.When the adaptive optics correct these low-order terms including piston,tilt,defocus and astigmatism,the beam transmission performance of the conformal optical window is better than that of the flat one at the angles of 90°and 180°.At the angle of 0°,the beam transmission performance of the two optical windows is similar.With the increase of the angle,the high-order terms of the two windows decrease continuously.It is worth noting that the peak intensity of the distorted beam after diffraction in the far field may be larger than that of the undistorted beam in the far field.Meanwhile,the location of the peak intensity will be seriously offset.
作者
谭小童
许和勇
田仁治
TAN Xiaotong;XU Heyong;TIAN Renzhi(National Key Laboratory of Aerodynamics of Airfoil and Cascade,Northwestern Polytechnical University,Xi’an 710072,China;School of Aerospace Engineering,Technische Universiteit Delft,Delft 999025,Netherlands)
出处
《空气动力学学报》
CSCD
北大核心
2023年第6期71-80,I0002,共11页
Acta Aerodynamica Sinica
基金
翼型、叶栅空气动力学国家级重点实验室基金。
