Abstract Hypersonic experiments are performed in the VKI Longshot wind tunnel on hemispherical and annular geometries representative of space debris, aiming at determining their lift, drag and pitching moment coefficients. A free-flight technique is used for this purpose where the model is automatically released in the hypersonic flow and safely recovered by the end of the experiment. A schlieren flow visualization technique coupled with a high-speed camera follows the motion of the object as it is exposed to the high-velocity flow. The instantaneous attitude of the free-flying model and its trajectory are determined from image analysis techniques. Correction terms are included to account for the gravity and for the relative motion of the object within the flow. Experimental results are compared with both numerics and theory. Graphic abstract

中文翻译：

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使用自由飞行测量技术对 VKI Longshot 高超声速隧道中的空间碎片进行空气动力学表征

摘要 在 VKI Longshot 风洞中对代表空间碎片的半球和环形几何结构进行了高超声速实验，旨在确定它们的升力、阻力和俯仰力矩系数。为此使用了一种自由飞行技术，其中模型在高超声速流中自动释放，并在实验结束时安全恢复。纹影流可视化技术与高速摄像机相结合，跟踪物体在高速流中的运动。自由飞行模型的瞬时姿态及其轨迹由图像分析技术确定。包括校正项以说明重力和流体中物体的相对运动。实验结果与数值和理论进行了比较。图形摘要