Tracking background-oriented schlieren for observing shock oscillations of transonic flying objects

摘要

A detailed understanding of the in-flight behavior of high-speed flying objects is useful in the forensic investigation of crime scenes. In particular, for transonic flying objects with associated unsteady shock waves, long-duration and high-resolution measurements are desirable but difficult with conventional optical visualization methods. In this study, we propose a tracking background-oriented schlieren (BOS) method that uses a mirror-based high-speed optical axis controller and a striped retroreflective background. We combine prediction instruction including a compensator for the flight trajectory, high-speed visual feedback by silhouette recognition, and reference image generation from only a measurement image in the BOS visualization process. Experimentally, we successfully observe the shock oscillations of an actual high-speed flying object. (C) 2017 Optical Society of America