摘要
后退波是声波导中群速度与相速度方向相反的波,在控制声能流方面有诸多潜在的应用。本文利用动态光弹法观测了板中的后退波,一方面给出了后退波的直观物理图像,另一方面测量了后退波的群速度,验证了理论预测,相关结果可为研究后退波的物理机理以及工程应用提供参考。
The group velocity of backward wave is in the opposite direction to its phase velocity in wave guide, which finds many potential applications in the control of wave energy transportation. In this paper, backward waves are visualized by dynamic photoelastic technique. The intuitional physical images of backward waves are illustrated and the group velocities are measured to verify the theoretical predictions. The research on physical mechanics and engineering applications of backward waves can benefit from this work.
引文
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