The educational value of time–domain animations for visualizing acoustic impulse scattering from spheres, and the formation of scattered wave fronts, is demonstrated. Anderson's fluid sphere theory [J. Acoust. Soc. Am. 22, 426–431 (1950)] is used to demonstrate scattering for two cases: (a) a fixed rigid sphere; (b) a pressure release sphere. The backscattering regime is seen to be dominated by geometric reflections. In the forward scatter region, visualizations for both cases show that the incident and forward scattered fields combine to rapidly minimize amplitude and phase perturbations of the wave front, leading to "wave front healing." Diffraction into the acoustic shadow behind the sphere is seen and, in the rigid case, leads to a clearly discernible circumferential wave that breaks off in the backward direction. Animations based upon the raypath scatter method depict how this technique represents geometrical reflections, while omitting diffraction effects, but appears to be a reasonable approximation for backscattering applications. The Hickling and Wang "movable" rigid sphere theory [J. Acoust. Soc. Am. 39, 276–279 (1966)] is used to create an animation that illustrates the "rebound" response motion of a sphere of finite mass to the action of the incident field. The animations discussed are downloadable via the World Wide Web.
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机译：演示了时域动画对球体声脉冲散射以及散射波阵面形成的可视化教育价值。安德森流体球理论[J． co Soc。上午。 22，426–431（1950）]用于说明两种情况下的散射：（a）固定的刚性球体; （b）泄压球。可以看出，后向散射机制主要是几何反射。在前向散射区域中，两种情况的可视化结果都表明，入射场和前向散射场相结合，可以快速最小化波前的振幅和相位扰动，从而实现“波前愈合”。可以看到在球体后方的声影中发生的衍射，在刚性情况下，会导致清晰可辨的圆周波，该圆周波在向后的方向上破裂。基于射线路径散射法的动画描绘了该技术如何表示几何反射，同时省略了衍射效应，但对于反向散射应用而言似乎是一个合理的近似值。 Hickling和Wang的“活动”刚性球理论[J. co Soc。上午。 39，276–279（1966）]用于创建动画，该动画说明了有限质量的球体对入射场作用的“回弹”响应运动。讨论的动画可通过万维网下载。
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