Institute of Sound and Vibration Research, Hefei University of Technology, Hefei 230009, People's Republic of China.
J Acoust Soc Am. 2011 Sep;130(3):1430-40. doi: 10.1121/1.3621005.
Transient nearfield acoustic holography based on an interpolated time-domain equivalent source method (ESM) is proposed to reconstruct transient acoustic fields directly in the time domain. Since the equivalent source strengths solved by the traditional time-domain ESM formulation cannot be used to reconstruct the pressure on the source surface directly, an interpolation function is introduced to develop an interpolated time-domain ESM formulation which permits one to deduce an iterative reconstruction process. As the reconstruction process is ill-conditioned and especially there exists a cumulative effect of errors, the Tikhonov regularization is used to stabilize the process. Numerical examples of reconstructing transient acoustic fields from a baffled planar piston, an impulsively accelerating sphere and a cube box, respectively, demonstrate that the proposed method not only can effectively reconstruct transient acoustic fields in the time domain, but also can visualize acoustic fields in the space domain. And, in the first numerical example, the cumulative effect of errors and the validity of using the Tikhonov regularization to suppress the errors are described.
基于插值时域等效源法（ESM）的瞬态近场声全息技术被提出，用于直接在时域中重建瞬态声场。由于传统时域 ESM 公式求解的等效源强度不能直接用于重建源表面上的压力，因此引入了插值函数来开发允许推导出迭代重建过程的插值时域 ESM 公式。由于重建过程是病态的，特别是存在误差的累积效应，因此使用 Tikhonov 正则化来稳定该过程。分别对带障平面活塞、脉冲加速球体和立方箱体瞬态声场的重建数值示例表明，所提出的方法不仅可以有效地在时域中重建瞬态声场，还可以可视化空间域中的声场。并且，在第一个数值示例中，描述了误差的累积效应以及使用 Tikhonov 正则化抑制误差的有效性。
