Muhlestein Michael B, Ostashev Vladimir E, Wilson D Keith, Albert Donald G
U. S. Army Engineering and Research Development Center, 72 Lyme Road, Hanover, New Hampshire 03755-1290, USA.
J Acoust Soc Am. 2018 Feb;143(2):968. doi: 10.1121/1.5024352.
The propagation of acoustic pulses through a forest is considered. Multiple-scattering effects are accounted for by using the energy-based radiative transfer theory under a modified Born approximation, resulting in an expression for the diffuse intensity as a function of time and dominant frequency. While this expression is a complicated set of three integrals, certain practical approximations enable analytic evaluation of one, two, or even all three integrals. Any remaining integrals may be numerically calculated. The simple case of an impulse in an infinite homogeneous forest of diffuse scatterers is first considered, and then the effects of successively including non-diffuse scatterers, ground reflections in a forest of finite height, and finally a realistic forest model are analyzed with an emphasis on long-time decay and reverberation times. These theoretical findings are then compared with experimental results.
考虑了声脉冲在森林中的传播。在修正的玻恩近似下，通过基于能量的辐射传输理论来考虑多重散射效应，从而得到了作为时间和主频函数的漫射强度表达式。虽然这个表达式是一组复杂的三重积分，但某些实际近似使得可以对其中一个、两个甚至所有三个积分进行解析评估。任何剩余的积分都可以通过数值计算得到。首先考虑无限均匀漫射散射体森林中脉冲的简单情况，然后依次分析包括非漫射散射体、有限高度森林中的地面反射以及最终实际森林模型的影响，重点关注长时间衰减和混响时间。然后将这些理论结果与实验结果进行比较。
