In this paper, we numerically study interactions of a short-pulsed plane acoustic wave with complex rigid objects by solving the linearized Euler equations. For the study, our numerical approach implements an immersed boundary method to satisfy the no-penetration condition on the surface of rigid objects, together with a fully-explicit staggered-grid finite-difference time-domain method having perfectly matched layers. First, we validate our approach for acoustic wave scattering by a circular cylinder, a well-known benchmark problem. Subsequently, we extend our simulations to two representative problems, namely interactions with a circular cylinder and a plano-concave lens which are of paramount interest in terms of acoustic force and acoustic focusing, respectively. Our simulations allow us to better understand the main mechanism of propagation, reflection, and scattering of acoustic waves as a result of interaction with rigid objects. In addition, the effects of pulse width on the interactions are closely investigated.

在本文中，我们通过求解线性化欧拉方程来数值研究短脉冲平面声波与复杂刚性物体的相互作用。在研究中，我们的数值方法实现了浸入边界方法，以满足刚性物体表面的无渗透条件，以及具有完美匹配层的完全显式交错网格有限差分时域方法。首先，我们验证了我们通过圆柱体进行声波散射的方法，这是一个众所周知的基准问题。随后，我们将模拟扩展到两个有代表性的问题，即与圆柱和平凹透镜的相互作用，这两个问题分别在声力和声聚焦方面最受关注。我们的模拟使我们能够更好地了解传播的主要机制，由于与刚性物体相互作用而导致声波的反射和散射。此外，仔细研究了脉冲宽度对相互作用的影响。