Pan Siwei, Jiang Weikang, Zhang Haibin, Xiang Shang
State Key Laboratory of Mechanical System and Vibration, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China.
J Acoust Soc Am. 2014 Oct;136(4):1744-55. doi: 10.1121/1.4895705.
A half-space interpolated time-domain equivalent source method (ITDESM) is proposed to model the transient sound propagation over an absorbing plane. In this approach, a closed-form transient half-space Green's function (i.e., the impulse response function in three-dimensional space) for a pure absorbing infinite plane is introduced to develop the half-space ITDESM formulation. Instead of the free transient Green's function employed in the conventional ITDESM, such Green's function contains the reflection effect of the absorbing plane. As a numerical example, reconstructing the transient pressure fields from two monopole sources is depicted, where both monopoles are located in front of an infinite plane with absorbing impedance. Simulation results indicate that the half-space ITDESM can reconstruct the half-space transient sound fields in both the space and time domains very well. The proposed method is also investigated by taking into account the measurement noise in the reconstruction process. An experiment of an impacted steel plate above a glass wool board is presented to illustrate the validity of the proposed method under actual conditions.
提出了一种半空间插值时域等效源方法（ITDESM）来模拟瞬态声音在吸收平面上的传播。在这种方法中，引入了纯吸收无限平面的闭式瞬态半空间格林函数（即三维空间中的脉冲响应函数）来推导半空间ITDESM公式。与传统ITDESM中使用的自由瞬态格林函数不同，这种格林函数包含了吸收平面的反射效应。作为一个数值例子，描述了从两个单极子源重建瞬态压力场的过程，其中两个单极子都位于具有吸收阻抗的无限平面之前。仿真结果表明，半空间ITDESM能够在空间和时域中很好地重建半空间瞬态声场。还通过考虑重建过程中的测量噪声对所提出的方法进行了研究。给出了在玻璃棉板上方冲击钢板的实验，以说明所提出方法在实际条件下的有效性。
