Mao Qibo, Zhong Haibing
School of Mechanical Engineering, Yangzhou University, Yangzhou 225127, China.
School of Aircraft Engineering, Nanchang Hang Kong University, Nanchang 330063, China.
Sensors (Basel). 2017 May 16;17(5):1111. doi: 10.3390/s17051111.
The theory for calculation and/or measurement of sound power based on the classical velocity-based radiation mode (V-mode) approach is well established for planar structures. However, the current V-mode theory is limited in scope in that it can only be applied to conventional motion sensors (i.e., accelerometers). In this study, in order to estimate the sound power of vibrating beam and plate structure by using polyvinylidene fluoride (PVDF) films as sensors, a PVDF-based radiation mode (C-mode) approach concept is introduced to determine the sound power radiation from the output signals of PVDF films of the vibrating structure. The proposed method is a hybrid of vibration measurement and numerical calculation of C-modes. The proposed C-mode approach has the following advantages: (1) compared to conventional motion sensors, the PVDF films are lightweight, flexible, and low-cost; (2) there is no need for special measuring environments, since the proposed method does not require the measurement of sound fields; (3) In low frequency range (typically with dimensionless frequency < 4), the radiation efficiencies of the C-modes fall off very rapidly with increasing mode order, furthermore, the shapes of the C-modes remain almost unchanged, which means that the computation load can be significantly reduced due to the fact only the first few dominant C-modes are involved in the low frequency range. Numerical simulations and experimental investigations were carried out to verify the accuracy and efficiency of the proposed method.
基于经典的基于速度的辐射模式（V 模式）方法来计算和/或测量声功率的理论，对于平面结构已经非常成熟。然而，当前的 V 模式理论在范围上存在限制，因为它仅能应用于传统的运动传感器（即加速度计）。在本研究中，为了使用聚偏二氟乙烯（PVDF）薄膜作为传感器来估计振动梁和板结构的声功率，引入了一种基于 PVDF 的辐射模式（C 模式）方法的概念，以从振动结构的 PVDF 薄膜的输出信号确定声功率辐射。所提出的方法是 C 模式振动测量和数值计算的混合方法。所提出的 C 模式方法具有以下优点：（1）与传统运动传感器相比，PVDF 薄膜重量轻、柔韧性好且成本低；（2）不需要特殊的测量环境，因为所提出的方法不需要测量声场；（3）在低频范围内（通常无量纲频率<4），C 模式的辐射效率随着模式阶数的增加而迅速下降，此外，C 模式的形状几乎保持不变，这意味着由于在低频范围内仅涉及前几个主导 C 模式，计算负荷可以显著降低。进行了数值模拟和实验研究以验证所提出方法的准确性和效率。
