Mechanical equipment with the stiffener has a strong interference with the propagation of acoustic emission (AE) signals from faults, reducing the accuracy of fault detection. This paper conducts an in-depth study of the interaction between AE signals and the stiffener. The installation constraints, that can separate the direct signal, signals scattered from the stiffener and signals reflected from the boundary in the time domain, for sensors are deduced based on the multipath propagation model of AE signals in the stiffened plate. On this basis, the scattering characteristics of AE signals with different frequencies in different height stiffened plates are predicted by simulations. Moreover, the reflection and transmission coefficients are calculated to quantify the scattering characteristics. The results show that the signal, undergoing a "T-shaped" transformation at the stiffener, generates various modes, among which the transmission signal accounted for the largest proportion. In addition, experiments are performed to verify the numerical simulations, and the results are in good agreement with the numerical simulations. This work clarifies the propagation characteristics of AE signals in stiffened plates, and the research can optimize the spatial arrangement for sensors.

中文翻译：

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基于多径传播模型的加筋板声发射信号传播特性研究

带有加强筋的机械设备对来自故障的声发射（AE）信号的传播有很强的干扰，降低了故障检测的准确性。本文对AE信号与加强筋之间的相互作用进行了深入研究。基于加筋板中声发射信号的多径传播模型，推导出传感器的安装约束，可以在时域中将直接信号、加筋散射信号和边界反射信号分离。在此基础上，通过仿真预测了不同频率的声发射信号在不同高度加筋板中的散射特性。此外，计算反射和透射系数以量化散射特性。结果表明，信号经过“