Zhang, H., Zuo, P., Li, J., Zeng, Z., & Liu, Y. (2025). SAFE method for dispersion characteristics of fluid-saturated porous media with arbitrary cross sections. Ultrasonics, 155, 107745. https://doi.org/10.1016/j.ultras.2025.107745
Abstract:
Understanding the dispersion characteristics of guided waves is crucial for the application of ultrasonic guided wave method in fluid-saturated porous media. In this paper, the Semi-Analytical Finite Element (SAFE) method is applied to analyze the dispersion characteristics in fluid-saturated porous media. We derive the SAFE equations for fluid-saturated porous media and reformulate them into the standard Finite Element (FE) eigenvalue form that can be solved using COMSOL Multiphysics. Unlike the simple boundaries of elastic waveguides (such as free or rigid boundaries), the boundary conditions of fluid-saturated porous media present an additional challenge in the analysis of guided wave problems. We also derive the open-pore and closed-pore boundary conditions for fluid-saturated porous media and reformulate them into standard FE form. On this basis, we analyzed the causes of high-attenuation modes, wave structures, energy distribution, and the effects of surface treatment methods. The proposed method is first validated on waveguides with regular cross sections. Furthermore, we apply the SAFE method to L-shaped fluid-saturated porous bar for which there is no analytical solution, demonstrating the unique advantages of the SAFE method in solving the dispersion characteristics of irregular fluid-saturated porous media.
License type:
Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0)
Funding Info:
This work was supported in part by National Science Foundation of China under Contract No. 12474459, in part by the Natural Science Foundation of Zhejiang Province under Contract No. LY23E010001.