In this paper, we propose a novel porous metamaterial structure with an improved acoustic energy absorption performance at high-temperature and in the low-frequency range. In the proposed novel porous metamaterial structure, a porous material matrix containing periodically perforated cylindrical holes arranged in a triangular lattice pattern is applied, and additional interlayers of another porous material are introduced around these perforations. The theoretical model is established by adopting the double porosity theory for the interlayer and the cylindrical hole which form an equivalent inclusion and then applying the homogenization method to the porous metamaterial structure formed by the equivalent inclusion and the porous matrix. The temperature-dependent air and material parameters are considered in the extended theoretical model, which is validated by the finite element results obtained by COMSOL Multiphysics. The acoustic or sound energy absorption performance can be improved remarkably at very low frequencies and high temperature. Furthermore, the underlying acoustic energy absorption mechanism inside the unit-cell is investigated by analyzing the distribution of the time-averaged acoustic power dissipation density and the energy dissipation ratio of each constituent porous material. The results reveal that regardless of the temperature, the acoustic energy is mostly dissipated in the porous material with a lower airflow resistivity, while the acoustic energy dissipated in the porous material with a higher airflow resistivity also becomes considerable in the high-frequency range. The novel porous metamaterial structure proposed in this paper can be efficiently utilized to improve the acoustic energy absorption performance at high temperature.

在本文中，我们提出了一种新型多孔超材料结构，在高温和低频范围内具有改进的声能吸收性能。在所提出的新型多孔超材料结构中，应用了一种多孔材料基质，该基质包含以三角形格子图案排列的周期性穿孔圆柱孔，并在这些穿孔周围引入另一种多孔材料的附加夹层。该理论模型是对形成等效夹杂物的夹层和圆柱孔采用双孔隙率理论，然后对等效夹杂物与多孔基体形成的多孔超材料结构应用均质化方法建立的。在扩展的理论模型中考虑了与温度相关的空气和材料参数，COMSOL Multiphysics 获得的有限元结果对此进行了验证。在极低频率和高温下，声学或声能吸收性能可显着提高。此外，通过分析各构成多孔材料的时均声功率耗散密度和能量耗散比的分布，研究了晶胞内部的潜在声能吸收机制。结果表明，无论温度如何，声能主要在气流电阻率较低的多孔材料中耗散，而在气流电阻率较高的多孔材料中耗散的声能在高频范围内也变得相当可观。