Sakamoto Shuichi, Toda Kentaro, Seino Shotaro, Hoshiyama Kohta, Satoh Takamasa
Department of Engineering, Niigata University, Ikarashi 2-no-cho 8050, Nishi-ku, Niigata 950-2181, Japan.
Graduate School of Science and Technology, Niigata University, Ikarashi 2-no-cho 8050, Nishi-ku, Niigata 950-2181, Japan.
Materials (Basel). 2023 Aug 17;16(16):5671. doi: 10.3390/ma16165671.
In this study, the sound absorption coefficients of rice and buckwheat husks were estimated. Computed tomography (CT) images were processed to determine the circumference and surface area of voids in the granular material, and the normal incident sound absorption coefficients were derived. In addition, the tortuosity, which expresses the complexity of the sound wave propagation through the structure, was measured for each material. The theoretical sound absorption coefficients were then compared to the measured sound absorption coefficients with and without consideration of the tortuosity. A correction factor was used to bring the surface area of the granular material closer to the actual surface area and observed that the tortuosity obtained theoretical values that matched the trend of the measured values. These results indicate that using CT images to estimate the sound absorption coefficient is a viable approach.
在本研究中，对稻壳和荞麦壳的吸声系数进行了估算。对计算机断层扫描（CT）图像进行处理，以确定粒状材料中孔隙的周长和表面积，并得出垂直入射吸声系数。此外，还测量了每种材料的曲折度，该曲折度表示声波在结构中传播的复杂程度。然后，在考虑和不考虑曲折度的情况下，将理论吸声系数与测量的吸声系数进行比较。使用一个校正因子使粒状材料的表面积更接近实际表面积，并观察到考虑曲折度时得到的理论值与测量值的趋势相符。这些结果表明，利用CT图像估算吸声系数是一种可行的方法。
