Abstract This work deals with an experimental investigation of the acoustic absorption of two kinds of materials, i.e. chips, and sawdust of red, and beechwood. For this purpose, several particle sizes classes, and thicknesses were tested in the impedance tube in the frequency range [50–1400] Hz. The results show that the classes of (0.31 mm−0.63 mm), (0.63 mm−1.25 mm), and (1.25 mm−2.5 mm) give a better absorption coefficient, while the classes equal or higher than (5 mm−8 mm) as well as the class (0.16 mm–0.315 mm) are the least efficient ones. Also, one of the best particle sizes, namely (1.25 mm-2.5 mm) from redwood was packaged in a piece of fabric and then used as an alternative absorbent panel to simulate the intelligibility parameters of a large conference room of 1220 m3 in the interval [50–6000] Hz. The influence of the fabric on the absorption coefficient was examined first, and then the measurements of the absorption coefficient have been extended up to 6000 Hz by calculation after estimating the all 8 non-acoustical parameters involved in the Johnson-Champoux-Allard-Pride-Lafarge (JCAPL) model. The comparison between the intelligibility parameters obtained with our panels, and those which we simulated using commercial perforated panels, shows that they are almost the same. Consequently, the proposed alternative solution allowed us to reduce the project’s budget compared to the situation where the classic perforated wood panels were utilized.

中文翻译：

---

松散木屑和锯末作为替代可持续吸声材料的研究

摘要 这项工作涉及两种材料的吸声实验研究，即木屑、红木屑和山毛榉木。为此，在阻抗管中在频率范围 [50–1400] Hz 内测试了几种粒径等级和厚度。结果表明，(0.31 mm-0.63 mm)、(0.63 mm-1.25 mm) 和 (1.25 mm-2.5 mm) 的等级给出了更好的吸收系数，而等于或高于 (5 mm-8 mm) 的等级) 以及类 (0.16 mm–0.315 mm) 是效率最低的。此外，最好的粒径之一，即来自红木的 (1.25 mm-2.5 mm) 被包装在一块织物中，然后用作替代吸水板来模拟 1220 m3 的大型会议室在间隔中的可懂度参数[50–6000] 赫兹。首先检查织物对吸收系数的影响，然后在估算了 Johnson-Champoux-Allard-Pride- 中涉及的所有 8 个非声学参数后，通过计算将吸收系数的测量扩展到 6000 Hz。拉法基 (JCAPL) 模型。用我们的面板获得的清晰度参数与我们使用商业穿孔面板模拟的参数之间的比较表明它们几乎相同。因此，与使用经典穿孔木板的情况相比，提议的替代解决方案使我们能够减少项目预算。然后在估算了 Johnson-Champoux-Allard-Pride-Lafarge (JCAPL) 模型中涉及的所有 8 个非声学参数后，通过计算将吸收系数的测量扩展到 6000 Hz。用我们的面板获得的清晰度参数与我们使用商业穿孔面板模拟的参数之间的比较表明它们几乎相同。因此，与使用经典穿孔木板的情况相比，提议的替代解决方案使我们能够减少项目预算。然后在估算了 Johnson-Champoux-Allard-Pride-Lafarge (JCAPL) 模型中涉及的所有 8 个非声学参数后，通过计算将吸收系数的测量扩展到 6000 Hz。用我们的面板获得的清晰度参数与我们使用商业穿孔面板模拟的参数之间的比较表明它们几乎相同。因此，与使用经典穿孔木板的情况相比，提议的替代解决方案使我们能够减少项目预算。