PDF(Pubmed)
Abstract：
Noise pollution is a major threat to the health and well-being of the entire world; this issue forces researchers to find new sound absorption and insulating material. In this paper, the sound absorption coefficient and vibration damping factor of panels manufactured from Cyperus pangorei rottb and ramie fiber reinforced with epoxy resin are explored. Cyperus pangorei rottb grass fiber and ramie fiber are widely available natural fibers. Cyperus pangorei rottb grass fiber is used in mat manufacturing, whereas ramie is widely used as a fabric. Using both of these fibers, six variant panels using a vacuum resin infusion process (VRIP) were fabricated. The panels were named C, R, CR, RCR-Flat, RCR-Curved, and RCR-Perforated. All the panels were tested for the sound absorption coefficient using an impedance tube with a frequency ranging up to 6300 Hz. Modal analysis was carried out by using the impulse hammer excitation method. A micro X-ray computed tomography (CT) scan was used to study the voids present in the panels. The results were compared among the six variants. The results show that the RCR-curved panel had the highest sound-absorbing coefficient of 0.976 at a frequency range between 4500 Hz to 5000 Hz. These panels also showed better natural frequency and damping factors. The presence of internal voids in these panels enhances sound absorption properties. These panels can be used at higher frequencies.
摘要：
噪声污染是对整个世界的健康和福祉的主要威胁;这个问题迫使研究人员寻找新的吸声和绝缘材料。在本文中,研究了以Cyperuspangoreirottb和环氧树脂增强的苎麻纤维制成的面板的吸声系数和振动阻尼系数。香附草根纤维和苎麻纤维是广泛可用的天然纤维。香附草根纤维用于垫子制造，而苎麻被广泛用作织物。使用这两种纤维，使用真空树脂灌注工艺（VRIP）制作了六个变体面板。面板被命名为C，R,CR,RCR-Flat,RCR曲线,和RCR穿孔。使用频率范围高达6300Hz的阻抗管测试所有面板的吸声系数。采用脉冲锤激励法进行模态分析。使用微X射线计算机断层扫描（CT）扫描来研究面板中存在的空隙。在六个变体之间比较结果。结果表明，RCR曲面面板在4500Hz至5000Hz的频率范围内具有最高的吸音系数，为0.976。这些面板还显示出更好的固有频率和阻尼因子。这些面板中内部空隙的存在增强了吸声性能。这些面板可以在更高的频率使用。
