Study of Insulation with Complete Enclosure under Confined Space

• Main Authors: Yu-Hsing Cheng, 鄭宇星
• Other Authors: Hsueh-Wen Hsu
• Format: Others
• Language: zh-TW
• Published: 2006
• Online Access: http://ndltd.ncl.edu.tw/handle/91026007822022033554

碩士 === 國立聯合大學 === 環境與安全衛生工程學系碩士班 === 94 === In order to improve the situation of hearing loss of workers, this study used a complete insulation enclosure and inserted into several of absorbent materials, and to use the concept of the Insertion Loss (IL) and Transmission Loss (TL) to probing into the effects of noise reducing. To prevent this equipment from causing machinery and structures more weight, so this study choose widely used light materials to measure and analyzed absorbent effects of the various materials. It’s used the theorem of Insertion Loss (IL) and Transmission Loss (TL) to probing into the insulation effects of noise during experiment process. To use enclosure materials of unlike layers, and add some absorbent materials of mineral wools, sugarcane boards, and Styrofoam inserted. By the different partition of grille and porous board we can make an insulation device to measure the noise change with inside and outer of an insulation enclosure. From the experiment we expect to find fitting insulating materials. This study results showed： 1. In the closed space of the enclosure, it has significant correlation in materials between the transmission coefficient (τ) and noise absorbent coefficient (α). It was discovered that the τ was smaller comparison with the τ was higher meant if α≧τ, the insulation effectiveness will be better. 2. In use of the single enclosure material, the insertion loss value went with the thickness of enclosure. It was beneficial for sound insulation results by means of add the thickness of mineral wool inserted can reduce inside sound. 3. Use grille device can increase the fastness with insulation enclosure, and decrease coincidence effect with high frequency. To add the mineral wool inserted can also improve the part of low frequency. 4. By the way of porous board to cut down on noise energy along with increasing of porosity, it could increase the attrited loss with sound power and reduce noise volume effectively.