With the rapid growth of population an‎d industrial development, noise pollution has become one of the major environmental an‎d social challenges faced by modern societies. According to reports by the World Health Organization, noise pollution can have severe adverse effects on human physical an‎d mental health. The use of porous sound-absorbing materials has been recognized as an effective strategy to mitigate noise pollution. Among these materials, spacer fabrics have significant potential for architectural acoustic applications due to their porous structure an‎d aesthetic properties. However, their limited thickness an‎d open structure reduce their sound absorption efficiency. This study aims to enhance the acoustic performance of these fibrous structures by producing three-dimensional prefabricated textiles based on spacer structures. The impact of various stitching parameters on the structure an‎d acoustic behavior of spacer fabrics was investigated. For sample preparation, different stitching patterns with stitch lengths of 3 an‎d 5 mm, machine speeds of 4 an‎d 20 rpm, stitch line spacings of 1.5 an‎d 2.5 cm, an‎d stitching directions (warp, weft, an‎d diagonal) were applied to spacer fabrics. Physical properties such as thickness, surface density, an‎d porosity of the samples were measured, an‎d their acoustic behavior was eva‎luated using the two-microphone impedance tube method based on the transfer function. The results revealed that increasing the thickness an‎d reducing the porosity of the structures improve sound absorption. Additionally, longer stitch lengths enhance sound absorption due to increased thickness. Reduced machine speed results in greater thickness an‎d lower porosity, leading to improved sound absorption over a broader frequency range. Furthermore, reducing the spacing between stitch lines increases the bulk an‎d surface density, resulting in a higher interaction between the fabric an‎d sound waves, thereby enhancing sound absorption. The findings of this study provide valuable insights for the design an‎d optimization of three-dimensional prefabricated textiles based on spacer structures for maximum sound absorption in various environments such as nurseries, music classrooms, gyms, an‎d residential complexes.

سعيد آجلي , پرهام سلطاني

ابراهيم تابان

حسين حسني , فاطمه حقيقت