Çok Katmanlı Yapılarda Ses Dalgası Yayılımının İncelenmesi

Abstract

Acoustic insulation due to industrial and environmental noise has become very important nowadays. These types of acoustic insulation materials and acoustic damping systems are frequently used in sectors such as housing, automotive, and white goods, as well as in the defense industry where acoustic secrecy is also important. Multi-layer structures with solid, liquid and porous properties are used for insulation in various engineering applications. The problem of sound transmission over the veneered panel structure has been extensively investigated in the literature, but the study of sound propagation in multilayered structures, which are layered in a special sequence, is a new research topic. In this thesis, multi-layered structures, which are layered in a special sequence, were modeled considering boundary conditions and surface characteristics using Transfer Matrix Method (TMM). In that way, sound structure interaction and acoustical performance was analyzed. The acoustic insulation performance was comprised between two-layer structures and the multi-layered structures, which are made of same materials and same total layer thickness to analyze effects of layer numbers on acoustic performance. In order to examine the effect of special sequence layered structures on acoustic performance, multi-layer structures wereiv arranged according to the different generations of the Fibonacci Sequence and compared with the two-layer structures, which are formed with the same material and the same total layer thickness. Finally, the sound structure interactions of the multilayer structures, which are ordered by different generations of the Fibonacci Series with same material, same total layer thickness and same number of layers, were compared among themselves to analyze which Fibonacci Sequence generation has best acoustic insulation performance.