Search Results

Regulations stipulating the design of motorcycle silencers are strict, especially when the unit incorporates fibrous absorbing materials. Therefore, innovative designs substituting such materials while still preserving acceptable level of characteristic sound are currently of interest. Micro perforated elements are innovative acoustic solutions, which silencing effect is based on the dissipation of the acoustic wave energy in a pattern of sub-millimeter apertures. Similarly to fibrous materials the micro-perforated materials have been proved to provide effective sound absorption in a wide frequency range. Additionally, the silencer is designed as a two-stage system that provides an optimal solution for a variety of exploitation conditions. In this paper a novel design for a cruiser type motorcycle silencer, based on micro-perforated elements, is presented.

In this paper the acoustic performance of silencers has been investigated. The experimental techniques to study the attenuation of a silencer are in focus. A novel test procedure has been described and used to determine the sound transmission through the silencers in hot mean flow conditions. The experiments have been carried out on two motorcycle engine silencers with different design. The results analyzed and discussed clearly present the influence of the induct flow conditions on the sound transmission loss of the silencer.