Overview
The primary goal of the project is to develop novel noise absorptive panels that can be applied for effective silencing of environmental and transportation noise.
This study aims to experimentally determine the MGPs acoustic properties, to develop mathematical/numerical models of the panel, to optimize the panel design and to verify the applicability of MGPs in automotive field.
Results
Micro grooved panels (MGPs) are innovative acoustic elements, whose silencing effect is based on the dissipation of the acoustic wave energy by the viscous friction imposed by passing the micro grooves. By following the novel meta-material principle a pattern of the micro grooves is machined onto one of the constituting panel layers and have sub millimeter cross sectional area. The acoustic damping effect is dependent on the configuration of the MGPs and the geometry of the micro grooves. By knowing the acoustic properties of the material it is possible to develop an effective sound absorber for certain application. The MGPs can be produced as cost effective, highly noise absorptive, light weight, noncombustible and environmentally friendly acoustic materials suitable for a wide variety of applications. The MGPs have been thought to overcome the cost issues of micro perforated panels (MPPs). The MPPs have sub millimeter perforations, where the noise dissipation effect is based on the viscous losses which reduce the energy of sound waves propagating through the perforated apertures. A great advantage of this type of acoustic material is regarded to be an effective noise absorption without using fibrous materials. On the other hand, the requirement for several sub-millimeter holes with certain accurate geometry per each square cm of the panel, causes high technological (i.e. laser beam penetration) and manufacturing procedures to be expensive and time consuming. The MGPs are intended to be less expensive alternative for MPPs while offering comparable acoustic performance.