PhD Multi-scale modeling of acoustic materials

Within the research area Acoustics and noise control the project “Acoustic Shielding” will be started, funded by STW. The goal of this project is the design of advanced cover systems for acoustic shielding of high-tech systems. This project addresses the design of advanced cover systems to shield (parts of) high-tech systems such as MRI scanner, wafersteppers and electron microscopes. This project focuses on novel techniques for combined active-passive covers for high-tech applications, offering efficient acoustic shielding at mid and low frequencies. A breakthrough hybrid passive-active control approach is proposed for the advanced cover systems. For the mid frequency range (from 250 - 500 Hz) a passive approach for noise reduction based on multilayered porous covers will be combined with actively controlled actuators that counteract the noise in the low frequency range (below 250 Hz). Within the project two PhD’s and a postdoc will be working together on the development of passively and actively based acoustic shielding. For the passive shielding part, physical modelling techniques of multilayered foams and absorbing materials for high-tech environments taking into account the effects of their microstructure will be developed to enable the design of (passive) shielding systems that are efficient in the mid frequency range (250 - 500 Hz). The microstructure is taken into account by means of a multi-level prediction technique, bridging different length scales by means of physical modelling principles. Using the macro-scale models of the multilayered system, an optimization of the cover systems is aimed for.

The main scientific challenge lies in the extension of multi-scale modelling techniques already available at the Eindhoven University of Technology to acoustic applications, including dynamic effects. With these multi-scale modelling techniques, micromechanical based models should be translated to a macroscopic model which can be used for the optimization of the multilayered cover system. The tasks involve the characterisation of foams at micro-level, using advanced X-ray computer tomography, the modelling of foams at the micro-level (multi-scale) and a translation of the micro scale simulation results to a physical, parametric model. In cooperation with a post-doc, validation measurements will be carried out on a dedicated test-rig, followed by an optimization of the material properties for an improved acoustic performance. The research will be conducted in cooperation with the group of Dynamics & Control (TU/e) and a group of companies – producers of high-tech systems like wafer steppers and MRI-scanners.