ACTIVE 2009 Keynote

Professor Fuller has been invited to give a keynote address at the Australian Acoustical Society Annual Conference , Adelaide, Australia, 23 to 25 November, 2009. 

The title of his presentation is "Advanced Passive Treatment of Low Frequency Sound and Vibration"

 Abstract:

It is well known that standard poro-elastic materials and visco-elastic damping materials are ineffective at reducing low frequency sound and vibration. This paper overviews two new treatments developed at Virginia Tech which attempt to address this problem. HG material consists of poro-elastic material with embedded multiple small masses. The masses combine with the natural elasticity of the poro material matrix to create multiple vibration absorbers with a range of tune frequencies in the low frequency region. The embedded masses are found to significantly increase the low frequency transmission loss and absorption of the poro-elastic material. DVA’s are vibration absorbers whose active mass and spring are spread over a large area while still maintaining a viable damped reactive effect at low frequencies. DVA’s are found to provide global reduction of low frequency vibration of structures in a compact, lightweight configuration. DVA’s are also observed to provide mid to high frequency damping most likely to air squeeze damping effects. The paper will overview the concepts, development and testing of both devices. Applications of the new treatments to realistic structures will be considered.