ASA 129th Meeting - Washington, DC - 1995 May 30 .. Jun 06

2pED3. A dynamic absorber and a side-branch resonator for vibration and noise control.

M. G. Prasad

E. Zanone

S. Abbattista

Noise and Vibr. Control Lab., Dept. of Mech. Eng., Stevens Inst. of Technol., Castle Point on the Hudson, Hoboken, NJ 07030

This paper presents two demonstrations. The first one deals with control of vibrations of a motor under unbalance excitation. A dynamic absorber is used to reduce vibrations of the motor. The resonance phenomenon and mode shapes in vibrating systems will be shown. The second system is a finite length duct with an acoustic source (speaker) at one end. A Helmholtz resonator as a side-branch device is used to reduce the noise radiating from the open-end of the duct. Audible effects due to acoustic resonances in the duct and side-branch resonator system will be presented.