Structure-borne Noise Reduction in Washing Machines: Noise Reduction by Modal Analysis

Ricky Kim , Rob Lawrence

New Zealand Acoustics, 18(4), pp.18- 21 . (2005).

There was an unlucky coincidence between a washing machine motor generating frequency and the resonant frequency of a certain motor part. For investigation and refinement work, modal analysis was done using both FEA and experimentation. A simplified model was used to save time during the FEA modal analysis. Shifting the resonant frequency and adding isolation provided a noise reduction of 3 dBA in one particular washing cycle.