Characterization of the noise emitted by a washing-machine due to the pump

Abstract

The noise sources during the pump operation of a washing machine are: the electric motor, the water–air impulsion, and the structural radiation of the pump-housing, hose, and cabinet. The determination of the sound power level under different working conditions let us identify that the noise emitted by the cabinet vibration was the more noticeable, being irrelevant the noise emitted by the other elements. In order to know which part of the cabinet is the noisiest, the standard ISO-TR 7849 was applied to calculate the contribution of the noise emitted by the structural radiation of each part of the cabinet to the total sound power level. This experimental procedure relates the noise radiated by a structure with its vibration velocity, and it was found that the kick plate was the more relevant element. Once the noise transmission paths have been characterized, the proposals to reduce noise are focused on a new design of the kick plate to make it more flexible and the modification of the join zone of the pump to the kick plate to reduce the force transmitted between both elements. (To be presented in Spanish.)