3-D laser vibration measurement and an analysis of the unsteady flow-field and aerodynamic sound of turbo fan motor in a vacuum cleaner

The vacuum cleaner motor runs at very high speed for suction power. Specially, motor power is provided by the impeller being rotated at very high speed. The centrifugal fan consists of the impeller, the diffuser and the circular casing. Due to the high rotating speed of the impeller and small a gap distance between the impeller and diffuser, the level of noise in the centrifugal fan is at BPF and harmonic frequencies. In order to calculate the sound pressure of centrifugal fan, unsteady flow data are needed. Noise cause is obtained by dividing the fluid noise by exhaust flow of fan and vibration noise by rotational vibration of vacuum cleaner fan motor. Until now, an accelerometer has been used to measure vibration. However, this machine does not measure vibration in some parts of brush and commutator because of motor construction and 3-D vibrating mode. This study was conducted to perform accurate analysis using a laser vibration analyzer. A silent fan motor can be designed using the data measured in this study.