3D-PTV study of flow inside the vacuum cleaner head

While vacuum cleaners with a motorized brush inside cleaner head are widely used, the influence of the brushes on dust collection performance has not been clarified. For this purpose, it is necessary to examine a flow inside a cleaner head. In this study, we measured the velocity distribution inside the commercial cleaner head with the rotating brush. The mean velocity field inside the head was captured by 3D-PTV. In the absence of the brush, the existence of reverse flow away from the suction port was observed. The flow heading to the suction port along the inner wall surface could be confirmed. With the stationary brush, the reverse flow was suppressed. While the fast flow near the floor surface was passing through the bristles of the brush, the fluids distant from the floor moved along them. Also the formation of the vortices between the bristles was observed. With the rotating brush, the deceleration due to collision with bristles was slightly reduced, so the flow was heading to suction port without forming the vortices. Also the flow along the inner wall surface was similar to the case without the brush.