Abstract
In order to get improved bubbly water containing greater number of bubbles with smaller diameters than conventional ones, a new microbubble generation device has been developed, where a rotating porous plate is applied to the air intake unit of the device and compressed air is taken into the device through the rotating porous plate. The theoretical analysis shows that the bubble diameter detaching from the rotating porous plate decreases with the increase of the rotational speed, which results in the increase of air dissolution into working water in the mixing box. The experimental results obtained by the new device with a rotating porous plate show that the smallest mean diameter of bubbles is 11μm, the highest number density is 6.5×102/mm3 and the bubble generation rate reaches 1.5×107 number/s. It is also proved that the mean diameter is smaller and the number density is higher than those of bubbly waters generated by conventional devices, and that the bubble diameter and the number density could be effectively controlled by the rotational speed of the porous plate.
