Abstract
The characteristic of generating the micro bubble by the strong swirl jet from the orifice nozzle is studied experimentally and theoretically. For the evaluation of the aspect of micro bubble generation, a method using the transmittance of the light is used in the water tank with a circulation system. By the method the parameters of the average diameter of micro bubbles, the bubble generation rate and the number density are obtained, and the characteristic of the micro bubble generator can be easily evaluated. The mechanism of the micro bubble generation is examined on the basis of the momentary photography and numerical simulation, and it is shown that the miniaturization of the bubble is caused by the division of a cylindrical large bubble in the two opposed flow in the orifice exit.
