The Numerical Simulation Of Uca's Cavitation Bubble And The Experimental Research Of The Fluid Mixing

With the development of science and technology, ultrasound has been extensively applied in many fields. Ultrasonic cavitation is a unique physical phenomenon when ultrasonic acts on the liquid medium. It is the main power in practical application for ultrasonic. The growth and collapse of the cavitation bubble due to ultrasonic could arouse many physical and chemical effects such as accelerating the chemic reaction, destroying the biologic organization, generating the luminescence etc. The intensity of cavitation correlates with many factors, which makes many difficulties in the researches for the theory of cavitation. Therefore, the researches of the movement law of cavitation bubbles are very important in theory and experiment.In this paper, work has been done based on the theory and experiment researches of cavitation. The main work is as follows:(1) In the theory research, according to the movement law of cavitation, this paper regards a cavitation bubble as a bob, which is filled with liquid. This paper has detruded the cavitation bubble motion equation by the method of Rayleigh equation. And then the equation is solved by Matlab in different gas parameters of cavitation bubble. The result shows that: Van der Waals radius has a negligible effect on cavitation bubble motion. Under the same conditions, the gas of cavitation with the higher insulation factor could make the cavitation more power. To the UCA's gas selecting, the gas in the cavitation bubble with the lower insulation factor should be chosen. The initial radius of UCA's cavitation bubble should be chosen the size which is in the order of Micrometre ( 10?6 m).(2) In the experiment research, this paper has included two parts. One is to prove that the cavitation effect is the main power in the fluid mixing by analysing the image of the experiment. The other is to prove that the cavitation effect could make the fluid mixing homogeneous by analyzing the ph value. The result shows that: the microfluidics caused by the cavitation is the main power in the fluid mixing. The fluid mixing could be homogeneous under ultrasonic condition.