Ultrasonic Double-cavity Interaction And Movement Characteristics Of The Study

Unlike solids and gas inside the sound propagation, the sound intensity is large enough and there will be cavitation if the sound propagation in a liquid,which is the most characteristics of sound propagation in a liquid. Recently, the experimental study and the theoretical analysis of the cavitation phenomenon is the focus attention of people.Therefore,which lay a good foundation for the use of power ultrasound. Many factors affect the production of cavitation, and many complex nonlinear phenomena of the cavitation emerges,which is the reason for slow progress of cavitation. the test and application of the cavitation is the research focus. Such as,ultrasonic cleaning,ultrasonic environmental, medical ultrasound, sound chemical reactions, ultrasound treatment and ultrasound treatment, etc., which belong to the application of ultrasonic cavitation areas.In recent years,ultrasound dosage is concerned by people, which is the problem of the application of ultrasound and ultrasound medical treatment.So, we should make further study for the cavitation phenomenon from experiment and theory. Years ago,when researching papers,Taleyarkhan and others found the fusion effect in the United States OakRidge National Laboratory. a new way to produce fusion reactions emerge,and the reaction appears in the ultrasonic cavitation field. Perhaps a revolutionary of new nuclear reactor industry will outbreak during the researching in the future.Ultrasonic cavitation phenomenon from theory and numerical simulation are studied in this paper, we mainly do the following work:(1)The starting point of this paper is the theory of single cavitation bubble dynamics, and considering the incompressible and infinite liquid existing within the cavitation bubble (cavitation bubbles of gas is the ideal free gas),Cavitation bubble can appear two kinds of state with expand and compressed,because of some intervening factors.Then deduced the motion equation, vibration radius and natural resonant frequency equation of the single cavitation bubbles, and the motion of the mechanism and vibration of single cavitation bubble is explained respectively through matlab numerical calculation.(2)The motion equation of double cavitation is obtained, though the derivation of Rayleigh equation method.And compared theory of the dual cavitation bubble motion equation,obtained their similarities and differences. Meanwhile calculated the following conclusions by Matlab numerical calculation:When the initial radius and the incentive pressure is same, the effect of ultrasonic cavitation is stronger,if ultrasonic frequency is smaller;When the incentive pressure and ultrasonic frequency is same, the effect of ultrasonic cavitation is weaker,if the initial radius of cavitation bubbles is larger;When the initial radius of the cavitation bubble and the ultrasonic frequency is same, the effect of ultrasonic cavitation is weaker, if the ultrasonic irradiation pressure is smaller.However,as for two cavitation bubble,when other parameters are constant,cavitation bubble radius is decreased,and the breaking time extension.The reason of breaking process change slowly is cavitation bubble interactions.The interactions between two cavitation bubble can ignore,and equivalent to the motion situation of single cavitation bubble,when the distance between cavitation bubble approximating infinite (L(?)R1+R2)(3)According to the motion equation of the two cavitation bubble under the sound field,and obtained vibration displacement equation,the vibration velocity equation, cavitation bubble vibration equation, natural resonant frequency, vibration radius.When the parameter conditions remain unchanged,the vibration displacement, vibratory rate equation of the two cavitation bubble are calculated though Matlab numerical calculation language respectively.And concluded the following conclusions:when the distance between two cavitation bubble is certain, the displacement of the cavitation bubble is vibration until finally breaking complex in acoustic oscillations cycle,and the vibration amplitude is biger.The resonance frequency of the cavitation bubble increase with the distance between two cavitation bubble increased,and finally tend to a constant which is the resonance frequency of the single bubble.it still relate to the radius of the two cavitation bubble.Vibration amplitude of the cavitation bubble is related to initial radius of the two cavitation bubble,outside pressure,the distance of the two cavitation bubble.And it increase with the distance between two cavitation bubble,but finally tends to be a fixed value.