Self-nucleated nuclear effect of acoustic cavitation in focusing acoustic field

Qian Cheng; Xin-Nian Li; Meng-Lu Qian; Yin-Guan Wang

doi:10.1121/1.4708036

Effect of Hydrophone Tip Shape on Acoustic Field and Acoustic Cavitation Behavior

2020 IEEE International Ultrasonics Symposium (IUS) ◽

10.1109/ius46767.2020.9251285 ◽

2020 ◽

Author(s):

Nagaya Okada ◽

Michihisa Shiiba ◽

Fujimaru Kaise ◽

Shinobu Yamauchi ◽

Toshio Sato ◽

...

Keyword(s):

Acoustic Field ◽

Acoustic Cavitation ◽

Cavitation Behavior

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Development of anticavitation hydrophone using a titanium front plate: Effect of the titanium front plate in high-intensity acoustic field with generation of acoustic cavitation

Japanese Journal of Applied Physics ◽

10.7567/jjap.55.07ke16 ◽

2016 ◽

Vol 55 (7S1) ◽

pp. 07KE16 ◽

Cited By ~ 8

Author(s):

Michihisa Shiiba ◽

Nagaya Okada ◽

Minoru Kurosawa ◽

Shinichi Takeuchi

Keyword(s):

Acoustic Field ◽

High Intensity ◽

Acoustic Cavitation ◽

Front Plate

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Numerical and Experimental Studies on the Effect of Surface Roughness and Ultrasonic Frequency on Bubble Dynamics in Acoustic Cavitation

Energies ◽

10.3390/en13051126 ◽

2020 ◽

Vol 13 (5) ◽

pp. 1126

Author(s):

Rana Altay ◽

Abdolali K. Sadaghiani ◽

M. Ilker Sevgen ◽

Alper Şişman ◽

Ali Koşar

Keyword(s):

Surface Roughness ◽

Chemical Reactions ◽

Acoustic Field ◽

Bubble Size ◽

Bubble Dynamics ◽

Video Recording ◽

Acoustic Cavitation ◽

Working Fluid ◽

Ultrasonic Frequency ◽

Effect Of Surface

With many emerging applications such as chemical reactions and ultrasound therapy, acoustic cavitation plays a vital role in having improved energy efficiency. For example, acoustic cavitation results in substantial enhancement in the rates of various chemical reactions. In this regard, an applied acoustic field within a medium generates acoustic streaming, where cavitation bubbles appear due to preexisting dissolved gas in the working fluid. Upon cavitation inception, bubbles can undergo subsequent growth and collapse. During the last decade, the studies on the effects of different parameters on acoustic cavitation such as applied ultrasound frequency and power have been conducted. The bubble growth and collapse mechanisms and their distribution within the medium have been classified. Yet, more research is necessary to understand the complex mechanism of multi-bubble behavior under an applied acoustic field. Various parameters affecting acoustic cavitation such as surface roughness of the acoustic generator should be investigated in more detail in this regard. In this study, single bubble lifetime, bubble size and multi-bubble dynamics were investigated by changing the applied ultrasonic field. The effect of surface roughness on bubble dynamics was presented. In the analysis, images from a high-speed camera and fast video recording techniques were used. Numerical simulations were also done to investigate the effect of acoustic field frequency on bubble dynamics. Bubble cluster behavior and required minimum bubble size to be affected by the acoustic field were obtained. Numerical results suggested that bubbles with sizes of 50 µm or more could be aligned according to the radiation potential map, whereas bubbles with sizes smaller than 10 µm were not affected by the acoustic field. Furthermore, it was empirically proven that surface roughness has a significant effect on acoustic cavitation phenomena.

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Augmentation of Vortex Cavitator Performance by the Use of Co-Directional Swirl of the Flux after Vortex Chamber

Progress in Agricultural Engineering Sciences ◽

10.1556/446.15.2019.1.1 ◽

2019 ◽

Vol 15 (1) ◽

pp. 1-22

Author(s):

Evgeniy Gennadievich Ivanov ◽

Boris Ivanovich Gorbunov ◽

Alexander Valentinovich Pasin ◽

Boris Alexandrovich Aryutov ◽

Alexei Ivanovich Novozhilov

Keyword(s):

Acoustic Field ◽

Experimental Studies ◽

Acoustic Cavitation ◽

Vortex Chamber ◽

Input Power ◽

The Body ◽

Original Design ◽

Pump Impeller ◽

Rotating Body ◽

Pump Inlet

Abstract Background: Acoustic cavitation is the creation and collapse of cavitation caverns in liquid in an acoustic field with a frequency of f = 1–3 kHz. The acoustic-cavitation processes manifest themselves during the collapse phase, with high pressure gradient continuum deformation, with a multiple transformation of energy forms. Liquid whistles are widely used to create an acoustic field of high power, but their efficiency only reaches 6–12%. We propose a liquid whistle in the form of a vortex cavitator (analogue of the Ranque vortex tube) with a rotating body in which a reduction in the input power is predicted. Objective: Verification of feasibility of using a rotating body in a vortex cavitator with a rotation co-directional to the operational pump impeller. Method: The method for identifying the feasibility of using a rotating body is to exclude body from the prototype and directly connect vortex chamber outlet with the pump inlet, which ensures the most complete preservation of co-directional vortex component of the flux entering the pump impeller. Results: The results of experimental studies confirmed the validity of the hypothesis to a greater extent, since we achieved an increase in pressure at the outlet of the pump and a decrease in power at the drive relative to the original design. Conclusions: The feasibility of designing the vortex cavitator body with rotation capability has been established, which will provide a reduction in input power of at least 30% by a rotation of the body, co-directional with the impeller.

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