{"title":"Bubble shape instability of acoustic cavitation in molten metal used in ultrasonic casting","authors":"","doi":"10.1016/j.ultsonch.2024.107064","DOIUrl":null,"url":null,"abstract":"<div><p>In this study, we estimated the equilibrium bubble size of acoustic cavitation in a molten metal, which is basic information in ultrasonic casting. For this, the bubble shape instability of acoustic cavitation in the melt was numerically investigated by solving the Keller–Miksis equation and dynamic equation of the distortion amplitude. The acoustic cavitation bubbles are more stable in aluminum and magnesium melts than in water, and the <em>parametric instability</em> mainly determines the bubble stability at 20–160 kHz in molten metals. However, the <em>afterbounce instability</em> does not significantly affect the bubble stability in molten metals owing to the small number of bubble oscillations after the first rapid compression, and the distortion amplitude cannot grow significantly after the first compression. The bubbles in the melt become more unstable with an increase in the ultrasonic frequency owing to the corresponding increase in the bubble wall velocity. Through this stability analysis, we can estimate that the stable bubble size in the aluminum or magnesium melt is approximately three or four times larger than that in water at the same ultrasonic pressure amplitude.</p></div>","PeriodicalId":442,"journal":{"name":"Ultrasonics Sonochemistry","volume":null,"pages":null},"PeriodicalIF":8.7000,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S1350417724003122/pdfft?md5=62e4e88425966b2b76259c65bfffe671&pid=1-s2.0-S1350417724003122-main.pdf","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Ultrasonics Sonochemistry","FirstCategoryId":"92","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S1350417724003122","RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"ACOUSTICS","Score":null,"Total":0}
引用次数: 0
Abstract
In this study, we estimated the equilibrium bubble size of acoustic cavitation in a molten metal, which is basic information in ultrasonic casting. For this, the bubble shape instability of acoustic cavitation in the melt was numerically investigated by solving the Keller–Miksis equation and dynamic equation of the distortion amplitude. The acoustic cavitation bubbles are more stable in aluminum and magnesium melts than in water, and the parametric instability mainly determines the bubble stability at 20–160 kHz in molten metals. However, the afterbounce instability does not significantly affect the bubble stability in molten metals owing to the small number of bubble oscillations after the first rapid compression, and the distortion amplitude cannot grow significantly after the first compression. The bubbles in the melt become more unstable with an increase in the ultrasonic frequency owing to the corresponding increase in the bubble wall velocity. Through this stability analysis, we can estimate that the stable bubble size in the aluminum or magnesium melt is approximately three or four times larger than that in water at the same ultrasonic pressure amplitude.
期刊介绍:
Ultrasonics Sonochemistry stands as a premier international journal dedicated to the publication of high-quality research articles primarily focusing on chemical reactions and reactors induced by ultrasonic waves, known as sonochemistry. Beyond chemical reactions, the journal also welcomes contributions related to cavitation-induced events and processing, including sonoluminescence, and the transformation of materials on chemical, physical, and biological levels.
Since its inception in 1994, Ultrasonics Sonochemistry has consistently maintained a top ranking in the "Acoustics" category, reflecting its esteemed reputation in the field. The journal publishes exceptional papers covering various areas of ultrasonics and sonochemistry. Its contributions are highly regarded by both academia and industry stakeholders, demonstrating its relevance and impact in advancing research and innovation.