{"title":"气泡坍塌特性的壁距影响实验","authors":"","doi":"10.1016/j.apor.2024.104277","DOIUrl":null,"url":null,"abstract":"<div><div>At present, the energy released by bubble collapse can be used for the surface treatment of workpieces and can also be used to degrade pollutants. However, the mechanism of action between bubble collapse and a nearby wall has yet to be accurately explained. In order to grasp the relationship between the wall distance and collapse characteristics, the methods of spark discharge, high-speed photography, and pressure acquisition are used to study bubble shapes and the dynamic variation during pressure release with different wall distances in this paper. The results show that with the increasing of the distance <em>L</em>, the shape of a bubble changes from oblate to spherical and its collapse time shortens. The proportion of the total collapse time consumed by the slow collapse stage shows an increasing trend. In an experiment with two contractions, the time proportion of the slow collapse stage of the first contraction is much larger than that of the second contraction. The existence of the wall delays the collapse of the bubble. As the distance <em>L</em> increases, the bubble goes from undergoing one collapse to two collapses and then to one collapse again. The proportion of the duration of the slow collapse stage of the first contraction decreases rapidly, and the proportion of the slow collapse stage of the second contraction increases slowly, but the time proportion of second contraction decreases. When the distance <em>L</em> increases from 4.5 mm to 11 mm, the pressure received by the wall gradually decreases 28.19 MPa to 18.01 MPa. With an increase in the distance <em>S</em> from 0 to 8 mm, the maximum pressure received by the wall gradually decreases from 19.77 MPa to 9.37 MPa. The relationship found between the slow collapse stage (<em>t<sub>a</sub></em>), the second contraction (<em>t<sub>b</sub></em>), and the distance (<em>L</em>) can provide guidance for the effective application of the energy released by bubble collapse.</div></div>","PeriodicalId":8261,"journal":{"name":"Applied Ocean Research","volume":null,"pages":null},"PeriodicalIF":4.3000,"publicationDate":"2024-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Experiments on the effect of wall distances for bubble collapse characteristics\",\"authors\":\"\",\"doi\":\"10.1016/j.apor.2024.104277\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><div>At present, the energy released by bubble collapse can be used for the surface treatment of workpieces and can also be used to degrade pollutants. However, the mechanism of action between bubble collapse and a nearby wall has yet to be accurately explained. In order to grasp the relationship between the wall distance and collapse characteristics, the methods of spark discharge, high-speed photography, and pressure acquisition are used to study bubble shapes and the dynamic variation during pressure release with different wall distances in this paper. The results show that with the increasing of the distance <em>L</em>, the shape of a bubble changes from oblate to spherical and its collapse time shortens. The proportion of the total collapse time consumed by the slow collapse stage shows an increasing trend. In an experiment with two contractions, the time proportion of the slow collapse stage of the first contraction is much larger than that of the second contraction. The existence of the wall delays the collapse of the bubble. As the distance <em>L</em> increases, the bubble goes from undergoing one collapse to two collapses and then to one collapse again. The proportion of the duration of the slow collapse stage of the first contraction decreases rapidly, and the proportion of the slow collapse stage of the second contraction increases slowly, but the time proportion of second contraction decreases. When the distance <em>L</em> increases from 4.5 mm to 11 mm, the pressure received by the wall gradually decreases 28.19 MPa to 18.01 MPa. With an increase in the distance <em>S</em> from 0 to 8 mm, the maximum pressure received by the wall gradually decreases from 19.77 MPa to 9.37 MPa. The relationship found between the slow collapse stage (<em>t<sub>a</sub></em>), the second contraction (<em>t<sub>b</sub></em>), and the distance (<em>L</em>) can provide guidance for the effective application of the energy released by bubble collapse.</div></div>\",\"PeriodicalId\":8261,\"journal\":{\"name\":\"Applied Ocean Research\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":4.3000,\"publicationDate\":\"2024-10-18\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Applied Ocean Research\",\"FirstCategoryId\":\"5\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0141118724003985\",\"RegionNum\":2,\"RegionCategory\":\"工程技术\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"ENGINEERING, OCEAN\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Applied Ocean Research","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0141118724003985","RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"ENGINEERING, OCEAN","Score":null,"Total":0}
引用次数: 0
摘要
目前,气泡坍塌释放的能量可用于工件的表面处理,也可用于降解污染物。然而,气泡塌陷与附近壁面之间的作用机理尚未得到准确解释。为了掌握壁距与塌陷特性之间的关系,本文采用火花放电、高速摄影和压力采集等方法,研究了不同壁距下的气泡形状和压力释放过程中的动态变化。结果表明,随着壁距 L 的增大,气泡的形状由扁圆形变为球形,塌陷时间缩短。缓慢坍缩阶段所消耗的时间占总坍缩时间的比例呈上升趋势。在两次收缩的实验中,第一次收缩的慢速塌缩阶段所占的时间比例远远大于第二次收缩。气泡壁的存在延迟了气泡的坍缩。随着距离 L 的增加,气泡会从一次塌缩变成两次塌缩,然后再变成一次塌缩。第一次收缩的缓慢塌缩阶段的持续时间比例迅速减少,第二次收缩的缓慢塌缩阶段的比例缓慢增加,但第二次收缩的时间比例减少。当距离 L 从 4.5 mm 增加到 11 mm 时,壁面承受的压力逐渐从 28.19 MPa 减小到 18.01 MPa。当距离 S 从 0 毫米增加到 8 毫米时,墙体承受的最大压力从 19.77 兆帕逐渐减小到 9.37 兆帕。缓慢塌陷阶段 (ta)、第二次收缩 (tb) 和距离 (L) 之间的关系可为有效利用气泡塌陷释放的能量提供指导。
Experiments on the effect of wall distances for bubble collapse characteristics
At present, the energy released by bubble collapse can be used for the surface treatment of workpieces and can also be used to degrade pollutants. However, the mechanism of action between bubble collapse and a nearby wall has yet to be accurately explained. In order to grasp the relationship between the wall distance and collapse characteristics, the methods of spark discharge, high-speed photography, and pressure acquisition are used to study bubble shapes and the dynamic variation during pressure release with different wall distances in this paper. The results show that with the increasing of the distance L, the shape of a bubble changes from oblate to spherical and its collapse time shortens. The proportion of the total collapse time consumed by the slow collapse stage shows an increasing trend. In an experiment with two contractions, the time proportion of the slow collapse stage of the first contraction is much larger than that of the second contraction. The existence of the wall delays the collapse of the bubble. As the distance L increases, the bubble goes from undergoing one collapse to two collapses and then to one collapse again. The proportion of the duration of the slow collapse stage of the first contraction decreases rapidly, and the proportion of the slow collapse stage of the second contraction increases slowly, but the time proportion of second contraction decreases. When the distance L increases from 4.5 mm to 11 mm, the pressure received by the wall gradually decreases 28.19 MPa to 18.01 MPa. With an increase in the distance S from 0 to 8 mm, the maximum pressure received by the wall gradually decreases from 19.77 MPa to 9.37 MPa. The relationship found between the slow collapse stage (ta), the second contraction (tb), and the distance (L) can provide guidance for the effective application of the energy released by bubble collapse.
期刊介绍:
The aim of Applied Ocean Research is to encourage the submission of papers that advance the state of knowledge in a range of topics relevant to ocean engineering.