Large-scale particle trapping by acoustic vortices with a continuously variable topological charge  

作　　者：庄昊霏 张清源 胡格昊 王青东 杜立彬 Haofei Zhuang;Qingyuan Zhang;Gehao Hu;Qingdong Wang;Libin Du(College of Ocean Science and Engineering,Shandong University of Science and Technology,Qingdao 266590,China;Department of Radiology,the Affiliated Hospital of Qingdao University,Qingdao 266000,China;College of Electronic and Information Engineering,Shandong University of Science and Technology,Qingdao 266590,China)

机构地区：[1]College of Ocean Science and Engineering,Shandong University of Science and Technology,Qingdao 266590,China [2]Department of Radiology,the Affiliated Hospital of Qingdao University,Qingdao 266000,China [3]College of Electronic and Information Engineering,Shandong University of Science and Technology,Qingdao 266590,China

出　　处：《Chinese Physics B》2024年第7期398-406,共9页中国物理B（英文版）

基　　金：Project supported by the National Key R&D Program of China(Grant No.2023YFE0201900)。

摘　　要：Strengthened directivity with higher-order side lobes can be generated by the transducer with a larger radius at a higher frequency. The multi-annular pressure distributions are displayed in the cross-section of the acoustic vortices(AVs)which are formed by side lobes. In the near field, particles can be trapped in the valley region between the two annuli of the pressure peak, and cannot be moved to the vortex center. In this paper, a trapping method based on a sector transducer array is proposed, which is characterized by the continuously variable topological charge(CVTC). This acoustic field can not only enlarge the range of particle trapping but also improve the aggregation degree of the trapped particles. In the experiments, polyethylene particles with a diameter of 0.2 mm are trapped into the multi-annular valleys by the AV with a fixed topological charge. Nevertheless, by applying the CVTC, particles outside the radius of the AV can cross the pressure peak successfully and move to the vortex center. Theoretical studies are also verified by the experimental particles trapping using the AV with the continuous variation of three topological charges, and suggest the potential application of large-scale particle trapping in biomedical engineering.

关 键 词：acoustic vortices sector transducer array trapping particle continuously variable topological charge 

分 类 号：TB552[理学—物理]