標題: Analytical study for swimmers in a channel
作者: Farutin, A.
Wu, H.
Hu, W-F
Rafai, S.
Peyla, P.
Lai, M-C
Misbah, C.
應用數學系
Department of Applied Mathematics
關鍵字: swimming/flying;micro-organism dynamics
公開日期: 25-十二月-2019
摘要: There is an overabundance of microswimmers in nature, including bacteria, algae, mammalian cells and so on. They use flagellum, cilia or global shape changes (amoeboid motion) to move forward. In the presence of confining channels, these swimmers exhibit often non-trivial behaviours, such as accumulation at the wall, navigation and so on, and their swimming speed may be strongly influenced by the geometric confinement. Several numerical studies have reported that the presence of walls either enhances or reduces the swimming speed depending on the nature of the swimmer, and also on the confinement. The purpose of this paper is to provide an analytical explanation of several previously obtained numerical results. We treat the case of amoeboid swimmers and the case of squirmers having either a tangential (the classical situation) or normal velocity prescribed at the swimmer surface (pumper). For amoeboid motion we consider a quasi-circular swimmer which allows us to tackle the problem analytically and to extract the equations of the motion of the swimmer, with several explicit analytical or semi-analytical solutions. It is found that the deformation of the amoeboid swimmer as well as a high enough order effect due to confinement are necessary in order to account for previous numerical results. The analytical theory accounts for several features obtained numerically also for non-deformable swimmers.
URI: http://dx.doi.org/10.1017/jfm.2019.751
http://hdl.handle.net/11536/153501
ISSN: 0022-1120
DOI: 10.1017/jfm.2019.751
期刊: JOURNAL OF FLUID MECHANICS
Volume: 881
起始頁: 365
結束頁: 383
顯示於類別:期刊論文