气候变化领域集成服务门户(CCPortal): Flow-induced phase separation of active particles is controlled by boundary conditions

CCPortal

DOI	10.1073/pnas.1718807115
	Flow-induced phase separation of active particles is controlled by boundary conditions
	Thutupalli S.; Geyer D.; Singh R.; Adhikari R.; Stone H.A.
发表日期	2018
ISSN	0027-8424
起始页码	5403
结束页码	5408
卷号	115 期号:21
英文摘要	Active particles, including swimming microorganisms, autophoretic colloids, and droplets, are known to self-organize into ordered structures at fluid–solid boundaries. The entrainment of particles in the attractive parts of their spontaneous flows has been postulated as a possible mechanism underlying this phenomenon. Here, combining experiments, theory, and numerical simulations, we demonstrate the validity of this flow-induced ordering mechanism in a suspension of active emulsion droplets. We show that the mechanism can be controlled, with a variety of resultant ordered structures, by simply altering hydrodynamic boundary conditions. Thus, for flow in Hele–Shaw cells, metastable lines or stable traveling bands can be obtained by varying the cell height. Similarly, for flow bounded by a plane, dynamic crystallites are formed. At a no-slip wall, the crystallites are characterized by a continuous out-of-plane flux of particles that circulate and re-enter at the crystallite edges, thereby stabilizing them. At an interface where the tangential stress vanishes, the crystallites are strictly 2D, with no out-of-plane flux. We rationalize these experimental results by calculating, in each case, the slow viscous flow produced by the droplets and the long-ranged, many-body active forces and torques between them. The results of numerical simulations of motion under the action of the active forces and torques are in excellent agreement with experiments. Our work elucidates the mechanism of flow-induced phase separation in active fluids, particularly active colloidal suspensions, and demonstrates its control by boundaries, suggesting routes to geometric and topological phenomena in an active matter. © 2018 National Academy of Sciences. All rights reserved.
英文关键词	Active matter; Boundary effects; Hydrodynamics; Phase separation
语种	英语
scopus关键词	Article; colloid; controlled study; emulsion; flow kinetics; fluid flow; force; hydrodynamics; mathematical model; phase separation; priority journal; torque; viscosity
来源期刊	Proceedings of the National Academy of Sciences of the United States of America
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/160512
作者单位	Thutupalli, S., Simons Centre for the Study of Living Machines, National Centre for Biological Sciences, Bangalore, 560065, India, International Centre for Theoretical Sciences, Tata Institute of Fundamental Research, Bangalore, 560012, India, Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, NJ 08544, United States, Joseph Henry Laboratories of Physics, Princeton University, Princeton, NJ 08544, United States; Geyer, D., Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, NJ 08544, United States; Singh, R., Department of Theoretical Physics, Institute of Mathematical Sciences, Homi Bhabha National Institute, Chennai, 600113, India, Department of Applied Mathematics and Theoretical Physics, Centre for Mathematical Sciences, University of Cambridge, Cambridge, CB3 0WA, United Kingdom; Adhikari, R., Department of Theoretical Physics, Institute of Mathematical Sciences, Homi Bhabha National Institute, Chennai, 600113, India, Department of...
推荐引用方式 GB/T 7714	Thutupalli S.,Geyer D.,Singh R.,et al. Flow-induced phase separation of active particles is controlled by boundary conditions[J],2018,115(21).
APA	Thutupalli S.,Geyer D.,Singh R.,Adhikari R.,&Stone H.A..(2018).Flow-induced phase separation of active particles is controlled by boundary conditions.Proceedings of the National Academy of Sciences of the United States of America,115(21).
MLA	Thutupalli S.,et al."Flow-induced phase separation of active particles is controlled by boundary conditions".Proceedings of the National Academy of Sciences of the United States of America 115.21(2018).