| 摘要: | 摘要： We prove that, for an object with a finitefold rotational symmetry (except for a twofold one) around an axis and mirror symmetries (such as a square rod or pentagonal slab, etc.), dynamics of the symmetry axis in low Reynolds number shear flow exactly follows the same form as that of a uniaxial object (e.g., a circular rod or symmetric ellipsoid) as the so-called Jeffery orbits. We use the formulation in which the dynamics of the rigid body follows first-order ordinary differential equations in time [Phys. Rev. E 84, 056309 (2011)]. Interaction between the object and the shear flow enters through a set of scalar coefficients, and the flow field does not need to be solved dynamically. Results of numerical simulations for general-shaped objects also are discussed. In the second part, Brownian dynamics of a uniaxial object is studied numerically. With D as the rotational diffusion constant, α as a parameter characterizing the aspect ratio, and γ as the shear rate, the object starts to align with the flow when the value of D/(γα) decreases near 1. At large α (the long object limit), the results suggest much lower flow alignment when D/(γα)>1.
其他題名： Phys Rev E Stat Nonlin Soft Matter Phys
出版者： United States
出版日期： 2013-12
出處： Physical review. E, Statistical, nonlinear, and soft matter physics, 2013-12, Vol.88 (6), p.063006, Article 063006
識別號： ISSN: 1539-3755
識別號： ISSN: 1550-2376
識別號： EISSN: 1550-2376
識別號： DOI: 10.1103/PhysRevE.88.063006
識別號： PMID: 24483556 |
