Orientational order and instabilities in suspensions of self-locomoting rods.
نویسندگان
چکیده
The orientational order and dynamics in suspensions of self-locomoting slender rods are investigated numerically. In agreement with previous theoretical predictions, nematic suspensions of swimming particles are found to be unstable at long wavelengths as a result of hydrodynamic fluctuations. Nevertheless, a local nematic ordering is shown to persist over short length scales and to have a significant impact on the mean swimming speed. The consequences of the large-scale orientational disorder for particle dispersion are also discussed.
منابع مشابه
Hydrodynamic fluctuations and instabilities in ordered suspensions of self-propelled particles.
We construct the hydrodynamic equations for suspensions of self-propelled particles (SPPs) with spontaneous orientational order, and make a number of striking, testable predictions: (i) Nematic SPP suspensions are always absolutely unstable at long wavelengths. (ii) SPP suspensions support novel propagating modes at long wavelengths, coupling orientation, flow, and concentration. (iii) In a wav...
متن کاملBrownian dynamics simulations of the self- and collective rotational diffusion coefficients of rigid long thin rods.
Recently a microscopic theory for the dynamics of suspensions of long thin rigid rods was presented, confirming and expanding the well-known theory by Doi and Edwards [The Theory of Polymer Dynamics (Clarendon, Oxford, 1986)] and Kuzuu [J. Phys. Soc. Jpn. 52, 3486 (1983)]. Here this theory is put to the test by comparing it against computer simulations. A Brownian dynamics simulation program wa...
متن کاملMeasuring the nematic order of suspensions of colloidal fd virus by x-ray diffraction and optical birefringence.
The orientational distribution function of the nematic phase of suspensions of the semiflexible rodlike virus fd is measured by x-ray diffraction as a function of concentration and ionic strength. X-ray diffraction from a single-domain nematic phase of fd is influenced by interparticle correlations at low angle, while only intraparticle scatter contributes at high angle. Consequently, the angul...
متن کاملCollective chemotactic dynamics in the presence of self-generated fluid flows.
In microswimmer suspensions locomotion necessarily generates fluid motion, and it is known that such flows can lead to collective behavior from unbiased swimming. We examine the complementary problem of how chemotaxis is affected by self-generated flows. A kinetic theory coupling run-and-tumble chemotaxis to the flows of collective swimming shows separate branches of chemotactic and hydrodynami...
متن کاملInhomogeneous suspensions of rigid rods in flow
An expression for the divergence of the stress tensor is derived for inhomogeneous suspensions of very long and thin, rigid rods. The stress tensor is expressed in terms of the suspension flow velocity and the probability density function for the position and orientation of a rod. The expression for the stress tensor includes stresses arising from possibly very large spatial gradients in the sh...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
- Physical review letters
دوره 99 5 شماره
صفحات -
تاریخ انتشار 2007