Quincke rotation driven flows

2020 ◽  
Vol 5 (1) ◽  
Author(s):  
M. Belovs ◽  
A. Cēbers
Keyword(s):  
2016 ◽  
Vol 788 ◽  
Author(s):  
Ehud Yariv ◽  
Itzchak Frankel

When subject to sufficiently strong electric fields, particles and drops suspended in a weakly conducting liquid exhibit spontaneous rotary motion. This so-called Quincke rotation is a fascinating example of nonlinear symmetry-breaking phenomena. To illuminate the rotation of liquid drops we here analyse the asymptotic limit of large electric Reynolds numbers, $\mathit{Re}\gg 1$, within the framework of a two-dimensional Taylor–Melcher electrohydrodynamic model. A non-trivial dominant balance in this singular limit results in both the fluid velocity and surface-charge density scaling as $\mathit{Re}^{-1/2}$. The flow is governed by a self-contained nonlinear boundary-value problem that does not admit a continuous fore–aft symmetric solution, thus necessitating drop rotation. Furthermore, thermodynamic arguments reveal that a fore–aft asymmetric solution exists only when charge relaxation within the suspending liquid is faster than that in the drop. The flow problem possesses both mirror-image (with respect to the direction of the external field) and flow-reversal symmetries; it is transformed into a universal one, independent of the ratios of electric conductivities and dielectric permittivities in the respective drop phase and suspending liquid phase. The rescaled angular velocity is found to depend weakly upon the viscosity ratio. The corresponding numerical solutions of the exact equations indeed collapse at large $\mathit{Re}$ upon the asymptotically calculated universal solution.


2002 ◽  
Vol 16 (17n18) ◽  
pp. 2603-2609 ◽  
Author(s):  
A. CEBERS ◽  
E. LEMAIRE ◽  
L. LOBRY

When particles immersed in a semi-insulating liquid are submitted to a sufficiently high DC field, they can rotate spontaneously around any axis perpendicular to the field (Quincke rotation). Recently we have shown that due to Quincke effect the effective viscosity of a colloidal suspension could be reduced. When the suspension is submitted to a shear, the particles rotation is amplified by the electric torque and drives the suspending liquid. For a flow in a capillary, this effect manifests itself by an increase of the flow rate. We present the results of our experiments carried out with a rectangular cross section capillary. These results are compared with the direct determination of the apparent viscosity in a Couette flow rheometer.


Author(s):  
А.И. Грачев

AbstractImplementation of the well-known phenomenon of Quincke rotation is proposed, which may be called the “photoinduced Quincke rotation (PIQR) effect.” The PIQR effect is based on the previously discovered phenomenon of rotation of a spherical particle in a stationary electric field under continuous irradiation inducing an electric dipole moment in the particle.


Author(s):  
А.И. Грачев

Opportunity to observe magnetic analog of the Quincke rotation effect, namely, spontaneous rotation of a spherical particle in homogeneous DC magnetic field (B), is analyzed. Two experimental versions: nonmagnetic particle suspensioned in ferromagnetic liquid and, second, - diamagnetic sphere levitated in vacuum, are considered. In the first case spontaneous rotation is possible in the fields B < 0.1 T for relaxation times of the particle magnetization ~ 10-3 s. Indispensible condition of accelerated spinning of the diamagnetic sphere is confinement of its rotation degree of freedom by only one rotation axis orthogonal to the vector B.


1984 ◽  
Vol IA-20 (4) ◽  
pp. 845-849 ◽  
Author(s):  
Thomas B. Jones
Keyword(s):  

Sign in / Sign up

Export Citation Format

Share Document