Numerical simulation of the electro-convective onset and complex flows of dielectric liquid in an annulus

• Published in: Journal of mechanical science and technology 2012, 26(12), , pp.3785-3793
• Main Authors: Fernandes, Dolfred Vijay, Lee, Heon-Deok, Alapati, Suresh, Suh, Yong Kweon
• Format: Article
• Language: English
• Subjects: Chaos theory; Computational fluid dynamics; Computational methods in fluid dynamics; Control; Cylinders; Dynamical Systems; Engineering; Exact sciences and technology; Fluid dynamics; Fluid flow; Fundamental areas of phenomenology (including applications); Industrial and Production Engineering; Liquids; Magnetohydrodynamics and electrohydrodynamics; Mathematical analysis; Mathematical models; Mechanical Engineering; Navier-Stokes equations; Physics; Vibration; 기계공학
• ISSN: 1738-494X; 1976-3824
• DOI: 10.1007/s12206-012-1005-3

We conducted a numerical study on the onset of electro-convection as well as the complex flow phenomena of dielectric liquid subjected to unipolar autonomous charge injection in the annular gap between two concentric circular cylindrical electrodes. The Nernst-Planck equations governing the charge density transport, the Poisson equation for the electric potential and the Navier-Stokes equations for the fluid flow are solved numerically using the finite volume method. The developed code is validated by comparing the critical stability parameter values for the onset of electro-convection with those obtained from the linear stability analysis. We identify in a parameter space the stable hydrostatic state and the electro-convection state. The electro-convection is again divided into three regimes: stationary, oscillatory and chaotic. For inner cylinder radius r i ≥ 1.0, we observed an increase in the number of charged plumes and vortex pairs with stability parameter T before the electro-convection becomes chaotic. For outer injection, although the onset of electroconvection starts at T higher than the inner injection, the onset of chaotic motion occurs at lower T .