2003/03/31 by Cheng Yang, Yang, Cheng
Engineering · Physics and Astronomy · #Characterization and Applications of Magnetic Nanoparticles #Electrohydrodynamics and Fluid Dynamics #FOS: Physical sciences #Fluid Dynamics (physics.flu-dyn) #Micro and Nano Robotics #physics.flu-dyn
paper · pdf · doi:10.48550/arxiv.physics/0303122
4 pages, 5 figures
arxiv created 2003/03/31 · openalex publication_date 2003/03/31 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We use boundary-integral methods to compute the time-dependent deformation of a drop of dielectric fluid immersed in another dielectric fluid in a uniform electric field E. Steady state theory predicts, when the permittivity ratio, β, is large enough, a conical interface can exist at two cone angles, with θ_(β) unstable. Our numerical evidence instead shows a dynamical process which produces a cone-formation and a transient finite-time singularity, when E and βare above their critical values. Based on a scaling analysis of the electric stress and the fluid motion, we are able to apply approximate boundary conditions to compute the evolution of the tip region. We find in our non-equilibrium case where the electric stress is substantially larger than the surface tension, the ratio of the electric stress to the surface tension in the newly-grown cone region can converge to a βdependent value, αc(β)>1, while the cone angle converges to θ_