https://doi.org/10.1140/epjst/e2016-60234-4
Regular Article
Thin-film Faraday patterns in three dimensions
Department of Theoretical Physics, Brandenburg University of Technology, 03044 Cottbus, Germany
a e-mail: sebastian.richter@b-tu.de
Received: 20 July 2016
Revised: 16 August 2016
Published online: 2 May 2017
We investigate the long time evolution of a thin fluid layer in three spatial dimensions located on a horizontal planar substrate. The substrate is subjected to time-periodic external vibrations in normal and in tangential direction with respect to the plane surface. The governing partial differential equation system of our model is obtained from the incompressible Navier-Stokes equations considering the limit of a thin fluid geometry and using the long wave lubrication approximation. It includes inertia and viscous friction. Numerical simulations evince the existence of persistent spatially complex surface patterns (periodic and quasiperiodic) for certain superpositions of two vertical excitations and initial conditions. Additional harmonic lateral excitations cause deformations but retain the basic structure of the patterns. Horizontal ratchet-shaped forces lead to a controllable lateral movement of the fluid. A Floquet analysis is used to determine the stability of the linearized system.
© EDP Sciences, Springer-Verlag, 2017