Nonlinear square patterns in Rayleigh-Bénard convection

We numerically investigate nonlinear asymmetric square patterns in a horizontal convection layer with up-down reflection symmetry. As a novel feature we find the patterns to appear via the skewed varicose instability of rolls. The time-independent nonlinear state is generated by two unstable checkerboard (symmetric square) patterns and their nonlinear interaction. As the bouyancy forces increase, the interacting modes give rise to bifurcations leading to a periodic alternation between a nonequilateral hexagonal pattern and the square pattern or to different kinds of standing oscillations.

Metadaten
Author details:	Ayhan Demircan, Norbert Seehafer ORCiD
URN:	urn:nbn:de:kobv:517-opus-14986
Publication series (Volume number):	NLD Preprints (62)
Publication type:	Preprint
Language:	English
Publication year:	2000
Publishing institution:	Universität Potsdam
Release date:	2007/08/15
Organizational units:	Zentrale und wissenschaftliche Einrichtungen / Interdisziplinäres Zentrum für Dynamik komplexer Systeme
DDC classification:	5 Naturwissenschaften und Mathematik / 53 Physik / 530 Physik
PACS classification:	40.00.00 ELECTROMAGNETISM, OPTICS, ACOUSTICS, HEAT TRANSFER, CLASSICAL MECHANICS, AND FLUID DYNAMICS / 47.00.00 Fluid dynamics (for fluid dynamics of quantum fluids, see section 67; see also section 83 Rheology; for sound generation by fluid flow, see 43.28.Ra-in Acoustics Appendix) / 47.20.-k Flow instabilities (see also 47.15.Fe Stability of laminar flows) / 47.20.Bp Buoyancy-driven instabilities (e.g., Rayleigh-Benard)
	40.00.00 ELECTROMAGNETISM, OPTICS, ACOUSTICS, HEAT TRANSFER, CLASSICAL MECHANICS, AND FLUID DYNAMICS / 47.00.00 Fluid dynamics (for fluid dynamics of quantum fluids, see section 67; see also section 83 Rheology; for sound generation by fluid flow, see 43.28.Ra-in Acoustics Appendix) / 47.20.-k Flow instabilities (see also 47.15.Fe Stability of laminar flows) / 47.20.Ky Nonlinearity, bifurcation, and symmetry breaking