Convection in a colloidal suspension with a large negative separation ratio ? is studied experimentally by heating from above. Shadowgraph observations at very large solutal Rayleigh numbers R~ are reported as a function of time. Fast relaxation oscillations are reported for the root mean square value of the shadowgraph intensity. While pure fluids exhibit a transition to turbulent convection for Rayleigh number R?106, stable spoke-pattern planform with up and down columnar flows are observed up to R~?1.9×109. It is suggested that the surprising stability of the planform against turbulence is due to nonlinear focusing arising from the concentration dependence of the diffusion coefficient.
Soret driven convection in a colloidal solution heated from above at very large solutal Rayleigh number / R. Cerbino, A. Vailati, M. Giglio. - In: PHYSICAL REVIEW E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS. - ISSN 1539-3755. - 66:5 pt 2(2002), p. 055301.055301.
|Titolo:||Soret driven convection in a colloidal solution heated from above at very large solutal Rayleigh number|
CERBINO, ROBERTO (Primo)
VAILATI, ALBERTO (Secondo)
GIGLIO, MARZIO (Ultimo)
|Parole Chiave:||convection ; Soret effect ; binary mixture|
|Settore Scientifico Disciplinare:||Settore FIS/03 - Fisica della Materia|
|Data di pubblicazione:||2002|
|Digital Object Identifier (DOI):||http://dx.doi.org/10.1103/PhysRevE.66.055301|
|Appare nelle tipologie:||01 - Articolo su periodico|