2026-06-27T10:33:03Zhttps://docta.ucm.es/rest/oai/request

oai:docta.ucm.es:20.500.14352/177102024-09-06T16:56:45Zcom_20.500.14352_14col_20.500.14352_15

Giraudet, Cédric Bataller, Henri Sun, Yifei Donev, Aleksandar Ortiz De Zárate Leira, José María Croccolo, Fabrizio 2023-06-17T21:52:50Z 2023-06-17T21:52:50Z 2016-12-12 1292-8941 10.1140/epje/i2016-16120-8 https://hdl.handle.net/20.500.14352/17710 http://dx.doi.org/10.1140/epje/i2016-16120-8 http://link.springer.com/ In a recent letter (C. Giraudet et al., EPL 111, 60013 (2015)) we reported preliminary data showing evidence of a slowing-down of non-equilibrium fluctuations of the concentration in thermodiffusion experiments on a binary mixture of miscible fluids. The reason for this slowing-down was attributed to the effect of confinement. Such tentative explanation is here experimentally corroborated by new measurements and theoretically substantiated by studying analytically and numerically the relevant fluctuating hydrodynamics equations. In the new experiments presented here, the magnitude of the temperature gradient is changed, confirming that the system is controlled solely by the solutal Rayleigh number, and that the slowing-down is dominated by a combined effect of the driving force of buoyancy, the dissipating force of diffusion and the confinement provided by the vertical extension of the sample cell. Moreover, a compact phenomenological interpolating formula is proposed for easy analysis of experimental results. eng open access Confinement effect on the dynamics of non-equilibrium concentration fluctuations far from the onset of convection journal article