Issue
EPL
Volume 86, Number 1, April 2009
Article Number 16003
Number of page(s) 6
Section Condensed Matter: Structural, Mechanical and Thermal Properties
DOI http://dx.doi.org/10.1209/0295-5075/86/16003
Published online 16 April 2009
EPL, 86 (2009) 16003
DOI: 10.1209/0295-5075/86/16003

Phase transition under forced vibrations in critical CO2

D. Beysens1, 2, Y. Garrabos3, D. Chatain2 and P. Evesque4

1   ESEME, Ecole Supérieure de Physique et Chimie Industrielle, Laboratoire de Physique et Mécanique des Milieux Hétérogènes - 10, rue Vauquelin, 75231 Paris Cedex 05, France, EU
2   ESEME, Institut de Chimie de la Matière Condensée de Bordeaux, UPR 9048 CNRS, Université Bordeaux 1 87, avenue du Docteur A. Schweitzer, 33608 Pessac Cedex, France, EU
3   ESEME, Service des Basses Températures, INAC, CEA-Grenoble - Grenoble, France, EU
4   Lab MSSMat, Ecole Centrale de Paris, UMR 8579 CNRS - 92295 Châtenay-Malabry Cedex, France, EU

daniel.beysens@espci.fr

received 24 February 2009; accepted in final form 6 March 2009; published April 2009
published online 16 April 2009

Abstract
Phase separation is investigated in CO2 under linear harmonic vibrations. The study is performed under weightlessness in a sounding rocket. The fluid is at critical density near its critical point to get benefit from universal behavior. Without vibration, phase separation is characterized by an interconnected pattern of vapor and liquid domains and a near linear growth law. Under vibration, three time regions have been identified. i) When the liquid-vapor domains are smaller than a few viscous boundary layer thickness, growth is unaffected by vibration. ii) Then the Bernoulli pressure across the interfaces makes the domains grow exponentially perpendicularly to the vibration direction while growth parallel to the vibration direction is unaffected. iii) When the domains reach the sample size, the pattern looks as periodic stripes perpendicular to the vibration direction and keep on growing parallel to the vibration direction. A theoretical approach of these phenomena is proposed.

PACS
68.35.Rh - Phase transitions and critical phenomena.
64.60.-i - General studies of phase transitions.
64.70.F- - Liquid-vapor transitions.

© EPLA 2009