Interfacial instabilities of a fluid annulus in a rotating Hele-Shaw cell


Autoria(s): Carrillo Galdó, Lluís; Soriano i Fradera, Jordi; Ortín, Jordi, 1959-
Contribuinte(s)

Universitat de Barcelona

Data(s)

04/05/2012

Resumo

We have studied the interfacial instabilities experienced by a liquid annulus as it moves radially in a circular Hele-Shaw cell rotating with angular velocity Omega. The instability of the leading interface (oil displacing air) is driven by the density difference in the presence of centrifugal forcing, while the instability of the trailing interface (air displacing oil) is driven by the large viscosity contrast. A linear stability analysis shows that the stability of the two interfaces is coupled through the pressure field already at a linear level. We have performed experiments in a dry cell and in a cell coated with a thin fluid layer on each plate, and found that the stability depends substantially on the wetting conditions at the leading interface. Our experimental results of the number of fingers resulting from the instability compare well with the predictions obtained through a numerical integration of the coupled equations derived from a linear stability analysis. Deep in the nonlinear regime we observe the emission of liquid droplets through the formation of thin filaments at the tip of outgrowing fingers.

Identificador

http://hdl.handle.net/2445/24906

Idioma(s)

eng

Publicador

American Institute of Physics

Direitos

(c) American Institute of Physics, 2000

info:eu-repo/semantics/openAccess

Palavras-Chave #Mecànica de fluids #Viscositat #Porositat #Fluid mechanics #Viscosity #Porosity
Tipo

info:eu-repo/semantics/article

info:eu-repo/semantics/publishedVersion