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Experimental study of two interacting drops in an immiscible fluid

Published online by Cambridge University Press:  26 April 2006

Xiaoguang Zhang ,
Robert H. Davis  and
Mark F. Ruth
Xiaoguang Zhang
Affiliation:
Department of Chemical Engineering, University of Colorado, Boulder, CO 80309-0424, USA
Robert H. Davis
Affiliation:
Department of Chemical Engineering, University of Colorado, Boulder, CO 80309-0424, USA
Mark F. Ruth
Affiliation:
Department of Chemical Engineering, University of Colorado, Boulder, CO 80309-0424, USA
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Abstract

Experiments were performed in order to elucidate the effects of hydrodynamic interactions between two drops on their gravity-induced relative motion. The relative trajectories of two drops, their relative velocities, and the travel time for them to flow around each other were measured for different initial horizontal separations. Two size ratios and two viscosity ratios were investigated. Hydrodynamic interactions significantly reduce the relative velocity of two nearby drops and cause them to flow around each other with curved trajectories, resulting in a longer duration of the close encounter, compared with that for two non-interacting drops. These effects increase with decreasing drop separation, decreasing size ratio, and increasing viscosity ratio. Experimental results are in good agreement with theoretical predictions, except when the drops become sufficiently close that interface deformation occurs.

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 249 , April 1993 , pp. 227 - 239
Copyright
© 1993 Cambridge University Press

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