Hostname: page-component-f554764f5-246sw Total loading time: 0 Render date: 2025-04-13T12:21:35.711Z Has data issue: false hasContentIssue false
  • English
  • Français

Experimental studies of the deformation and breakup of a synthetic capsule in steady and unsteady simple shear flow

Published online by Cambridge University Press:  26 April 2006

K. S. Chang  and
W. L. Olbricht
K. S. Chang
Affiliation:
School of Chemical Engineering, Cornell University, Ithaca, NY 14853, USA Present address: Kimberly-Clark, 2100 Winchester Road, Neenah, WI 54957-0999, USA.
W. L. Olbricht
Affiliation:
School of Chemical Engineering, Cornell University, Ithaca, NY 14853, USA
Get access Rights & Permissions [Opens in a new window]

Abstract

An experimental study is reported of the motion, deformation, and breakup of a synthetic capsule that is freely suspended in Couette flow. The capsule is a liquid drop surrounded by a thin polymeric membrane. The shape and orientation of the capsule are measured in steady flow and following the start-up of Couette flow. Results are compared with predictions of the small-deformation theory of Barthes-Biesel and co-workers. The data suggest that the capsule membrane is viscoelastic, and comparisons with theory yield values of the membrane elastic modulus and the membrane viscosity. The values of the elastic modulus of the capsule membrane deduced from the flow data are compared with independent measurements for the same capsule.

When the flow-induced deformation becomes sufficiently large, the capsules break. Breakup begins at points on the membrane surface near the principal strain axis of the undisturbed flow. By examining the local deformation within the membrane, it is shown that breakup is correlated with local thinning of the membrane and is initiated at points where the thickness is a minimum.

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 250 , May 1993 , pp. 609 - 633
Copyright
© 1993 Cambridge University Press

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Article purchase

Temporarily unavailable

References

Barthes-Biesel, D. 1991 Role of interfacial properties on the motion and deformation of capsules in shear flow. Physica A 172, 103–124.Google Scholar
Barthes-Biesel, D. & Sgaier, H. 1985 Role of membrane viscosity in the orientation and deformation of a spherical capsule suspended in simple shear flow. J. Fluid Mech. 160, 119–135.Google Scholar
Chang, K. S. 1991 Experimental study of capsule motion and deformation in linear shear flows. PhD thesis, Cornell University.
Chang, K. S. & Olbricht, W. L. 1993 Experimental studies of the deformation of a synthetic capsule in extensional flow. J. Fluid Mech. 250, 587–608.Google Scholar
Feng, W. W. & Yang, W. H. 1973 On the contact problem of an inflated spherical nonlinear membrane. Trans. ASME E: J. Appl. Mech. 40, 209–214.Google Scholar
Goldsmith, H. L. & Marlow, J. 1972 Flow behavior of erythrocytes. I. Rotation and deformation in dilute suspensions. Proc. R. Soc. Lond. B 182, 351–384.Google Scholar
Keller, S. R. & Skalak, R. 1982 Motion of a tank-treading ellipsoidal particle in a shear flow. J. Fluid Mech. 120, 27–47.Google Scholar
Lardner, T. J. & Pujara, P. 1977 Analysis of deformations of cell membranes. In Proc. the Biomechanics Symp. Yale Univ., AMP 23 New Haven, Ct, pp. 65–67.
Lardner, T. J. & Pujara, P. 1978 On the contact problem of a highly inflated spherical nonlinear membrane. Trans. ASME E: J. Appl. Mech. 45, 202–203.Google Scholar
Lardner, T. J. & Pujara, P. 1980 Compression of spherical cells. Mech. Today 5, 161–176.Google Scholar
Li, X. Z., Barthes-Biesel, D. & Helmy, A. 1988 Large deformations and burst of a capsule freely suspended in an elongational flow. J. Fluid Mech. 187, 179–196.Google Scholar
Rodriguez, F. 1982 Principles of Polymer Systems. McGraw-Hill.
Schmid-Schönbein, H. & Wells, R. 1969 Fluid drop-like transition of erythrocytes under shear. Science 165, 288–291.Google Scholar