Abstract
A boundary-value problem is formulated describing the shapes of inflated and deflated axisymmetric capsules enclosed by elastic membranes. When the membrane tension is isotropic and the principal bending moments obey constitutive equations involving the principal curvatures in the reference and deformed state but not the stretch ratios, the capsule shape is governed by a third-order ordinary differential equation for the meridional curvature involving the difference between the internal and external pressure. Numerical solutions of the boundary-value problem illustrate the shape of deflated spherical capsules enclosed by incompressible membranes and the shape of inflated and deflated biconcave capsules resembling red blood cells. The results demonstrate that the solution space of deformed spherical capsules consists of bifurcating branches arising at a sequence of transmural pressures, and illustrate the pressure developing inside spherical and biconcave capsules when a certain amount of fluid has been injected into, or withdrawn from, the interior.
Similar content being viewed by others
References
E. A. Evans and R. Skalak, Mechanics and Thermodynamics of Biomembranes. Boca Raton, Florida: CRC Press (1980) 254 pp.
Y. C. Fung, Biodynamics: Circulation. New York: Springer-Verlag (1984) 404 pp.
C. Pozrikidis, Effect of bending stiffness on the deformation of liquid capsules in simple shear flow. J. Fluid Mech. 440 (2001) 269–291.
P. R. Zarda, S. Chien and R. Skalak, Elastic deformations of red blood cells. J. Biomech. 10 (1977) 211–221.
C. Pozrikidis, Introduction to Theoretical and Computational Fluid Dynamics. New York: Oxford University Press (1997) 627 pp.
H. Møllmann, Introduction to the Theory of Thin Shells. New York: John Wiley & Sons (1981) 181 pp.
C. Pozrikidis, Numerical Computation in Science and Engineering. New York: Oxford University Press (1998) 675 pp.
E. A. Evans and Y. C. Fung, Improved measurements of the erythrocyte geometry. Macrovasc. Res. 4 (1972) 335–347.
E. Reissner, On the theory of thin elastic shells. In: Contributions to Applied Mechanics, H. Reissner Anniversary volume. Ann Arbor: J.W. Edwards (1949) 231–247.
E. Reissner, On axisymmetrical deformations of thin shells of revolution, proceedings. In: Third Symposium in Applied Mathematics. New York: McGraw Hill (1950) 27–52.
E. Reissner, On the equations for finite symmetrical deflections of thin shells of revolution. In: Progress in Applied Mechanics, Prager Anniversary Volume. New York: McMillan (1963) 171–178.
E. Reissner, On finite symmetrical deflections of thin shells of revolution. J. Appl. Mech. 36, Trans. ASME 91 Series E (1969) 267–270.
D. J. Steigmann, Fluid films with curvature elasticity. Arch. Rat. Mech. 150 (1999) 127–152.
D. J. Steigmann and R. W. Ogden, Plane deformations of elastic solids with intrinsic boundary elasticity. Proc. R. Soc. London A 453 (1997) 853–877.
D. J. Steigmann and R. W. Ogden, Elastic surface-substrate interactions. Proc. R. Soc. London A 455 (1999) 427–474.
J. E. Flaherty, J. B. Keller and S. I. Rubinow, Post-buckling behavior of elastic tubes and rings with opposite sides in contact. SIAM J. Appl. Math. 23 (1972) 446–455.
C. Pozrikidis, Buckling and collapse of open and closed cylindrical shells. J. Eng. Math. 42 (1992) 157–180.
N. Yamaki, Elastic Stability of Circular Cylindrical Shells. New York: North-Holland (1984) 558 pp.
R. Skalak, A. Tözeren, P. R. Zarda and S. Chien, Strain energy function of red blood cell membranes. Biophys. J. 13 (1973) 245–264.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Pozrikidis, C. Deformed shapes of axisymmetric capsules enclosed by elastic membranes. Journal of Engineering Mathematics 45, 169–182 (2003). https://doi.org/10.1023/A:1022154201045
Issue Date:
DOI: https://doi.org/10.1023/A:1022154201045