||CMC: Computers, Materials, & Continua, Vol. 12, No. 1, pp. 39-56, 2009
||Full length paper in PDF format. Size = 547,451 bytes
||hydrogel, chemo-mechanical coupling, constitutive equations, variational principle, coupled FE method
||Coupling and interaction of multi-physical fields exist in hydrogel consisting of a fluid and a solid under external stimulus. In this paper, a phenomenological theory for chemo-mechanical coupling behavior and finite element formulation are developed, based on the thermodynamic laws. The free energy function is constructed and used to derive the constitutive equations and governing equations for a linear coupling system including a chemical effect. Equivalent integral forms of the governing equations and coupled finite element equations are obtained by a variational principle. Numerical examples demonstrate the interaction of chemical and mechanical effects of hydrogel under external force loadings and chemical stimuli. It is shown that the chemo-mechanical coupling behavior of hydrogel can be described by the theory and numerical method presented in this paper.