Swelling Dynamics of a Disk-Shaped Gel

When a gel absorbs solvent from surrounding, stress field is created in the gel, and this causes complex dynamics of swelling behavior. Here we study effect for disk-shaped by rigorously solving diffusio-mechanical coupling equation. We show that (a) while macroscopic thickness radius increases monotonically time, compressed near mid-plane, (b) time depends on shear modulus $G$ its dependence weak, mainly determined friction constant network osmotic bulk gel. also these characteristic features are reproduced accurately simple variational calculation deformation. An analytical expression given time.