论文标题
脱水后的水凝胶管的圆周屈曲
Circumferential buckling of a hydrogel tube emptying upon dehydration
论文作者
论文摘要
圆柱水凝胶管完全浸入水中，通过肿胀和填充其内部腔来进行水合。当它与空气接触时，它会脱水：该管从墙壁上排出溶剂，收缩。这种脱水过程会导致管腔凹陷，从而导致弯曲的屈曲。在这里，我们使用连续模型研究了这种屈曲的发生，该模型将非线性弹性与Flory-Rehner理论相结合，以考虑到水凝胶的大变形和主动行为。在准静态近似中，我们使用扩展到化学机械方程的增量变形形式主义，以确定触发屈曲的封闭体积的阈值。发现此临界值取决于壳厚度，化学势和本构特征。获得的结果与完整动态问题的有限元模拟的结果非常吻合。
A cylindrical hydrogel tube, completely submerged in water, hydrates by swelling and filling its internal cavity. When it comes back into contact with air, it dehydrates: the tube thus expels the solvent through the walls, shrinking. This dehydration process causes a depression in the tube cavity, which can lead to circumferential buckling. Here we study the occurrence of such buckling using a continuous model that combines non-linear elasticity with Flory-Rehner theory, to take into account both the large deformations and the active behavior of the hydrogel. In quasi-static approximation, we use the incremental deformation formalism, extended to the chemo-mechanical equations, to determine the threshold value of the enclosed volume at which buckling is triggered. This critical value is found to depend on the shell thickness, chemical potential and constitutive features. The results obtained are in good agreement with the results of the finite element simulations of the complete dynamic problem.
