论文标题
软固体气缸的扭转不稳定性
Torsion instability of soft solid cylinders
论文作者
论文摘要
已知将纯扭转在长而细的圆柱杆上的应用会引起扭曲的不稳定性，从初始扭结变成结。在粗短圆柱体的扭转平行板流变体中，几何约束将圆柱体的轴置于零位移，从而阻止了这种扭曲不稳定的发生。在这些实验条件下，皱纹以给定的临界扭转角出现在圆柱体的表面上。在这里，我们通过应用在有限菌株上叠加在有限的弹性变形的理论中，研究了弹性不稳定性的这种弹性不稳定性（称为扭转不稳定性）的扭转不稳定。我们以Stroh差异形式制定了增量边界弹性问题，并使用表面阻抗方法来构建强大的数值程序来推导边际稳定性曲线。我们介绍了Mooney-Rivlin材料的结果，并研究了材料参数对弹性分叉的影响。
The application of pure torsion to a long and thin cylindrical rod is known to provoke a twisting instability, evolving from an initial kink to a knot. In the torsional parallel-plate rheometry of stubby cylinders, the geometrical constraints impose zero displacement of the axis of the cylinder, preventing the occurrence of such twisting instability. Under these experimental conditions, wrinkles occur on the cylinder's surface at a given critical angle of torsion. Here we investigate this subclass of elastic instability--which we call torsion instability--of soft cylinders subject to a combined finite axial stretch and torsion, by applying the theory of incremental elastic deformation superimposed on finite strains. We formulate the incremental boundary elastic problem in the Stroh differential form, and use the surface impedance method to build a robust numerical procedure for deriving the marginal stability curves. We present the results for a Mooney-Rivlin material and study the influence of the material parameters on the elastic bifurcation.
