Numerical and Experimental Analysis of the Motion of a Hyperelastic Body in a Fluid

In this study, a numerical algorithm is developed for simulating the interaction between a fluid and a ۲D/axisymmetric hyperelastic body based on a full Eulerian fluid-structure interaction (FSI) method. In this method, the solid volume fraction is used for describing the multi component material and the deformation tensor for describing the deformation of the hyperelastic body. The constitutive law in the Cauchy stress form and an equation are used for the transport of the deformation tensor field which are the core elements of the simulation method. For materials with a low stiffness, an explicit formulation is used for the elastic stress. In some cases, however, due to high stiffness asemi implicit formulation is used for the elastic stress to avoid instability. The strain rate has a discontinuity across the fluid-body interface. For improving accuracy in capturing the interface, solid is treated as a highly viscous fluid. An experimental setup is used to validate the numerical results. The movement of a sphere made of silicone in air and its impact on a rigid surface are investigated. A high speed Charge-Coupled Device (CCD) camera is used to capture images and image processing techniques are employed to obtain the required data from images. For all cases considered, the results are in good agreement with those of the experiment performed in this study and other numericalresults reported in the literature.

Keywords:

Fluid Solid Interaction , Hyperelastic Material , Implicit Elastic Term , Image Processing