Numerical and Experimental Analysis of the Fluid Structure Interaction in Presence of a Hyperelastic Body

Abstract

In this study, a numerical algorithm is developed for simulating the interaction between a fluid and a 2D/axisymmetric hyperelastic body based on a full Eulerian fluidstructure interaction (FSI) method. In this method, the solid volume fraction is used for describing the multicomponent material and the deformation tensor for describing the deformation of the hyperelastic body. The core elements of the simulation method are the constitutive law in the Cauchy stress form and an equation for the transport of the deformation tensor field. A semiimplicit formulation is used for the elastic stress to avoid instability especially for solid with high stiffness. The strain rate has a discontinuity across the fluid/solid interface. For improving the accuracy in capturing the interface, solid is treated as a highly viscous fluid. The viscosity term has the effect of smoothing the velocity and keeping the simulation stable. 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 substrate are investigated. The images are captured using a high speed CCD camera and the image processing technique is employed to obtain the required data from the images. For all cases considered, the results are in good agreement with those of the experiment performed in this study and other numerical results reported in the literature.