https://web.stanford.edu/~borja/pub/cmame2004(2).pdf

Dynamics of porous media at finite strain

Bibliography Computational GeoMechanics

Investigation of impact resistance performance of pyramid lattice sandwich structure based on SPH-FEM

Finite element analysis is an effective tool to evaluate the material properties of living tissue. For an interactive optimization procedure, the finite element analysis usually needs many simulations to reach a reasonable solution. The meta-model analysis of finite element simulation can be used to reduce the computation of a structure with complex geometry or a material with composite constitutive equations. The intervertebral disc is a complex, heterogeneous, and hydrated porous structure. A poroelastic finite element model can be used to observe the fluid transferring, pressure deviation, and other properties within the disc. Defining reasonable poroelastic material properties of the anulus fibrosus and nucleus pulposus is critical for the quality of the simulation. We developed a material property updating protocol, which is basically a fitting algorithm consisted of finite element simulations and a quadratic response surface regression. This protocol was used to find the material properties, such as...

A meta-model analysis of a finite element simulation for defining poroelastic properties of intervertebral discs.

In this work, the authors present an artificial compressibility (AC) version of the characteristic-based split (CBS) algorithm for the numerical solution of flow through a fluid-saturated porous medium In this study, a fully matrix-inversion-free version of the CBS algorithm is used for the first time to solve the generalized porous medium flow equations for forced-, free-, and mixed-convection problems The efficiency, the accuracy, and the steady-state convergence of the AC-CBS algorithm are verified through comparison with numerical and analytical solutions available in the literature The advantages of the proposed AC-CBS scheme include easy parallelization and implementation procedure

Artificial Compressibility-Based CBS Scheme for the Solution of the Generalized Porous Medium Model

Smoothed particle hydrodynamics (SPH) and the finite element method (FEM) are often combined with the scope to model the interaction between structures and the surrounding fluids (FSI). There is the case, for instance, of aircrafts crashing on water or speedboats slamming into waves. Due to the high computational complexity, the influence of air is often neglected, limiting the analysis to the interaction between structure and water. On the contrary, this work aims to specifically investigate the effect of air when merged inside the fluid-structure interaction (FSI) computational models. Measures from experiments were used as a basis to validate estimations comparing results from models that include or exclude the presence of air. Outcomes generally showed a great correlation between simulation and experiments, with marginal differences in terms of accelerations, especially during the first phase of impact and considering the presence of air in the model.

https://www.mdpi.com/1996-1944/12/7/1162/pdf

Dealing with the Effect of Air in Fluid Structure Interaction by Coupled SPH-FEM Methods.

We consider a coupled problem of the deformation of a porous solid, flow of a compressible fluid and the electrical field in the mixture. The governing equations consist of balance of the linear momentum of solid and of fluid, continuity equations of the fluid and current density, and a generalized form of Darcy's law which includes electrokinetic coupling. The compressibility of the solid and the fluid are taken into account. We transform these equations to the corresponding finite element relations by employing the principle of virtual work and the Galerkin procedure. The nodal point variables in our general formulation are displacements of solid, fluid pore pressure, relative velocity of the fluid and electrical potential. Derivation of the FE equations is presented for small displacements and elastic solid, which can further be generalized to large displacements and inelastic behaviour of the solid skeleton.



According to this formulation we can include general boundary conditions for the solid, relative velocity of the fluid, fluid pressure, current density and electrical potential. The dynamic-type non-symmetric system of equations is solved through the Newmark procedure, while in the case of neglect of inertial terms we use the Euler method.



Numerical examples, solved by our general-purpose FE package PAK, are taken from biomechanics. The results are compared with those available in the literature, demonstrating the correctness and generality of the procedure presented. © 1998 John Wiley & Sons, Ltd.

Snezana Vulovic

Papers

Dealing with the Effect of Air in Fluid Structure Interaction by Coupled SPH-FEM Methods.

A finite element solution procedure for porous medium with fluid flow and electromechanical coupling