Computational investigation of wall shear stress-driven in-stent restenosis

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Swirlgraft versus conventional straight graft as vascular access: a full CFD-analysis

Two 3D models of an arterio-venous graft, a connection between an artery and a vein as vascular access for hemodialysis, were studied. One model of a conventional straight loop graft, the other of a graft with helical configuration (e.g. SwirlGraft (Veryan Medical, London, UK)). The statement that the helical design reduces Intimal Hyperplasia (IH) formation was studied by evaluating low wall shear stress and high oscillatory shear stress zones next to the helicity flow index. The IH-inducing zones were reduced but were not eliminated and the helicity of the flow was increased. The statement that the SwirlGraft avoids stenosis should however be considered with care in clinical practice

Finite volume and finite element schemes for the euler equations in cylindrical and spherical coordinates

A numerical scheme is presented for the solution of the compressible Euler equations over unstructured grids in cylindrical and spherical coordinates. The proposed scheme is based on a mixed finite volume / finite element approach. Numerical simulations are presented for the explosion problem in two spatial dimensions in cylindrical and spherical coordinates, and the numerical results are compared with the one-dimensional simulation for cylindrically and spherically symmetric explosions