Flow diverter stents simulation with CFD: porous media modelling

N. DAZEO; J. DOTTORI; G. BORONI; A. CLAUSSE; I. LARRABIDE

Tandil

Simposio; SIPAIM; 2016

Intracranial aneurysm treatment with flow diverters stent (FDs) is a minimally invasive approach for use inhuman patients. Because this treatment is strongly related to blood flow, flow simulation by CFD is an attrac-tive method to study FDs. Such flow simulations generally define geometries of aneurysms and stents in thecomputation by creating calculation meshes in the fluid space. For the other hand, generating a mesh in porousmedia (PM) sometimes represents a smaller computational load than generating realistic stent geometries withCFD, particularly for the small gaps between stent struts. For this reason, PMs become attractive to simulateFDs. To find the proper parameters, we investigated Darcy-Forchheimer model for porous media. The modeldescribes the relation between the pressure drop and flow velocity considering a viscous permeability (linearmodel?s term), and an inertial permeability (quadratic model?s term). Finally, two stage studies were performed.First, we verified flow model validity at different angles in known flow conditions. Second, model validation waschecked for a channel with no-slip boundary conditions. Results indicate that resistance calculated accordingto model has a difference of less than 3.5 % which is appropriate to characterize the FDs.