Shape optimization of an artificial bypass graft us ing genetic algorithms

Shape optimization has been applied in medical engi neering. It is our goal to establish an optimizatio n framework suited to perform shape optimization of complex geo metries in compute-intensive applications. In medic al practice, bypass grafts provide a way to restore bl ood flow in critically stenosed arteries, and, toge ther with stenting, constitute the most typical treatment in such cases. In this work, the numerical analysis of the blood f low phenomena uses the finite element method approach applied to a geometrical model of the artery and bypass. Bl ood flow is described by the incompressible Navier- Stokes equations and the simulation is carried out under s teady flow conditions. The optimization of the bypa ss geometry of an idealized artificial graft is searched aiming to minimize the shear rate integral. The shapes ar e described either using elliptical or sinusoidal functions. An evolutionary genetic algorithm is considered in or der to calculate the optimal shape for the graft geometry. Numerical results show the benefits of numerical shape optim ization in achieving design improvements.

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