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Hemodynamics in aneurysm.

B V Kumar·K B Naidu
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Abstract

A numerical simulation of hemodynamics in blood vessels with 0-75% dilation is made. A transient UVP finite element method (FEM) and a stable time integration scheme, based on a predictor-corrector strategy, with constant error monitoring are employed in the flow analysis. The pulsatile flow is analyzed without any assumptions in nonlinear terms and is characterized by thoroughly analyzing the flow, pressure, and stress fields. The central axis velocity, central axis and wall pressures, pressure gradient history, and wall shear stress are influenced by the presence of aneurysm. Time-dependent recirculation regions which are sensitive to the degree of dilation of the vessel are seen in the concavity of the dilation. The transverse velocities and their variations with time are found to be too significant to be neglected. The effects of nonlinear convective terms and the nonlinear geometry of the vessel are clearly depicted through the transverse velocity and pressure profiles.

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AlgorithmsAneurysmBlood Flow VelocityBlood PressureBlood VesselsComputer SimulationDilatation, PathologicHemodynamicsHemorheologyHumansModels, CardiovascularNonlinear DynamicsPulsatile FlowRegional Blood FlowStress, MechanicalJournal Article

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BibTeXRIS

B V Kumar, K B Naidu. 1996. Hemodynamics in aneurysm.. https://doi.org/10.1006/cbmr.1996.0011

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