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Numerical investigations of pulsatile flow in stenosed artery

Bit A., Chattopadhyay H.

Acta of Bioengineering and Biomechanics

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2014

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Vol. 16, no. 4

33--44

EN

Purpose: Abnormalities in blood vessels by virtue of complex blood flow dynamics is being supported by non-Newtonian behavior of blood. Thus it becomes a focus of research to most of the researchers. Additionally, consideration of real life patient specific model of vessel as well as patient specific inlet flow boundary condition implementation was limited in literature. Thus a thorough implementation of these considerations was done here.Method: In this work, a numerical investigation of hemodynamic flow in stenosed artery has been carried out with realistic pulsating profile at the inlet. Flow has been considered to be laminar due to arresting condition of cardiovascular state of the subject. Two non-Newtonian rheological models namely, Power Law viscosity model and Quemada viscosity model have been used. Two different patient-specific pulsatile profiles are considered at the inlet of a long stenosed artery with varying degree of stenoses from 25% to 80%. Results: Transient form of Navier-Stokes equation is solved in an axi-symmetric domain to calculate the detailed flow structure of the flow field. From the simulation data, temporal and time averaged wall shear stress, oscillatory shear index and pressure drop are calculated. Conclusions: The results demonstrate that oscillatory shear index and wall shear stresses areextensively governed by the degree of stenoses. The position and movement of recirculation bubbles are found to vary with flow Reynolds number.

2

Influence of junction angle on hemodynamics in a bypass model

Vimmr J., Jonasova A.

Modelling and Optimization of Physical Systems

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2007

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z. 6

153--156

EN

The problem of steady laminar flow of an incompressible Newtonian fluid through an idealized 2-D bypass model with a stenosed coronary artery is solved using the finite volume approach of the MacCormack and Runge-Kutta schemes. The bypass model includes proximal and distal parts of the artery together with end-to-side graft. The changes of hemodynamics are investigated with three different junction angles (ɑ = 20°,45°,70°) between the graft and the artery. The velocity and wall shear stress distributions obtained using both numerical schemes for all three cases are analyzed and compared with each other.

3

Zastosowanie elektrycznego schematu zastępczego do analizy zmian przepływu krwi w nerce

Matulewicz W., Muc A., Retkowski M.

Przegląd Elektrotechniczny

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2006

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R. 82, nr 6

63-65

PL

Podano podstawę przedstawiania krwiobiegu w postaci przepływu prądu w zastępczym obwodzie elektrycznym. Zasady te zostały zastosowane do odwzorowania krwiobiegu nerki. Istotą badań symulacyjnych z zastosowaniem obwodu elektrycznego jest opracowanie sposobu identyfikacji przyczyn zmian przebiegu prądu, który odwzorowuje przebieg krwi. Jest to bardzo ważne zagadnienie w przypadku diagnostyki nerki po transplantacji umożliwiającej wykrycie zmian stanu krwiobiegu nerki.

EN

Basic principles of showing the blood circulation in the form of current flow in the equivalent circuit were described. These principles have been employed formodeling of the kidney blood circulation. The essence of simulation research with using the electric circuit is a method of the identification of reasons for changes in the current waveform, which the course of blood is copying. This problem is very important in the case of the kidney diagnostic after the transplantation.