Biomedical & Healthcare: Blood Flow in Clogged Artery

When plaque builds up inside an artery, the narrowing of the vessel changes the way blood flows and, critically, the pressure it must overcome to pass through. Understanding that pressure behavior is central to diagnosing and treating cardiovascular disease, and CFD offers a powerful, non-invasive way to study it. In this project, you'll use ANSYS Fluent to simulate blood flow through a clogged artery and investigate how a blockage drives the pressure changes along the vessel.

The model is a three-dimensional cylindrical vessel, 0.18 m long and 0.004 m in diameter, with a curved blockage at its center. The constriction is defined mathematically by a Gaussian function that describes how the vessel radius narrows along its length — here representing a 90% clogging severity with a defined slope through the blocked region — and is built in ANSYS DesignModeler by importing a set of coordinate points and revolving the resulting curve around the central axis. Blood is modeled as a fluid with a density of 1035 kg/m³ and a viscosity of 0.0043 Pa·s, entering at a mass flow rate of 0.013662 kg/s. The geometry is meshed in ANSYS Meshing with a structured grid of roughly 431,000 elements.

The case is solved with a pressure-based, steady-state solver under the assumption of laminar flow, with gravity neglected. Blood enters through a mass-flow inlet, the outlet is set as a pressure outlet at zero gauge pressure, and the vessel wall is treated as a stationary no-slip wall. From the results, you'll examine 2-D and 3-D contours of pressure, velocity, and pressure gradient, along with a plot of static pressure measured along the dimensionless length of the vessel. The results show clearly that the largest pressure drop occurs as the blood squeezes through the clogged region.

By the end of this project, you'll be able to build a parametric, function-defined biological geometry, set up a laminar internal-flow case in ANSYS Fluent, and interpret pressure and velocity fields to quantify how an arterial blockage affects blood flow.