Blood Flow in Clogged Artery

Description: When plaque accumulates inside an artery, the resulting narrowing alters blood flow behavior and, importantly, raises the pressure the blood must overcome to pass through the constricted region. This pressure response is a key diagnostic indicator in cardiovascular disease, and CFD provides a non-invasive way to study it in detail. This project uses ANSYS Fluent to simulate blood flow through a clogged artery and examine how the blockage drives pressure changes along the vessel.

Methodology: The geometry is a three-dimensional cylindrical vessel 0.18 m long and 0.004 m in diameter, featuring a curved constriction at its center. The narrowing is defined through a Gaussian function describing how the vessel radius contracts along its length, representing a 90% occlusion with a specified slope through the blocked segment; the geometry is built in ANSYS DesignModeler by importing coordinate points and revolving the resulting profile around the central axis. Blood is modeled 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, and the domain is meshed in ANSYS Meshing using a structured grid of roughly 431,000 elements. The simulation uses a pressure-based, steady-state solver with laminar flow assumptions and gravity neglected; a mass-flow inlet, a zero-gauge-pressure outlet, and a stationary no-slip wall complete the boundary conditions.

Analysis: The results are examined through 2-D and 3-D contours of pressure, velocity, and pressure gradient, alongside a plot of static pressure along the dimensionless vessel length. The data show that the most significant pressure drop occurs precisely where the blood is forced through the clogged region, confirming the direct link between occlusion severity and elevated flow resistance. Working through this project builds skill in constructing parametric, function-defined biological geometries, setting up laminar internal-flow cases in ANSYS Fluent, and interpreting pressure and velocity fields to quantify how an arterial blockage affects blood flow.