Overview

This study uses ANSYS Fluent software to simulate blood flow through an occluded artery via computational fluid dynamics (CFD) analysis.

The model features a bifurcated blood vessel with stenosis (narrowing) at its center. Blood properties are defined with a density of 1060 kg/m³ and dynamic viscosity of 0.35 kg/m·s. The stenotic region is mathematically defined using a curved function.

The primary objective is to analyze blood flow behavior through the narrowed section. Blood enters through two inlet branches at a combined mass flow rate of 0.002385 kg/s, while vessel walls are treated as rigid boundaries.

The model geometry was created using ANSYS Design Modeler and discretized with ANSYS Meshing, employing a structured mesh containing 85,222 elements.

Methodology

The vessel stenosis geometry was generated using a parametric curve function defined by the equation: y = 0.0002475cos(πx/0.001), which describes the coordinate points forming the narrowed profile.

As an illustration, a 30% stenosis indicates that the constricted diameter is 70% of the normal vessel diameter.

To evaluate fluid behavior under varying conditions, the stenosis severity was systematically varied across seven cases: 30%, 40%, 50%, 60%, 70%, 80%, and 90% occlusion.

Key Findings

Post-processing revealed 2D distributions of pressure and velocity, along with pathline and vector visualizations. Velocity contours demonstrate peak values precisely at the stenotic throat, where the flow cross-sectional area reaches its minimum.

Pressure distributions show a decline in fluid pressure downstream of the stenosis, with values dropping below the inlet branch pressures.

Graphical analysis of pressure, velocity, and pressure differential versus stenosis severity reveals that increasing occlusion percentage correlates with greater pressure losses and elevated blood velocities through the constricted zone, directly attributable to the enhanced flow obstruction.