Spectral Decomposition and Sound Source Localization of Highly Disturbed Flow through a Severe Arterial Stenosis

Area of Science:

• Biomedical Engineering
• Fluid Dynamics
• Medical Diagnostics

Background:

• Early atherosclerosis detection is crucial for reducing mortality and treatment costs.
• Noninvasive diagnostic techniques are needed to assess arterial stenosis.
• Turbulent flow in stenotic arteries generates mechano-acoustic signals.

Purpose of the Study:

• To investigate turbulent flow dynamics in arterial stenosis.
• To identify high-energy mechano-acoustic sources for noninvasive detection.
• To correlate flow characteristics with acoustic signal generation.

Main Methods:

• Computational fluid dynamics (CFD) simulations of arterial stenosis.
• Signal processing techniques for analyzing flow data.
• Proper orthogonal decomposition (POD) and spectral analysis of turbulent flow.

Main Results:

• Turbulent pressure fluctuations identified within and post-stenosis.
• Maximum flow excitation located two diameters downstream of stenosis.
• Higher pressure fluctuation concentration near the wall within the stenosis.
• Break frequencies correlated with eddy generation, ranging from 80 to 220 Hz.

Conclusions:

• CFD and signal processing can identify acoustic sources in stenotic arteries.
• Flow characteristics provide insights into potential noninvasive atherosclerosis detection methods.
• Understanding turbulent flow is key to developing new diagnostic tools.