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A numerical simulation of peristaltic motion in the ureter using fluid structure interactions
Bahman Vahidi1, Nasser Fatouraee
1Biomedical Engineering Faculty, Amirkabir University of Technology (Tehran Polytechnic), Tehran, Iran. vahidi.bahman@gmail.com
Summary
This study models ureter flow and stress using fluid-structure interactions (FSI). High shear stresses and backward flow occur at the beginning of peristalsis, suggesting a higher probability of reflux during initial wall motion.
Area of Science:
- Biomedical Engineering
- Fluid Dynamics
- Urology
Background:
- Ureter function involves complex fluid dynamics and structural interactions.
- Understanding ureter peristalsis is crucial for diagnosing and treating urinary tract conditions.
Purpose of the Study:
- To analyze ureter flow and stress distribution using a computational model.
- To investigate the impact of peristalsis on fluid dynamics and identify potential reflux mechanisms.
Main Methods:
- Developed an axisymmetric model incorporating fluid-structure interactions (FSI).
- Solved Navier-Stokes equations for fluid and a linear elastic model for ureter.
- Utilized the Newton-Raphson iterative method for finite element analysis.
Main Results:
- Identified high shear stresses near the throat of the contracted ureter wall.
- Observed maximum pressure gradients at the contracted wall throat, decreasing towards the bladder.
- Detected backward flow regions, particularly at the start of peristalsis, suggesting reflux potential.
Conclusions:
- Reflux is more probable during the initial phase of ureter peristaltic motion.
- The computational model provides insights into ureter biomechanics and flow patterns.
- Findings contribute to understanding ureter function and associated pathologies.
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