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Updated: Sep 10, 2025
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In Vitro Model of Physiological and Pathological Blood Flow with Application to Investigations of Vascular Cell Remodeling
Published on: November 3, 2015
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Pulsatile flow in a thin-walled viscoelastic tube
Oleksander Krul1, Prosenjit Bagchi1
1Mechanical and Aerospace Engineering Department, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, USA.
Journal of Fluid Mechanics
|August 26, 2025
Summary
This study explores fluid flow in flexible, viscoelastic tubes. We found that wall viscosity and oscillation frequency significantly impact flow dynamics, causing unique elastic surges and squeezing effects.
Area of Science:
- Fluid Dynamics
- Biomedical Engineering
- Materials Science
Background:
- Biological and engineering systems often feature low inertia, pulsatile flows in distensible, viscoelastic vessels.
- Existing research frequently overlooks large deformations, focusing instead on inertial flows in minimally deformed vessels.
Purpose of the Study:
- To investigate the dynamics of a viscoelastic tube undergoing large deformations with low Reynolds number, oscillatory flow.
- To analyze the influence of wall viscosity and oscillation frequency on tube deformation, flow rate, phase shifts, and hysteresis.
Main Methods:
- Utilized a fully-coupled fluid/structure interaction computational model.
- Examined the effects of varying solid viscosity and oscillation frequency on flow physics and tube behavior.
Main Results:
- Observed elastic flow surge during inflation and squeezing during deflation.
- Increasing oscillation frequency enhanced flow rate and reduced distention; increasing solid viscosity decreased both.
- Deformation and flow rate are most sensitive within intermediate ranges of solid viscosity and oscillation frequency.
Conclusions:
- Tube dynamics exhibit complex phase shifts and hysteresis, with flow rate potentially leading or lagging pressure.
- Hysteresis direction is predictable by flow rate phase shifts and can be clockwise, counterclockwise, or mixed.
- High solid viscosity induces global tube motion, unlike in purely elastic tubes.
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