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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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Physiologic blood flow is turbulent
Khalid M Saqr1, Simon Tupin2, Sherif Rashad3,4
1Biomedical Flow Dynamics Laboratory (Ohta-Lab), Institute of Fluid Science, Tohoku University, Sendai, Miyagi, 980-8577, Japan. k.saqr@tohoku.ac.jp.
Scientific Reports
|September 24, 2020
Summary
Physiologic blood flow exhibits turbulence, challenging the laminar flow assumption. This finding, supported by chaos theory and fluid dynamics, suggests a new understanding of vascular hemodynamics and related diseases.
Area of Science:
- Fluid Dynamics
- Biophysics
- Cardiovascular Science
Background:
- Current vascular hemodynamics models assume laminar blood flow.
- Turbulence is linked to diseases like atherosclerosis, stenosis, and aneurysms.
- Previous studies detected turbulence in intracranial aneurysms at low Reynolds numbers.
Purpose of the Study:
- To investigate the origins of the assumption of laminar physiologic blood flow.
- To test the hypothesis that blood flow dynamics in arteries inherently cause turbulence.
- To explore the existence of turbulence in physiologic blood flow.
Main Methods:
- Applied chaos theory, hydrodynamic stability theory, and fluid dynamics.
- Utilized Womersley's exact solution of the Navier-Stokes equation.
- Analyzed flow waveforms from the HaeMod database and Doppler ultrasound measurements.
Main Results:
- Physiologic blood flow exhibits three key turbulence characteristics: sensitivity to initial conditions, global hydrodynamic instability, and non-Kolmogorov kinetic energy cascade.
- Evidence supports turbulence in blood flow described by the Navier-Stokes equation and observed in vivo.
- Findings challenge the traditional view of laminar blood flow.
Conclusions:
- Physiologic blood flow is inherently turbulent, not laminar.
- Proposes a novel modification to vascular hemodynamics theory.
- Calls for rethinking hemodynamic-biologic links in health and disease.
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