In general, blood flow becomes turbulent at Reynolds numbers exceeding which value?

In general, blood flow becomes turbulent at Reynolds numbers exceeding which value?

• A. 2500
• B. 1000
• C. 2000
• D. 1500

Answer: (C)

This question tests understanding of when blood flow shifts from smooth (laminar) to chaotic (turbulent) motion, driven by the Reynolds number. Reynolds number compares inertial forces to viscous forces in the flow and is given by Re = rho v D / mu. In a healthy, straight, smooth vessel, laminar flow generally persists at lower Re, and turbulence tends to arise when Re crosses about 2000. So the general threshold where turbulence becomes more likely is around 2000. Keep in mind the exact point can vary with pulsatility, vessel geometry, branching, and any obstructions, but 2000 is the standard cutoff used here.

This question tests understanding of when blood flow shifts from smooth (laminar) to chaotic (turbulent) motion, driven by the Reynolds number. Reynolds number compares inertial forces to viscous forces in the flow and is given by Re = rho v D / mu. In a healthy, straight, smooth vessel, laminar flow generally persists at lower Re, and turbulence tends to arise when Re crosses about 2000. So the general threshold where turbulence becomes more likely is around 2000. Keep in mind the exact point can vary with pulsatility, vessel geometry, branching, and any obstructions, but 2000 is the standard cutoff used here.