Question

What characterizes a turbulent flow compared to a laminar flow?

• A. Lower Reynolds number
• B. More chaotic energy distribution
• C. More predictable velocity profiles
• D. Lower viscosity

Hint:

Laminar vs. Turbulent Flow. Laminar: Smooth, ordered, low Re, predictable profile. Turbulent: Chaotic, eddies, mixing, high Re, flatter average profile, random fluctuations.

Answer 1

The Correct Option is B

- Laminar flow is characterized by smooth, orderly fluid motion in parallel layers or streamlines, occurring typically at low Reynolds numbers.
Velocity profiles are predictable (e.
g.
, parabolic for pipe flow).
- Turbulent flow is characterized by chaotic, irregular, and random fluid motion with eddies and significant mixing between fluid layers.
It occurs typically at high Reynolds numbers.
This chaotic motion leads to a more uniform average velocity profile (compared to laminar) but instantaneous velocities fluctuate randomly.
Energy is distributed across a wide range of eddy sizes, representing a chaotic energy distribution.
Comparing turbulent to laminar:
(1) Turbulent flow has a *higher* Reynolds number.
Incorrect.

(2) Turbulent flow involves eddies and random fluctuations, indicating a more chaotic distribution of kinetic energy within the flow.
Correct.

(3) Laminar flow profiles are generally more predictable than turbulent flow profiles (which are often described statistically).
Incorrect.

(4) Viscosity is a fluid property, not a characteristic determined by whether the flow is laminar or turbulent (though lower viscosity promotes turbulence).
Incorrect.