Which of the following Reynolds numbers do(es) NOT represent creeping flow?

Question

A single degree of freedom system is undergoing free oscillation. The natural frequency and damping ratio of the system are $1$ rad/s and $0.01$ respectively. The reduction in peak amplitude over three cycles is __________% (rounded off to one decimal place).

Answer 1

Creeping flow is the name given to very slow, highly viscous flow where the Reynolds number stays well under 1, so inertia forces barely matter compared with viscous forces.

0.01: This is much smaller than 1, so it sits comfortably in the creeping flow range.
0.001: Also much smaller than 1, again a creeping flow value.
$5 \times 10^5$: This is an extremely large Reynolds number, typical of fully turbulent flow, far outside the creeping flow range.
2300: This is the usual number quoted for transition from laminar to turbulent pipe flow, which is nowhere near the creeping flow limit.

So options C and D are the Reynolds numbers that do not represent creeping flow.

Answer 2

Creeping flow is the name given to very slow, highly viscous flow where the Reynolds number stays well under 1, so inertia forces barely matter compared with viscous forces.

0.01: This is much smaller than 1, so it sits comfortably in the creeping flow range.
0.001: Also much smaller than 1, again a creeping flow value.
$5 \times 10^5$: This is an extremely large Reynolds number, typical of fully turbulent flow, far outside the creeping flow range.
2300: This is the usual number quoted for transition from laminar to turbulent pipe flow, which is nowhere near the creeping flow limit.

So options C and D are the Reynolds numbers that do not represent creeping flow.

Which of the following Reynolds numbers do(es) NOT represent creeping flow?

Show Hint

The Correct Option is C, D

Solution and Explanation

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