Question

There will be a transition from laminar flow to turbulent flow when______

(a) Reynolds number increases

(b) Reynolds number decreases

(c) Reynolds number is the same

(d) Froude’s number increases

This question was addressed to me during an online exam.

This intriguing question originated from Drag on a Sphere topic in chapter Boundary Layer Flow & Forces on Sub-merged Bodies of Fluid Mechanics

Answer 1

Right answer is (a) Reynolds number increases

Best explanation: There will be a transition from laminar flow to turbulent flow with the increase in the Reynolds number. Reynolds number below 2000 is laminar flow and Reynolds number above 2000 is for turbulent flow.