Question

When the Reynolds number increases, the difference between the large and small scales ____________

(a) increases

(b) decreases

(c) remains constant

(d) cannot be defined

The question was posed to me by my college professor while I was bunking the class.

Question is taken from Turbulence Modelling in division Turbulence Modelling of Computational Fluid Dynamics

Answer 1

The correct answer is:

(a) increases

As the Reynolds number increases, the difference between the large and small scales of turbulence increases. This is because higher Reynolds numbers correspond to more intense turbulence, with larger eddies (large scales) and smaller turbulent structures (small scales) becoming more distinct.