The GATE Grind

GATE 2021 ME (ME2) – Question 22

Fluid Mechanics · Viscous flow, boundary layer and elementary turbulent flow · 1 mark · Multiple choice

Which of the following is responsible for eddy viscosity (or turbulent viscosity) in a turbulent boundary layer on a flat plate?

  1. Nikuradse
  2. Reynolds
  3. Boussinesq
  4. Prandtl

Practise this question in The GATE Grind →

Show answer and explanation

Correct answer: (B) Reynolds

Explanation

Turbulent velocity fluctuations transport momentum, producing averaged stresses such as $-\rho\overline{u^{\prime}v^{\prime}}$. These are **Reynolds stresses (B)**.

Eddy-viscosity models express their effect using a viscosity-like coefficient and mean velocity gradient.