Question

The dynamic turbulent viscosity is ___________

(a) equal to the product of turbulent length and time scales

(b) proportional to the product of turbulent length and time scales

(c) proportional to the product of kinematic turbulent viscosity and density of the fluid

(d) equal to the product of kinematic turbulent viscosity and density of the fluid

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This is a very interesting question from Turbulent Viscosity topic in portion Turbulence Modelling of Computational Fluid Dynamics

Answer 1

The correct choice is (d) equal to the product of kinematic turbulent viscosity and density of the fluid

Explanation: Dynamic viscosity is the product of kinematic viscosity and density in general. This applies to the turbulent viscosities also.

μt=ρνt

Where,

νt →  Kinematic turbulent viscosity.

μt →  Dynamic turbulent viscosity.

ρ →  Density.