Question

For a 2-D flow, what is the mixing length of the mixing layer turbulence model?

(a) 0.1 of layer width

(b) 0.09 of layer width

(c) 0.08 of layer width

(d) 0.07 of layer width

I had been asked this question during an online exam.

This intriguing question comes from Mixing Length Turbulence Model topic in section Turbulence Modelling of Computational Fluid Dynamics

Answer 1

Right option is (d) 0.07 of layer width

The explanation: Mixing length varies for different turbulent flows. For free turbulent flow of the mixing layer type, the mixing length is 0.07 times of the layer width. Mixing layer turbulent flow occurs due to the interaction of two flows with various velocities.