Question

Identify Leonard stresses from the following.

(a) \(\rho\overline{\overline{u_i}\overline{u_j}}\, – \rho\overline{u_i}\overline{u_j}\)

(b) \(\rho\overline{\overline{u_i}\overline{u_j}}\)

(c) \(\rho\overline{u_i}\overline{u_j}\)

(d) \(\rho\overline{\overline{u_i}\overline{u_j}}\, – \rho\overline{u_i}\overline{u_j}\)

This question was addressed to me at a job interview.

I'd like to ask this question from Turbulence Modelling topic in portion Turbulence Modelling of Computational Fluid Dynamics

Answer 1

Right answer is (a) \(\rho\overline{\overline{u_i}\overline{u_j}}\, – \rho\overline{u_i}\overline{u_j}\)

To elaborate: The term \(\rho\overline{\overline{u_i}\overline{u_j}}\, – \rho\overline{u_i}\overline{u_j}\) is named Leonard stresses. It is named after an American Scientist A. Leonard who first identified an approximate method to compute them from the filtered flow.