By analogy with laminar shear, du dy T V Bossiness in 1877 postulated that turbulent shear could also be related to the mean velocity gradient turb du dy, where is called the eddy viscosity and is much larger than If the logarithmic overlap law, Eq (6 28), is valid with w, show that u y ...

Differentiate the loglaw Eq 628 to find ...

By analogy with laminar shear, = du/dy. T. V. Bossiness in 1877 postulated that turbulent shear could

Question:

By analogy with laminar shear, τ = μ du/dy. T. V. Bossiness in 1877 postulated that turbulent shear could also be related to the mean-velocity gradient τturb = ε du/dy, where ε is called the eddy viscosity and is much larger than μ. If the logarithmic-overlap law, Eq. (6.28), is valid with τ ≈ τw, show that ε ≈ κρu*y.