Question:-
In a turbulent flow, ‘l’ is the prandtl’s mixing length and u/y is the gradient of the average velocity in the direction normal to flow. The final expression for the turbulent viscosity vt is given by
Option (A)
vt = l{`u/y}
Option (B)
vt = l1(`u/y)
Option(C)
vt = l2(`u/y)
Option(D)
vt = (`u/y)
Correct Option:
(C)
Question Solution:
By parndtl’s mixing length theory Shear stress t = r.l2 (d`u/dy)2
And t = h(d`u/dy) \ h = rl2(d`u/dy)
vt = (h/r) = l2 (d`u/dy)
question-answer-faq-5929