If the equation for the velocity profile is given by: v = 4y^2/3. Assuming v is in ft/s, what is the velocity gradient at the boundary and at y=0.25 ft and 0.5 ft from boundary?

Respuesta :

Answer:

At y = 0.25 ft velocity gradient will be 1.5866

At y = 0.5 ft velocity gradient will be 1.257

Explanation:

We have given velocity [tex]v=4y^{\frac{2}{3}}[/tex]

We have to find velocity gradient

Velocity gradient is nothing but rate of change of velocity

So velocity gradient [tex]=\frac{dv}{dy}=\frac{2}{3}y^{\frac{-1}{3}}[/tex]

(a) Now velocity gradient at y = 0.25 ft

[tex]=\frac{dv}{dy}_{y=0.25}=\frac{2}{3}0.25^{\frac{-1}{3}}=1.5866[/tex]

(b) Velocity gradient at y = 0.5 ft

[tex]=\frac{dv}{dy}_{y=0.5}=\frac{2}{3}0.5^{\frac{-1}{3}}=1.257[/tex]