Question

For turbulent now the friction factor is function of (Reynolds number —surface roughness -both the Reynolds number and the surface roughness) of the pipe.

Answer 1

Answer:

Both Reynolds and surface roughness

Explanation:

For turbulent flow friction factor is a function of both Reynolds and surface roughness of the pipe.But on the other hand for laminar flow friction factor is a function of only Reynolds number.

Friction factor for turbulent flow:

1.   For smooth pipe

$f=0.0032+\dfrac{0.221}{Re^{0.237}}$

$5\times 10^4$

2.   For rough pipe

$\dfrac{1}{\sqrt f}=2\ log_{10}\frac{R}{K}+1.74$

Where R/K is relative roughness

Friction factor for laminar flow:

$f=\dfrac{64}{Re}$