Problem #$1$:

Given: Water flows inside a $2-$inch pipe at a velocity of $0\mathrm{.}25\frac{m}{s}.$ The temperature of the water is $96C.$ The exterior of the pipe is exposed to ambient condition $23C$ air.

Assume: The pipe is Sch $40$ black steel. No fouling is considered. $h_0=7\mathrm{.}9\frac{W}{m^2}K$

Find: The overall heat transfer coefficient, $U$ in units of $\frac{W}{K},$ for a $1$ m length