Solution Manual Heat And Mass Transfer Cengel 5th Edition Chapter 3 -

$\dot{Q}=\frac{T_{s}-T_{\infty}}{\frac{1}{2\pi kL}ln(\frac{r_{o}+t}{r_{o}})}$

Assuming $h=10W/m^{2}K$,

$\dot{Q}=h \pi D L(T_{s}-T_{\infty})$

$Re_{D}=\frac{\rho V D}{\mu}=\frac{999.1 \times 3.5 \times 2}{1.138 \times 10^{-3}}=6.14 \times 10^{6}$