Question

The Nusselt number is related to Reynolds number in laminar and turbulent flows over a flat plate respectively are

• A. $R{e}^{0.5}andR{e}^{0.67}$
• B. $R{e}^{0.5}andR{e}^{0.33}$
• C. $R{e}^{0.5}andR{e}^{0.8}$
• D. $R{e}^{-0.5}andR{e}^{-0.8}$

Answer 1

The correct option is C $R{e}^{0.5}andR{e}^{0.8}$

For laminar flow over a flat plate

$N{u}_x=0.332R{e}_x^{0.5}.P{r}^{1/3}\to forlaminarflow$

$N{u}_x\propto R{e}_x^{0.5}$

For turbulent flow over a flat plate

$N{u}_x=\mathrm{0.029.}R{e}_x^{0.8}P{r}^{0.4}$

$N{u}_x\propto R_e^{0.8}\to forturbulentflow$