Chapter 8, Problem 8.121P

Air flowing through a tube of $\text{75}-\text{mm}$ diameter passes over a 150-nuniong roughened Section that is constructed from naphthalene having the properties $M=128.16\text{kg}/\text{kmol}$ and $p_{sat}\left(300\text{K}\right)=1.31\times {10}^{-4}$ bar. The air is at 1 atmand $\text{3}00\text{ K}$ , and the Reynolds number is ${\mathrm{R}}_{eD}=35,000$ . In an experiment for which flow was maintained for 3 h. mass loss due to sublimation from the roughened surface was determined to be $0.0\text{1 kg}$ . What is the associated convection mass transfer coefficient? What would be the corresponding convection heat transfer coefficient? Contrast these results with those predicted by conventional smooth tube correlations.