Chapter 13, Problem 13.37P

Water flowing through a large number of long, circular, thin-walled tubes is heated by means of ho parallel plates above and below the tube array. The space between the plates is evacuated, and the plate and tube surfaces may be approximated as blackbodies.

(a) Neglecting axial variations, determine the tube surface temperature, T_s, if water flows through each tube at a mass rate of $\stackrel{\dot{}}{m}=0.20\text{kg/s}$ and a mean temperature of $T_m=300\text{K}$ .
(b) Compute and plot the surface temperature as a function of flow rate for $0.05\le \stackrel{\dot{}}{m}\le 0.25\text{kg/s}$ .