A shell-and-tube exchanger with 1-in. BWG 14 tubes will be used to cool a heavy oil from 120 to 50C, using cooling water at 25C. The oil properties are: 

(a) To help decide which fluid to put in the tubes, compare the oil-film coefficient for flow in the tubes at 30 cm/s with the coefficient outside the tubes at the same velocity. Assume G_b = G_c for flow on the shell side. 

(b) How is the comparison in part, (a) affected by the velocity chosen?