Question: Repeat Problem for a heat transfer coefficient of 40 W/m2K.
Problem: Combustion gases passing through a 3-cm-internaldiameter circular tube are used to vaporize waste water at atmospheric pressure. Hot gases enter the tube at 115 kPa and 250°C at a mean velocity of 5 m/s, and leave at 150°C. If the average heat transfer coefficient is 120 W/m2K and the inner surface temperature of the tube is 110°C, determine
(a) the tube length and
(b) the rate of evaporation of water.