A staggered tube bank consisting of 6 rows with 10 tubes per row carries warm oil that maintains the tubes’ temperature at 80°C. Atmospheric nitrogen at 10°C approaches the tube bank at a velocity of 9 m/s. The diameter of the tubes is 1.85 cm, and the longitudinal and transverse tube pitches are 4 cm and 3.2 cm, respectively. What is the total rate of heat transfer to the steam? Determine the average heat transfer coefficient for the tube bank and the rate of heat transfer from the tube bank per meter of tube length. Neglect the change in air temperature across the tube bank.
(a) h̅ =
(b) q’ =