A tube bank consists of 300 tubes at a distance of 6 cm between the centerlines of any two adjacent tubes. Air approaches the tube bank in the normal direction at 20°C and 1 atm with a mean velocity of 6.3 m/s. There are 20 rows in the flow direction with 15 tubes in each row with an average surface temperature of 140°C. For an outer tube diameter of 2 cm, determine the average heat transfer coefficient. Assume the air properties at mean temperature of 70°C and 1 atm. The air properties at the assumed mean temperature of 70°C and 1 atm are k = 0.02881 W/m·K, ρ = 1.028 kg/m3, cp = 1.007 kJ/kg·K, Pr = 0.7177, μ = 2.052 × 10−5 kg/m·s, Prs = Pr@Ts = 140°C = 0.7041. The average heat transfer coefficient of the tube bank is W/m2·°C.

A tube bank consists of 300 tubes at a distance of 6 cm between the centerlines of any two adjacent tubes. Air approaches the tube bank in the normal direction at 20°C and 1 atm with a mean velocity of 6.3 m/s. There are 20 rows in the flow direction with 15 tubes in each row with an average surface temperature of 140°C. For an outer tube diameter of 2 cm, determine the average heat transfer coefficient. Assume the air properties at mean temperature of 70°C and 1 atm. The air properties at the assumed mean temperature of 70°C and 1 atm are k = 0.02881 W/m·K, ρ = 1.028 kg/m3, cp = 1.007 kJ/kg·K, Pr = 0.7177, μ = 2.052 × 10−5 kg/m·s, Prs = Pr@Ts = 140°C = 0.7041. The average heat transfer coefficient of the tube bank is W/m2·°C.

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter5: Analysis Of Convection Heat Transfer

Section: Chapter Questions

Problem 5.7P: 5.7 The average Reynolds number for air passing in turbulent flow over a 2-m-long, flat plate is ....

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