Convection H.T. Q3: In an industrial facility, air is to be preheated before entering a furnace by geothermal water at 120°C flowing through the tubes of a tube bank located in a duct. Air enters the duct at 20°C and 1 atm with a mean velocity of 4.5 m/s, and flows over the tubes in normal direction. The outer diameter of the tubes is 1.5 cm, and the tubes are arranged in-line with longitudinal and transverse pitches of SL = Sr = 5 cm. There are 6 rows in the flow direction with 10 tubes in each row. Determine the rate of heat transfer per unit length of the tubes, and the pressure drop across the tube bank. For this square in-line tube bank, if the friction coefficient is 0.16. Also, the correction factor 1 for the square arrangements. Properties: (p = 1.06 kg/m', k =0.02808 W/m °C, u = 2.008x10-5 kg/m.s, Pr = 0.7202 and Cp= 1007 J/kg.K). Take C, = 0.286, C2 = 0.95 and m = 0.608. Ans. q = 23.12 kW, AP = 21 Pa]

Convection H.T. Q3: In an industrial facility, air is to be preheated before entering a furnace by geothermal water at 120°C flowing through the tubes of a tube bank located in a duct. Air enters the duct at 20°C and 1 atm with a mean velocity of 4.5 m/s, and flows over the tubes in normal direction. The outer diameter of the tubes is 1.5 cm, and the tubes are arranged in-line with longitudinal and transverse pitches of SL = Sr = 5 cm. There are 6 rows in the flow direction with 10 tubes in each row. Determine the rate of heat transfer per unit length of the tubes, and the pressure drop across the tube bank. For this square in-line tube bank, if the friction coefficient is 0.16. Also, the correction factor 1 for the square arrangements. Properties: (p = 1.06 kg/m', k =0.02808 W/m °C, u = 2.008x10-5 kg/m.s, Pr = 0.7202 and Cp= 1007 J/kg.K). Take C, = 0.286, C2 = 0.95 and m = 0.608. Ans. q = 23.12 kW, AP = 21 Pa]

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.

Chapter7: Forced Convection Inside Tubes And Ducts

Section: Chapter Questions

Problem 7.31P

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