5. A 1 cm , 4 m long diameter resistance heater rod is to be used to heat water at 15°C is to 65°C by passing it over the heater rod that maintained at 90°C. Water approaches the heater rod in normal direction at a mean velocity of 0.8 m/s. The rods are arranged in-line with longitudinal and transverse pitches of SL = 4 cm and ST = 3 cm. Determine the number of tube rows NL in the flow direction needed to achieve the indicated temperature rise. %3D %3D Water 15°C 0.8 m/s = 4 cm, D=1 cm T = 90°C S = 3 cm

5. A 1 cm , 4 m long diameter resistance heater rod is to be used to heat water at 15°C is to 65°C by passing it over the heater rod that maintained at 90°C. Water approaches the heater rod in normal direction at a mean velocity of 0.8 m/s. The rods are arranged in-line with longitudinal and transverse pitches of SL = 4 cm and ST = 3 cm. Determine the number of tube rows NL in the flow direction needed to achieve the indicated temperature rise. %3D %3D Water 15°C 0.8 m/s = 4 cm, D=1 cm T = 90°C S = 3 cm

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 5.65P

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