A double-pipe heat exchanger is constructed of a copper (k = 380 W/m-°C) inner tube of internal diameter D; = 1.2 cm and external diameter D. = 1.6 cm and an outer tube of diameter 3.0 cm. The convection heat transfer coefficient is reported to be h; = 700 W/m2°C on the inner surface of the tube and h, = 1400 W/m2°C on its outer surface. For a fouling factor Rf; = 0.0005 m2 C/W on the tube side and Rio = 0.0002 m2°CW on the shell side, determine the thermal resistance of the heat exchanger per unit length. m2-KAW

A double-pipe heat exchanger is constructed of a copper (k = 380 W/m-°C) inner tube of internal diameter D; = 1.2 cm and external diameter D. = 1.6 cm and an outer tube of diameter 3.0 cm. The convection heat transfer coefficient is reported to be h; = 700 W/m2°C on the inner surface of the tube and h, = 1400 W/m2°C on its outer surface. For a fouling factor Rf; = 0.0005 m2 C/W on the tube side and Rio = 0.0002 m2°CW on the shell side, determine the thermal resistance of the heat exchanger per unit length. m2-KAW

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 7.46P

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