A thin-walled double-pipe, counter-flow heat exchanger is to be used to cool oil (cp = 0.525 Btu/lbm·°F) from 300°F to 105°F at a rate of 5 lbm/s by water (cp = 1.0 Btu/lbm·°F) that enters at 70°F at a rate of 3 lbm/s. The diameter of the tube is 5 in and its length is 200 ft. Determine the overall heat transfer coefficient of this heat exchanger using (a) the LMTD method and (b) the «-NTU method.

A thin-walled double-pipe, counter-flow heat exchanger is to be used to cool oil (cp = 0.525 Btu/lbm·°F) from 300°F to 105°F at a rate of 5 lbm/s by water (cp = 1.0 Btu/lbm·°F) that enters at 70°F at a rate of 3 lbm/s. The diameter of the tube is 5 in and its length is 200 ft. Determine the overall heat transfer coefficient of this heat exchanger using (a) the LMTD method and (b) the «-NTU method.

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 7.54P

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