A heat exchanger is to be designed to heat 4000 cfm (1.9 m3/s) of air from 50 F (10 C) to 110 F (43 C) using hot water at 180 F (82 C) in a cross-flow arrangement with fluids unmixed. The flow rate of the hot water is 25 gpm (1.6 L/s). Assume the overall heat-transfer coefficient based on the air side is 10 Btu/(hr-ft-F) (57 W/(m2-C)], and determine the air-side surface area using (a) the LMTD method and (b) the NTU method.

A heat exchanger is to be designed to heat 4000 cfm (1.9 m3/s) of air from 50 F (10 C) to 110 F (43 C) using hot water at 180 F (82 C) in a cross-flow arrangement with fluids unmixed. The flow rate of the hot water is 25 gpm (1.6 L/s). Assume the overall heat-transfer coefficient based on the air side is 10 Btu/(hr-ft-F) (57 W/(m2-C)], and determine the air-side surface area 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.

Chapter10: Heat Exchangers

Section: Chapter Questions

Problem 10.20P

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