How would you formulate this problem to obtain a more meaningful result which desired to cool a gas has [Cp 0.35 Btu/(Ib)(°F)] from 190 to 95°F, using cooling water at 83°F. Water costs $0.30/1100 ft', and the annual fixed charges for the exchanger are $0.60/ft of inside surface, with a diameter of 0.0775 ft. The heat transfer coefficient is U= 8 Btu/(h)(ft)(F) for a gas rate of 2900 Ib/hr. Plot the annual cost of cooling water and fixed charges for the exchanger as a function of the outlet water temperature. What is the minimum total cost?

How would you formulate this problem to obtain a more meaningful result which desired to cool a gas has [Cp 0.35 Btu/(Ib)(°F)] from 190 to 95°F, using cooling water at 83°F. Water costs $0.30/1100 ft', and the annual fixed charges for the exchanger are $0.60/ft of inside surface, with a diameter of 0.0775 ft. The heat transfer coefficient is U= 8 Btu/(h)(ft)(F) for a gas rate of 2900 Ib/hr. Plot the annual cost of cooling water and fixed charges for the exchanger as a function of the outlet water temperature. What is the minimum total cost?

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 7.27P

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