A 12-m-long countercurrent-flow heat exchanger is being used to heat a liquid food from 20 to 90°C. The heating medium is oil, which enters the heat exchanger at 160°C and exits at 110°C. The specific heat of the liquid food is 4.0 kJ/(kg-°C). The overall heat- transfer coefficient based on the inside area is 1000 W/(m²-°C). The inner diameter of the inside pipe is 6 cm. (a) Estimate the flow rate of the liquid food. (b) Determine the flow rate of the liquid food if the heat exchanger is operated in a concurrent-flow mode for the same conditions of temperatures at the inlet and exit from the heat exchanger.

A 12-m-long countercurrent-flow heat exchanger is being used to heat a liquid food from 20 to 90°C. The heating medium is oil, which enters the heat exchanger at 160°C and exits at 110°C. The specific heat of the liquid food is 4.0 kJ/(kg-°C). The overall heat- transfer coefficient based on the inside area is 1000 W/(m²-°C). The inner diameter of the inside pipe is 6 cm. (a) Estimate the flow rate of the liquid food. (b) Determine the flow rate of the liquid food if the heat exchanger is operated in a concurrent-flow mode for the same conditions of temperatures at the inlet and exit from the heat exchanger.

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 7.49P

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