A long counter-flow heat exchanger heats water from 15°C to 35°C by passing the water via the inner tube through an enclosure of hot air. The water is flowing through a 3.5-cm diameter tube at a rate of 0.3 kg/s. The air enters the enclosure at 80°C and exits at 30°C. 1536.7 W/m2K (a) Assuming the flow is fully developed, find out the convection coefficient of the water flow. (b) If the convection coefficient of air is 680 W/m².K, what is the length of the heat exchanger? 17.72 m Water Air

A long counter-flow heat exchanger heats water from 15°C to 35°C by passing the water via the inner tube through an enclosure of hot air. The water is flowing through a 3.5-cm diameter tube at a rate of 0.3 kg/s. The air enters the enclosure at 80°C and exits at 30°C. 1536.7 W/m2K (a) Assuming the flow is fully developed, find out the convection coefficient of the water flow. (b) If the convection coefficient of air is 680 W/m².K, what is the length of the heat exchanger? 17.72 m Water Air

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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