Saturated steam at 1 atm is condensed on the external surface of a copper tube with an outside diameter 16 mm and tube wall of thickness 0.5 mm. The tube is cooled internally by water with a mass flow rate of 0.06 kg/s, which in turn is raised in temperature from 15 °C to 60 °C as it flows through the tube. Take the heat-transfer coefficient at the condensing side as 10.0 kW/m² K and the isobaric specific heat-capacity of water as 4180 J/kg K. i) Calculate the heat transfer rate to the cooling water. ii) Calculate the length of the tube. iii) Comment on how to enhance heat transfer in this case.

Saturated steam at 1 atm is condensed on the external surface of a copper tube with an outside diameter 16 mm and tube wall of thickness 0.5 mm. The tube is cooled internally by water with a mass flow rate of 0.06 kg/s, which in turn is raised in temperature from 15 °C to 60 °C as it flows through the tube. Take the heat-transfer coefficient at the condensing side as 10.0 kW/m² K and the isobaric specific heat-capacity of water as 4180 J/kg K. i) Calculate the heat transfer rate to the cooling water. ii) Calculate the length of the tube. iii) Comment on how to enhance heat transfer in this case.

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 7.4P

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