A hot fluid (60° C) flows inside an copper tube with 1.7 cm OD and 1.5 cm ID. The inside of the pipe has a heat transfer coefficient of 130 W/m2-K. The tube is exposed to a room with air and surrounding walls of 23° C. The heat transfer coefficent between the outside of the walls and the room air is 15 W/m2 K. Draw an equivalent circuit diagram of the heat transfer, and quantify the resistance to heat flow by each of the two convective processes, conduction in the tube, and radiation between the outside of the tube and the room walls. Are any of the resistances negligible to the overall heat transfer, and if so, which ones?

A hot fluid (60° C) flows inside an copper tube with 1.7 cm OD and 1.5 cm ID. The inside of the pipe has a heat transfer coefficient of 130 W/m2-K. The tube is exposed to a room with air and surrounding walls of 23° C. The heat transfer coefficent between the outside of the walls and the room air is 15 W/m2 K. Draw an equivalent circuit diagram of the heat transfer, and quantify the resistance to heat flow by each of the two convective processes, conduction in the tube, and radiation between the outside of the tube and the room walls. Are any of the resistances negligible to the overall heat transfer, and if so, which ones?

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.

Chapter2: Steady Heat Conduction

Section: Chapter Questions

Problem 2.21P

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