Heat is generated in a 1.4 m long and 0.2 cm diameter electrical resistance wire placed in the middle of a room kept at 20 ° C. Under continuous conditions, the surface temperature of the wire was measured as 180 ° C, the voltage drop on the wire as 110 V and the electric current as 3 A. Find the heat transfer coefficient for the heat transfer between the surface of the wire shown in the figure and the room air, regardless of radiative heat transfer.

Heat is generated in a 1.4 m long and 0.2 cm diameter electrical resistance wire placed in the middle of a room kept at 20 ° C. Under continuous conditions, the surface temperature of the wire was measured as 180 ° C, the voltage drop on the wire as 110 V and the electric current as 3 A. Find the heat transfer coefficient for the heat transfer between the surface of the wire shown in the figure and the room air, regardless of radiative heat transfer.

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.

Chapter8: Natural Convection

Section: Chapter Questions

Problem 8.9P

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