A soldering iron has a cylindrical tip of 2.5 mm in diameter and 20 mm in length. With age and usage, the tip has oxidized and has an emissivity of 0.95. Assuming that the average convection heat transfer coefficient over the soldering iron tip is 35 W/m2-K, and the surrounding air temperature is 20°C, determine the power required to maintain the tip at 400°C. Air, 20°C T = 400°C D= 2.5 mm L= 20 mm

A soldering iron has a cylindrical tip of 2.5 mm in diameter and 20 mm in length. With age and usage, the tip has oxidized and has an emissivity of 0.95. Assuming that the average convection heat transfer coefficient over the soldering iron tip is 35 W/m2-K, and the surrounding air temperature is 20°C, determine the power required to maintain the tip at 400°C. Air, 20°C T = 400°C D= 2.5 mm L= 20 mm

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 8.34P

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