4-26 Steel rods (p = 7832 kg/m³, c, = 434 J/kg -K, and k = 63.9W/m-K) are heated in a furnace to 850°C and then quenched in a water bath at 50°C for a period of 40 s as part of a hardening process. The convection heat transfer coefficient is 650 W/m² K. If the steel rods have diameter of 40 mm and length of 2 m, determine their average temperature when they are taken out of the water bath.

4-26 Steel rods (p = 7832 kg/m³, c, = 434 J/kg -K, and k = 63.9W/m-K) are heated in a furnace to 850°C and then quenched in a water bath at 50°C for a period of 40 s as part of a hardening process. The convection heat transfer coefficient is 650 W/m² K. If the steel rods have diameter of 40 mm and length of 2 m, determine their average temperature when they are taken out of the water bath.

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.

Chapter3: Transient Heat Conduction

Section: Chapter Questions

Problem 3.3P

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