Steel balls 12 mm in diameter are annealed by heating to 1100 K and then slowly cooling to 360 K in an air environment for wh To = 325 K and h = 20W/m2.K. Assuming the properties of the steel to be k = 40 W/m-K, p = 7800 kg/m³, and c = 600 /kg•K, estimate the time required for the cooling process.

Steel balls 12 mm in diameter are annealed by heating to 1100 K and then slowly cooling to 360 K in an air environment for wh To = 325 K and h = 20W/m2.K. Assuming the properties of the steel to be k = 40 W/m-K, p = 7800 kg/m³, and c = 600 /kg•K, estimate the time required for the cooling process.

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 3.36P

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