A steel ball [e0.46 kJ/kg. °C, k 35 W/m-°C] 5.0 cm in diameter and initially at a uniform temperature of 450°C is suddenly placed in a controlled environment in which the temperature is maintained at 100°C. The convection heat-transfer coefficient is 10 W/m °C. Calculate the time required for the ball to attain a temperature of 150°C.

A steel ball [e0.46 kJ/kg. °C, k 35 W/m-°C] 5.0 cm in diameter and initially at a uniform temperature of 450°C is suddenly placed in a controlled environment in which the temperature is maintained at 100°C. The convection heat-transfer coefficient is 10 W/m °C. Calculate the time required for the ball to attain a temperature of 150°C.

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.

Chapter1: Basic Modes Of Heat Transfer

Section: Chapter Questions

Problem 1.17P: The heat transfer rate from hot air by convection at 100C flowing over one side of a flat plate with...

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