Q4) A long steel bar 5 by 10 cm is initially maintained at a uniform temperature of 250 ". It is suddenly subjected to a change such that the environment temperature is lowered to 35 °C. Assuming a heat-transfer coefficient of 23 W/m² °C, use a numerical method to estimate the time required for the center temperature to reach 105 °C. Check this result with a calculation using the Heisler charts.

Q4) A long steel bar 5 by 10 cm is initially maintained at a uniform temperature of 250 ". It is suddenly subjected to a change such that the environment temperature is lowered to 35 °C. Assuming a heat-transfer coefficient of 23 W/m² °C, use a numerical method to estimate the time required for the center temperature to reach 105 °C. Check this result with a calculation using the Heisler charts.

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 3.13P

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