4-57 A long steel bar 5 by 10 cm is initially maintained at a uniform temperature of250°C. It is suddenly subjected to a change such that the environment temperatureis lowered to 35°C. Assuming a heat-transfer coefficient of 23 W/m2 . °C, use anumerical method to estimate the time required for the center temperature to reach90°C. Check this result with a calculation using the Heisler charts.

given:length of steel bar =5/10cmTi=2500Cenviroment temperature T∞=350Cfrom table K=43W/mkheat…

Answered: - 10 cm is initially main subjected to…

Engineering

Mechanical Engineering

- 10 cm is initially main subjected to a change su Assuming a heat-transfer

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.

Chapter2: Steady Heat Conduction

Section: Chapter Questions

Problem 2.4P: A plane wall 15 cm thick has a thermal conductivity given by the relation k=2.0+0.0005T[W/mK] where...

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