A long rod of AISI 4130 steel initially at a uniform temperature of 400°C is suddenly exposed to 20°C air, where the heat transfer coefficient is 15 W/m2 ∙K. The rod has a diameter of 4.8 cm. How long after being exposed to the 20°C air will the steel rod reach a temperature of 60°C? The properties of the rod are p = 7840 kg/m3 , Cp = 460 J/kg.K and k = 43 W

A long rod of AISI 4130 steel initially at a uniform temperature of 400°C is suddenly exposed to 20°C air, where the heat transfer coefficient is 15 W/m2 ∙K. The rod has a diameter of 4.8 cm. How long after being exposed to the 20°C air will the steel rod reach a temperature of 60°C? The properties of the rod are p = 7840 kg/m3 , Cp = 460 J/kg.K and k = 43 W

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 3.16P: 3.16 A large, 2.54-cm.-thick copper plate is placed between two air streams. The heat transfer...

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