In a manufacturing process a thin rectangular part that has a surface area of 30 cm × 30 cm and a mass of 3750 g and is initially at 498 K. The part is left to cool in ambient at room temperature (T¥=Tsurr=25 °C) with a convection heat transfer coefficient of 6.40 W/m2·K. The part can be assumed to have a specific heat of 2.770 kJ/kg·K. If the surface emissivity is 0.42 what is the initial rate of change in temperature as the part cools in ambient? What is the initial rate of heat loss by radiation and convection? (Evaluate each separately).

In a manufacturing process a thin rectangular part that has a surface area of 30 cm × 30 cm and a mass of 3750 g and is initially at 498 K. The part is left to cool in ambient at room temperature (T¥=Tsurr=25 °C) with a convection heat transfer coefficient of 6.40 W/m2·K. The part can be assumed to have a specific heat of 2.770 kJ/kg·K. If the surface emissivity is 0.42 what is the initial rate of change in temperature as the part cools in ambient? What is the initial rate of heat loss by radiation and convection? (Evaluate each separately).

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 1.60P: 1.60 Two electric resistance heaters with a 20 cm length and a 2 cm diameter are inserted into a...

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1.60 Two electric resistance heaters with a 20 cm length and a 2 cm diameter are inserted into a well-insulated 40-L tank of water that is initially at 300 K. If each heater dissipates 500 W, what is the time required for bringing the water temperature in the tank to 340 K? State your assumption for your analysis.
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