An aluminum alloy sphere 10cm in diameter has a uniform temperature of 200°C after being removed from a hot oven. The aluminum sphere is then left in a cold room of 15°C and being blown by forced air. The convection heat transfer coefficient from the air flow is assumed to be h = 500 W/m²K Use the following properties to solve the problem: k = 163 W/mK, p = 2810 kg/m³, Cp = 880J/kg°C. a. Using Lump Model, determine the temperature of the sphere after 2 minutes. b. Determine the required convective heat transfer (h) to cool the sphere from 200°C to 80°C in 3 minutes.

An aluminum alloy sphere 10cm in diameter has a uniform temperature of 200°C after being removed from a hot oven. The aluminum sphere is then left in a cold room of 15°C and being blown by forced air. The convection heat transfer coefficient from the air flow is assumed to be h = 500 W/m²K Use the following properties to solve the problem: k = 163 W/mK, p = 2810 kg/m³, Cp = 880J/kg°C. a. Using Lump Model, determine the temperature of the sphere after 2 minutes. b. Determine the required convective heat transfer (h) to cool the sphere from 200°C to 80°C in 3 minutes.

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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