Q5A) Consider a composite spherical shell comprising an insulating layer of unknown thermalconductivity sandwiched between two layers of steel (k = 45 W/m. °C). The inner shell has100 mm inner diameter and wall thickness of 5 mm. The outer shell has 150 mm innerdiameter and wall thickness of 2 mm. The inner surface of inner spherical shell wasexperimentally found 120 °C while outer surface of outer spherical shell was at 67 °C. Theambient air was at 30 °C with heat-transfer coefficient at outer surface 6 W/m². °C. Determinethermal conductivity of insulating material. Then, experiment was repeated on another day whenambient air temperature was 13 °C. The inner surface temperature of inner shell and convectioncoefficient remained unchanged. Calculate temperature of outer surface of outer shell in this case.

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Answered: Q5A) Consider a composite spherical…

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 2.24P

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