there is no radius only given thickness A composite cylinder is made of two materials, each 6 mm in thickness and thermalconductivities of 30 W / mC and 45 W/ mC respectively. Steam passes through the cylinder at500°C with a convection coefficient of 40 W / m?C. The cylinder is open to air environmentwith a temperature of 35BC and a convection coefficient of 25 W / m?C. Calculate the heatenergy lost from the 2 m length of the cylinder.

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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.

Chapter6: Forced Convection Over Exterior Surfaces

Section: Chapter Questions

Problem 6.36P

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The flames in an industrial furnace burn at 800°C on average and the convection coefficientbetween the hot gas and the inside wall of the furnace is ℎ1 = 30 W m2–K⁄ . The wall of thefurnace is made of steel (?? = 20 W m–K⁄ ) and is ? = 10 cm thick. To ensure nobody willburn themself on the exterior surface of the furnace, the steel is to be covered by aninsulating material with a low thermal conductivity (?? = 0.05 W m–K⁄ ). The airsurrounding the furnace is at 27°C and free convection on the exterior wall of the furnaceis expected to produce a convection coefficient of ℎ = 5 W/m2–K. Any radiation effects areexpected to be negligible in this analysis.a) If safety standards require that the outer surface of the furnace not exceed 65°C, howthick should the insulation layer be? This problem is most straightforward if youleverage the concept of thermal resistance.b) Using your result from part (a), calculate the overall heat transfer coefficient (?)from the furnace gas to the ambient…