1. The composite wall of an oven consists of three materials, two of which are of known thermalconductivity, k₁ = 20 W/m • K and kc = 50 W/m • K, and known thickness, L₁ = 0.30 m and Lc =0.15 m. The third material, B, which is sandwiched between materials A and C, is of knownthickness, Lâ = 0.15 m, but the unknown thermal conductivity kú.-TspTs.iKAkBkg kcAirT, hUnder steady-state operating conditions, measurements reveal an outer surface temperature of Ts,o =20°C, an inner surface temperature of T¸¡ = 600°C, and an oven air temperature of T∞ = 800°C. Theinside convection coefficient h is known to be 25 W/m² • K. What is the value of k¸?Answer: KB=1.53W/m*K

Answered: 1. The composite wall of an oven…

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 2.63P

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