(C) The composite wall of a refrigerator consists of three different materials; A, B, and C. Two of the used materials have known thermal conductivity, kA = 30 W/m. K and kc=45 W/m. K, and known thickness, La=0.20 m and Lc = 0.15 m. The third material, B, which is sandwiched between materials A and C, is of known thickness, LB =0.15 m, but unknown thermal conductivity kB. Under steady-state operating conditions, measurements reveal an outer surface temperature of Ts,o = 20°C, an inner surface temperature of Ts,i = 600°C, and a refrigerator air temperature of T∞ = 800°C. The inside convection coefficient h is known to be 25 W/m².K. What is the value of thermal conductivity for material B? ke kc Air T, h - LA Figure 2: Composite wall configuration described in part C.

(C) The composite wall of a refrigerator consists of three different materials; A, B, and C. Two of the used materials have known thermal conductivity, kA = 30 W/m. K and kc=45 W/m. K, and known thickness, La=0.20 m and Lc = 0.15 m. The third material, B, which is sandwiched between materials A and C, is of known thickness, LB =0.15 m, but unknown thermal conductivity kB. Under steady-state operating conditions, measurements reveal an outer surface temperature of Ts,o = 20°C, an inner surface temperature of Ts,i = 600°C, and a refrigerator air temperature of T∞ = 800°C. The inside convection coefficient h is known to be 25 W/m².K. What is the value of thermal conductivity for material B? ke kc Air T, h - LA Figure 2: Composite wall configuration described in part C.

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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