Consider a thick spherical wall with insulation at boththe inner and outer walls. The inner and outer radii of the 3-layersphere are 1₂ = 40 cm and r3 = 80 cm, respectively. Thelength of cylinder is 1 meter. The thermal conductivity of the wallis k₂= 120- 0 . The thickness of outer insulation is 5 cm and itswallk2 = 120 W/mKb.c.r3= 80 cm2 = 40 cmWthermal conductivity is k3 = 12 . The thickness of the innerinsulation is also 5 cm, but the thermal conductivity is k₁ =W8 The heat dissipates through the surface of outer sides ofmkthe insulation through convention with ho = 50. and theWm²Kambient temperature outside the pipe is To = 25°C. The inner most surface is maintained at100°C. Use resistance models to solve this problem.a. Compute the heat transfer through the wallr1 = 35 cminner insulationk1 = 8 W/mKr4 = 85 cmouter insulationk3 = 12 W/mKCompute the temperature of the outer most surface of the sphereCompute the heat transfer when thickness the outer most insulator is quadrupled - sothe outer most radius r4 = 100 cm. Comparing to the previous outcome (part a), doesthe heat transfer rate make sense?

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Consider a thick spherical wall with insulation at both mk mk the inner and outer walls. The inner and outer radii of the 3-layer sphere are ₂ = 40 cm and r3 = 80 cm, respectively. The length of cylinder is 1 meter. The thermal conductivity of the wall is k₂ = 120 . The thickness of outer insulation is 5 cm and its thermal conductivity is k3 = 12 The thickness of the inner insulation is also 5 cm, but the thermal conductivity is k₁ = 8 The heat dissipates through the surface of outer sides of the insulation through convention with ho = 50- and the ambient temperature outside the pipe is Too = 25°C. The inner most surface is maintained at 100°C. Use resistance models to solve this problem. mk W m²K a. Compute the heat transfer through the wall b. Compute the temperature of the outer most surface of the sphere wall k2 = 120 W/mK r3=80 cm 2 = 40 cm r1 = 35 cm inner insulation k1 = 8 W/mK r4 = 85 cm outer insulation k3= 12 W/mK

Consider a thick spherical wall with insulation at both mk mk the inner and outer walls. The inner and outer radii of the 3-layer sphere are ₂ = 40 cm and r3 = 80 cm, respectively. The length of cylinder is 1 meter. The thermal conductivity of the wall is k₂ = 120 . The thickness of outer insulation is 5 cm and its thermal conductivity is k3 = 12 The thickness of the inner insulation is also 5 cm, but the thermal conductivity is k₁ = 8 The heat dissipates through the surface of outer sides of the insulation through convention with ho = 50- and the ambient temperature outside the pipe is Too = 25°C. The inner most surface is maintained at 100°C. Use resistance models to solve this problem. mk W m²K a. Compute the heat transfer through the wall b. Compute the temperature of the outer most surface of the sphere wall k2 = 120 W/mK r3=80 cm 2 = 40 cm r1 = 35 cm inner insulation k1 = 8 W/mK r4 = 85 cm outer insulation k3= 12 W/mK

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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