The wall of a furnace comprises three layers as shown in the figuie. The first layer istery (whose maximum allowable temperature is 1400°C) while the second laver isTracto:y Chose maximum allowable temperature is 1093°C). The third layer is a plate of 6 35od thermal contact.Steet plareTo6.35x345A1370 CConcerntiationveluciy37.8 Cmass SiynesFigure. Layers in a composite furnace wall.e temperature To on the inside of the refractory is 1370°C, while the temperature T; on theside of the steel plate is 37.8° The heat loss through the furnace HnIlisexpectet tobe 14440&7%6.4.3UYTQKtabcaps lockVCshift 115800 W/m. Using the method of thermat resistance or otherwise, determine the thickness ofrefractory and insulation that results in the minimum total thickness of the walł.Expトshown on tiGiven thermal conductivities of refractory and insulation in W/(m K):Layer2 st 378k at 37.8°C k at 1093°CRefractory3.126.233.12Insulation1.563.12ニ(i)What is the maximum attainable temperature of the refractory?What is the maximum attainable temperature of the insulator?3.12(ii)1.56(ii)Considering the insulation being used, what is the temperature T2(iv)Calculate the temperature T2?+3.1204.120Acet.(v)What is temperature To?(vi)+61determune the value of k at temperature To.refractoryinsulator

Answered: Image /qna-images/answer/e00c5ec3-a8dc-4ce7-99ec-6ea4497f66f8.jpg

Retractory brick Insulating brick The vall ofa furnace comprises three layers as shown in the figure. The first layer is (yhose maximum allowable temperature is 1400°C) while the second layer is Tracto:y hose maximum allowable temperature is 1093°C). The third layer is a plate of 6.35 hickness of steel [thermal conductivity =45 W/(m K)]. Assume the lavers to be in ve od thermal contact. 6.35x3 Steet plare TA 45A こ. 1370 C 37.8 C concerntiation velbciy mass Siynes Figure. Layers in a composite furnace wall. e temperature To on the inside of the refractory is 1370°C, while the temperature T; on the side of the steel plate is 37.8°C The heat loss through the furnaceHnIlisexpectet to be Peu/cse/427 12

Retractory brick Insulating brick The vall ofa furnace comprises three layers as shown in the figure. The first layer is (yhose maximum allowable temperature is 1400°C) while the second layer is Tracto:y hose maximum allowable temperature is 1093°C). The third layer is a plate of 6.35 hickness of steel [thermal conductivity =45 W/(m K)]. Assume the lavers to be in ve od thermal contact. 6.35x3 Steet plare TA 45A こ. 1370 C 37.8 C concerntiation velbciy mass Siynes Figure. Layers in a composite furnace wall. e temperature To on the inside of the refractory is 1370°C, while the temperature T; on the side of the steel plate is 37.8°C The heat loss through the furnaceHnIlisexpectet to be Peu/cse/427 12

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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