P8.1 A wall of a building is 15 m long and 4 m high. It has a 9 mm thick gypsum board (k = 0.16 Wm ¹K¹) on the inside. Next to it is a 140 mm thick layer of glass fiber insulation (k = 0.046 Wm¯¹K¯¹) which is followed by a 180 mm thick layer of concrete (k = 2.1 Wm¯¹K¯¹). The outer face is made brick (k = 1.35 Wm¯¹K¯¹) with a thickness of 100 mm. The outside and inside heat transfer coefficients are 28 Wm ²K¯¹ and 8 Wm 2K¹ respectively. The inside and outside air temperatures are 23°C and 2°C respectively. Calculate (i) the total thermal resistance, (ii) the overall heat transfer coefficient, and (iii) the total heat transfer rate through the wall. [Answers: (1) 3.42 m²KW¯¹. (ii) 0.293 Wm ²K¹. (iii) 369WI

P8.1 A wall of a building is 15 m long and 4 m high. It has a 9 mm thick gypsum board (k = 0.16 Wm ¹K¹) on the inside. Next to it is a 140 mm thick layer of glass fiber insulation (k = 0.046 Wm¯¹K¯¹) which is followed by a 180 mm thick layer of concrete (k = 2.1 Wm¯¹K¯¹). The outer face is made brick (k = 1.35 Wm¯¹K¯¹) with a thickness of 100 mm. The outside and inside heat transfer coefficients are 28 Wm ²K¯¹ and 8 Wm 2K¹ respectively. The inside and outside air temperatures are 23°C and 2°C respectively. Calculate (i) the total thermal resistance, (ii) the overall heat transfer coefficient, and (iii) the total heat transfer rate through the wall. [Answers: (1) 3.42 m²KW¯¹. (ii) 0.293 Wm ²K¹. (iii) 369WI

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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