QUESTION 2The wall of a refrigerated truck consists of 1.5mm sheet steelouter surface, 10mm plywood at the inner surface and 20mmof glass wool in between. The inside temperature is -15°Cand outside temperature is 24°C. Take the thermalconductivities of the materials as follows: -=0,052W/mK= 23,2W/mKk for glass-wool = 0,14W/mKk for plywoodk for steel%3DCalculate:2.1. the rate of heat flow per unit area;2.2. the interface temperature.If the glass-wool is replaced by a 5mm cork board with athermal conductivity of 0.043W/mK;2.3. What percentage change in heat flow is obtained?2.4. What must be the thickness of the cork board be, toachieve the same heat flow as in (2.1.).

Answered: Image /qna-images/answer/c5d6fd48-ac5a-40b8-ae61-737632c231e2.jpg

QUESTION 2 The wall of a refrigerated truck consists of 1.5mm sheet steel outer surface, 10mm plywood at the inner surface and 20mm of glass wool in between. The inside temperature is -15°C and outside temperature is 24°C. Take the thermal conductivities of the materials as follows: - k for plywood k for steel k for glass-wool = 0,052W/mK = 23,2W/mK = 0,14W/mK %3D %3D Calculate: 2.1. the rate of heat flow per unit area; 2.2. the interface temperature. If the glass-wool is replaced by a 5mm cork board with a thermal conductivity of 0.043W/mK; 2.3. What percentage change in heat flow is obtained? 2.4. What must be the thickness of the cork board be, to achieve the same heat flow as in (2.1.).

QUESTION 2 The wall of a refrigerated truck consists of 1.5mm sheet steel outer surface, 10mm plywood at the inner surface and 20mm of glass wool in between. The inside temperature is -15°C and outside temperature is 24°C. Take the thermal conductivities of the materials as follows: - k for plywood k for steel k for glass-wool = 0,052W/mK = 23,2W/mK = 0,14W/mK %3D %3D Calculate: 2.1. the rate of heat flow per unit area; 2.2. the interface temperature. If the glass-wool is replaced by a 5mm cork board with a thermal conductivity of 0.043W/mK; 2.3. What percentage change in heat flow is obtained? 2.4. What must be the thickness of the cork board be, to achieve the same heat flow as in (2.1.).

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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Conduction and Convection

When energy travels from one object to another it is said to have undergone heat transfer. Heat transfer is nothing but the transfer of thermal energy or internal energy from one thing to another, like e.g., when a vessel with water, kept on top of a burner, heats up because of the flame underneath it.

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