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.).

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter1: Basic Modes Of Heat Transfer

Section: Chapter Questions

Problem 1.1P: 1.1 On a cold winter day, the outer surface of a 0.2-m-thick concrete wall of a warehouse is exposed...

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