answers are shown in square brackets please answer all parts including Q13 Q12. The data below is for the wall in a building:ItemBrickinsulationHeavy concrete blockplasterexternal surfacethickness (mm) conductivity(W/mK)internal surface10525The heat transfer coefficients for the surfaces are:convectiveradiantconvectiveradiant20013The wall has a surface area of 10 m².(a) Determine:0.840.0350.250.1618 W/m²K4.5 W/m²K3.0 W/m²K5.0 W/m²Ki. the total resistance of the wall (R₁)[0.189 K/W]ii.the U value of the wall[0.53 W/m²K](b) when the temperature indoors is 20°C and the temperature outdoors is1°C, determine:(c) the rate of heat loss through the wall(d) the temperature of the inside surface of the wall[100 W][18.7 °C]Q13. What should the thickness of insulation in the above wall be increased toso as to give a 50% reduction in U value and what would be the newinside surface temperature?[91 mm, 19.4°C]

Answered: Image /qna-images/answer/bab1b4f4-2e21-48fb-b675-6d9b58c08c70.jpg

Q12. The data below is for the wall in a building: Item external surface Brick insulation Heavy concrete block plaster The heat transfer coefficients for the surfaces are: convective radiant convective radiant internal surface thickness (mm) conductivity (W/mK) 105 25 200 13 i. ii. The wall has a surface area of 10 m². (a) Determine: 0.84 0.035 0.25 0.16 18 W/m²K 4.5 W/m²K 3.0 W/m²K 5.0 W/m²K the total resistance of the wall (R₁) [0.189 K/W] [0.53 W/m²K] the U value of the wall (b) when the temperature indoors is 20°C and the temperature outdoors is 1°C, determine: (c) the rate of heat loss through the wall (d) the temperature of the inside surface of the wall [100 W] [18.7 °C] Q13. What should the thickness of insulation in the above wall be increased to so as to give a 50% reduction in U value and what would be the new inside surface temperature? [91 mm, 19.4°C]

Q12. The data below is for the wall in a building: Item external surface Brick insulation Heavy concrete block plaster The heat transfer coefficients for the surfaces are: convective radiant convective radiant internal surface thickness (mm) conductivity (W/mK) 105 25 200 13 i. ii. The wall has a surface area of 10 m². (a) Determine: 0.84 0.035 0.25 0.16 18 W/m²K 4.5 W/m²K 3.0 W/m²K 5.0 W/m²K the total resistance of the wall (R₁) [0.189 K/W] [0.53 W/m²K] the U value of the wall (b) when the temperature indoors is 20°C and the temperature outdoors is 1°C, determine: (c) the rate of heat loss through the wall (d) the temperature of the inside surface of the wall [100 W] [18.7 °C] Q13. What should the thickness of insulation in the above wall be increased to so as to give a 50% reduction in U value and what would be the new inside surface temperature? [91 mm, 19.4°C]

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 1.82P: Discuss the modes of heat transfer that determine the equilibrium temperature of the space shuttle...

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