To8.2212T₁31.2.3.4" Common Brick1/2" OSB Sheathing3-1/2" x 1-1/2" (2x4) Yellow PineStudding placed on 16" center4.5.3-1/2" Figerglass Insulation1/2" DrywallA wall of a house as shown in theaccompanying sketch is 10 ft. high and 30ft. long and has no windows. The outsideheat transfer coefficient, h., is 6.0 Btu/hrft2°F and the inside convective heat transfercoefficient hi is 1.45 Btu/hr ft²°F.6.Calculate the heat loss through thewall if the house is heated such that theroom air temperature, Ti, is 70°F on a daywhen the outside air temperature, T., is 0°F.State all assumptions and list the thermalresistances and thermal conductivities foreach selection of the wall.For this problem, what would be the7.value of the overall heat transfer coefficient, U?Ans: U = 0.056 Btu/hr ft2°FYou are asked to design a metal hot dog holder for roasting hot dogs over an opencampfire. The holder is to be designed such that while the end holding the hot dogbecomes cherry red (1400°F), the other end can still be held without using aninsulated handle or glove (~95°F). Design it such that it can be used even on awarm, still day, T₁ = 90°F (Assume the convective heat transfer coefficient, h, fora horizontal cylinder is uniform over the whole cylinder and equal to 4.0Btu/hrft2°F)

To Find : The heat loss through the wall. Given : The thermal conductivity of materials are, For…

To Z 1 2 T₁ 1. 2. 3. 4" Common Brick 1/2" OSB Sheathing 3-1/2" x 1-1/2" (2x4) Yellow Pine Studding placed on 16" center 4. 5. 3-1/2" Figerglass Insulation 1/2" Drywall A wall of a house as shown in the accompanying sketch is 10 ft. high and 30 ft. long and has no windows. The outside heat transfer coefficient, h., is 6.0 Btu/hr ft2°F and the inside convective heat transfer coefficient hi is 1.45 Btu/hr ft²°F. 6. Calculate the heat loss through the wall if the house is heated such that the room air temperature, Ti, is 70°F on a day when the outside air temperature, T., is 0°F. State all assumptions and list the thermal resistances and thermal conductivities for 3 each selection of the wall.

To Z 1 2 T₁ 1. 2. 3. 4" Common Brick 1/2" OSB Sheathing 3-1/2" x 1-1/2" (2x4) Yellow Pine Studding placed on 16" center 4. 5. 3-1/2" Figerglass Insulation 1/2" Drywall A wall of a house as shown in the accompanying sketch is 10 ft. high and 30 ft. long and has no windows. The outside heat transfer coefficient, h., is 6.0 Btu/hr ft2°F and the inside convective heat transfer coefficient hi is 1.45 Btu/hr ft²°F. 6. Calculate the heat loss through the wall if the house is heated such that the room air temperature, Ti, is 70°F on a day when the outside air temperature, T., is 0°F. State all assumptions and list the thermal resistances and thermal conductivities for 3 each selection of the wall.

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 1.3P: 1.3 A furnace wall is to be constructed of brick having standard dimensions of Two kinds of...

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For your company you need to mass produce 20-cmx10-cm heat sinks to dissipate heat quickly from an equipment. After considering several other parameters, you have short-listed two possible designs: A. 72 straight pin fins made of an alloy (thermal conductivity 240 W/m-°C) that costs $9,000 per m³. Each pin is 4 cm long and 1-cm diameter. E.=3'18; $204 B. 64 straight rectangular fins made of another alloy (thermal conductivity 180 W/m.°C) that costs $12,000 per m³. Each pin is 4 cm long and has 2-cmx1-cm cross-section. Eo =7:94%$ 6·14 The convection coefficient of the operating condition is approximated as 15 W/m2.°c. Consider that the manufacturing cost is same for both designs but the material cost differs. Calculate and compare the cost and performance (in terms of heat transfer gains by the heat sinks) of the two heat sinks so that a decision can be made to select a design.
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To 8. Ti 1. 2. 3. 4" Common Brick 1/2" OSB Sheathing 3-1/2" x 1-1/2" (2x4) Yellow Pine Studding placed on 16" center 4. 5. 3-1/2" Figerglass Insulation 1/2" Drywall A wall of a house as shown in the accompanying sketch is 10 ft. high and 30 ft. long and has no windows. The outside heat transfer coefficient, h., is 6.0 Btu/hr ft2°F and the inside convective heat transfer coefficient hi is 1.45 Btu/hr ft2°F. 6. Calculate the heat loss through the wall if the house is heated such that the room air temperature, Ti, is 70°F on a day when the outside air temperature, T., is 0°F. State all assumptions and list the thermal resistances and thermal conductivities for 3 each selection of the wall. 7. For this problem, what would be the value of the overall heat transfer coefficient, U? Ans: U = 0.056 Btu/hr ft2ºF You are asked to design a metal hot dog holder for roasting hot dogs over an open campfire. The holder is to be designed such that while the end holding the hot dog becomes cherry red…
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c) A steel pipe of 100 mm bore, and 10 mm bore thickness, carrying dry saturated steam at 28 bars, is insulated with a 40 mm layer of moulded insulation. This insulation in turn is insulated with a 60 mm layer of felt. The atmospheric temperature is 15 °C. Calculate: (i) the rate of heat loss by the steam per metre pipe length. (ii) the temperature of the outside Dimensions in mm surface.zzzzzzz h₂-15 W/m²K Steel k₁=50 W/mK AVALEHT Ø100 1₂ " Steam 28 bar h-550 W/m²K, Inner heat transfer coefficient = 550 W/m² K Outer heat transfer coefficient = 15 W/m² K Thermal conductivity of steel = 50 W/m K Thermal conductivity of felt = 0.07 W/m K Moulded insulation Felt Moulded insulation K₂=0.09 W/mK Thermal conductivity of moulded insulation = 0.09 W/m 40 10. A 60 15°C Felt K₁=0.07 W/mK zzzzzzzz