The attic of a house is insulated with 15-cm thick cellulose insulation. If the cellulose ls...
Heat Loss and Heating Costs of a House Part A A house has well-insulated walls 17.1 cm thick (assume conductivity of air) and area 411 m2, a roof of wood б.бб cm thick and area 279 m2, and uncovered windows 0.626 cm thick and total area 33.4 m2. Assuming that the heat loss is only by conduction, calculate the rate at which heat must be supplied to this house to maintain its temperature at 21.4°C if the outside temperature is...
A house has a composite wall of wood, fiberglass insulation, and
plaster board, as indicated in the sketch. On a cold day, the
temperature and the convection heat transfer coefficients are T∞,i
=20°C, hi =30 W/m2K and T∞,o=−15°C, ho =60 W/m2K. The wall surface
area is 350 m2. Determine the total heat loss through the wall.
Conductivities are given as b k =0.038 W/m.K, s k =0.012 W/m.K, p k
=0.17 W/m.K
Glass fiber blanket (28 kg/m3), kn Plaster board,...
Heat Transfer
-A wall 20 cm thick is to be constructed from material that has an average thermal conductivity of 2 W/m C. The wall is to be insulated with 5cm material having an average thermal conductivity of 0.5W/m C. Assuming that the inner and outer surface temperatures of the insulated wall are 200 and 20°C, calculate the heat transfer per unit area and the intermediate Temperature between the insulation and the wall.
The wall of a house is 3 m high, 10 m long and 30 cm thick; it has an effective thermal conductivity of 10 W/m K. The outer surface of the wall has an emissivity of 0.75. On a winter night, the outer surface of this wall is at a temperature of 0 °C and the air is at a temperature of –10 °C. The heat transfer coefficient for the outside wall is 8 W/m2 K. The outside wall also...
The boiling temperature of nitrogen at atmospheric pressure at sea level (1 atm pressure) is -196°C. Therefore, nitrogen is commonly used in low-temperature scientific studies since the temperature of liquid nitrogen in a tank open to the atmosphere will remain constant at -196°C until it is depleted. Any heat transfer to the tank will result in the evaporation of some liquid nitrogen, which has a heat of vaporization of 198 kJ/kg and a density of 810 kg/m3 at 1 atm....
Heat transfer, help me please
6- A 2.5 m-high, 4-m-wide, and 80-cm-thick wall of a house has a thermal resistance of 0.0125°c/W. The thermal conductivity of the wall is (a) 3.2 W/mK (b) 4.8 W/m-K (c) 6.4 W/m-K (d) 1.6 W/m-K (e) 32 W/m-K
A carpenter builds an exterior house wall with a layer of wood 2.9 cm thick on the outside and a layer of Styrofoam insulation 2.1 cm thick on the inside wall surface. The wood has k=0.080W/(m⋅K), and the Styrofoam has k= 0.010 W/(m⋅K). The interior surface temperature is 19.0 ∘C , and the exterior surface temperature is -10.0 ∘C . What is the temperature at the plane where the wood meets the Styrofoam?
A concrete wall of a house is 45 cm thick and has a surface area 20m x 5 m. The inside temperature of the wall is 47 °C and the outside air temperature is 14 °C. Thermal conductivity of the concrete wall is 0.8 W/mK. Calculate the heat transfer rate through the wall by conduction and its thermal resistance.
In this problem you will estimate the heat lost by a typical house, assuming that the temperature inside is T(in) = 20 degrees celcius and the temperature outside is T(out) = 0 degrees celcius. The walls have fiberglass insulation, which dominates the heat conduction properties of the wall So we can consider the wall to have a thermal conductivity of k(wall) = 0.048 W/m/K . We will take the thickness of the walls and ceiling to be L(wall) = 12...
In this problem, you will estimate the heat lost by a typical house, assuming that the temperature inside is Tin=20∘C and the temperature outside is Tout=0∘C. The walls and uppermost ceiling of a typical house are supported by 2×6 inch wooden beams (kwood=0.12W/(mK)) with fiberglass insulation (kins=0.04W/(mK)) in between. The thickness of the wall is Lwall=18cm allowing for interior and exterior covering. Assume that the house is a cube of length L=9.0m on a side. Approximate that the roof has...