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4. In the winter a house loses heat at an average rate of 1 kW from...
Problem 2 Consider a house that is approximated as a cube that is 7 m on...
Problem 2 Consider a house that is approximated as a cube that is 7 m on a side and has no windows. The house loses heat from the four walls and the roof. For an inside temperature of 25°C and an outside temperature of -25°C, it is desired to keep the total heat loss less than 5 kW. What is the minimum RSI-value that is required for the walls and roof?
Consider a house that has a 10-m x 20-m base and a 4-m-high wall. All four...
Consider a house that has a 10-m x 20-m base and a 4-m-high wall. All four walls of the house have an R-value of 2.31m2°C/W. The two 10-m x 4-m walls have no windows. The third wall has five windows made of 0.5-cm-thick glass (k = 0.78 W/m-K), 1.2m x 1.8min size. The fourth wall has the same size and number of windows, but they are double paned with a 1.5-cm-thick stagnant air space (k = 0.026 W/m-K) enclosed between...
7a) Consider a room in a house that has composite walls with an Rtt-1.5 m2K/W. The...
7a) Consider a room in a house that has composite walls with an Rtt-1.5 m2K/W. The total cross sectional area of the walls is 35 m During winter, the temperature outside the room is Tout5°C. Inside the room, there is an electric heater that emits heat at a rate of 200 W The room is occupied by 2 people that emit heat at a rate 80 W each. What is the temperature inside the room (in °C)? Express your answer...
During 4 hours one winter afternoon, when the outside temper (a) what was the average energy...
During 4 hours one winter afternoon, when the outside temper (a) what was the average energy leakage in youles per second (watts) through the walls of the house to the environment (the outside air and rature was 11°C, a house heated by electricity was kept at 21°C with the expenditure of 57 kwh (kilowatt-hours) of electric energy ground,? (b) The rate at which energy is transferred between two systems due to a temperature had been kept at 23 C (73.4"F),...
5, (25 points) A Carnot heat pump is used to maintain a house at 20 °C...
5, (25 points) A Carnot heat pump is used to maintain a house at 20 °C in winter and consumes 8 kW of power (electricity) when operating. On a day temperature outside the house is -3 °C, the house is estimated to lose heat at an average rate of 80,000 kJ/h. (Sa). (2p) Please identify the hot reservoir and the cool reservoir of this heat pump. (5b). (2p) Please draw of schematic diagram of this heat pump-house heating system with...
Heat Loss and Heating Costs of a House Part A A house has well-insulated walls 17.1...
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...
02. [HW] Textbook problem 6-160 (6 marks) A heat pump receives heat from a lake that...
02. [HW] Textbook problem 6-160 (6 marks) A heat pump receives heat from a lake that has an average winter time temperature of 6°C and supplies heat into a house having an average temperature of 27° C. (a) If the house loses heat to the atmosphere at a rate of 64000 kJ/h, determine the minimum power supplied to the heat pump, in kW. (b) A heat exchanger is used to transfer the energy from the lake water to the heat...
(a) Calculate the rate of heat conduction through house walls that are 13.0 cm thick and...
(a) Calculate the rate of heat conduction through house walls that are 13.0 cm thick and that have an average thermal conductivity twice that of glass wool. Assume there are no windows or doors. The surface area of the walls is 120m2 and their inside surface is at 18.0ºC, while their outside surface is at 5.00ºC (b) How many 1-kW room heaters would be needed to balance the heat transfer due to conduction?
(a) Calculate the rate of heat conduction through house walls that are 15.5 cm thick and...
(a) Calculate the rate of heat conduction through house walls that are 15.5 cm thick and that have an average thermal conductivity twice that of glass wool. Assume there are no windows or doors. The surface area of the walls is 125 m2 and their inside surface is at 21.0°C, while their outside surface is at 5.00°C. W (b) How many 1-kW room heaters would be needed to balance the heat transfer due to conduction? (Round your answer to the...
(a) Calculate the rate of heat conduction (in W) through house walls that are 11.5 cm...
(a) Calculate the rate of heat conduction (in W) through house walls that are 11.5 cm thick and that have an average thermal conductivity twice that of glass wool. Assume there are no windows or doors. The surface area of the walls is 145 m2 and their inside surface is at 22.5°C, while their outside surface is at 5.00°C. (b) How many 1 kW room heaters would be needed to balance the heat transfer due to conduction? (Round your answer...
Problem 2 Consider a house that is approximated as a cube that is 7 m on a side and has no windows. The house loses heat from the four walls and the roof. For an inside temperature of 25°C and an outside temperature of -25°C, it is desired to keep the total heat loss less than 5 kW. What is the minimum RSI-value that is required for the walls and roof?
Consider a house that has a 10-m x 20-m base and a 4-m-high wall. All four walls of the house have an R-value of 2.31m2°C/W. The two 10-m x 4-m walls have no windows. The third wall has five windows made of 0.5-cm-thick glass (k = 0.78 W/m-K), 1.2m x 1.8min size. The fourth wall has the same size and number of windows, but they are double paned with a 1.5-cm-thick stagnant air space (k = 0.026 W/m-K) enclosed between...
7a) Consider a room in a house that has composite walls with an Rtt-1.5 m2K/W. The total cross sectional area of the walls is 35 m During winter, the temperature outside the room is Tout5°C. Inside the room, there is an electric heater that emits heat at a rate of 200 W The room is occupied by 2 people that emit heat at a rate 80 W each. What is the temperature inside the room (in °C)? Express your answer...
During 4 hours one winter afternoon, when the outside temper (a) what was the average energy leakage in youles per second (watts) through the walls of the house to the environment (the outside air and rature was 11°C, a house heated by electricity was kept at 21°C with the expenditure of 57 kwh (kilowatt-hours) of electric energy ground,? (b) The rate at which energy is transferred between two systems due to a temperature had been kept at 23 C (73.4"F),...
5, (25 points) A Carnot heat pump is used to maintain a house at 20 °C in winter and consumes 8 kW of power (electricity) when operating. On a day temperature outside the house is -3 °C, the house is estimated to lose heat at an average rate of 80,000 kJ/h. (Sa). (2p) Please identify the hot reservoir and the cool reservoir of this heat pump. (5b). (2p) Please draw of schematic diagram of this heat pump-house heating system with...
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...
02. [HW] Textbook problem 6-160 (6 marks) A heat pump receives heat from a lake that has an average winter time temperature of 6°C and supplies heat into a house having an average temperature of 27° C. (a) If the house loses heat to the atmosphere at a rate of 64000 kJ/h, determine the minimum power supplied to the heat pump, in kW. (b) A heat exchanger is used to transfer the energy from the lake water to the heat...
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