1) Air is flowing steadily through a cooling section where it is cooled from 86 °F...

1) Air is flowing steadily through a cooling section where it is cooled from 86 °F to 59 °F at a rate of 0.55 lbm/s. If the average COP of the air-conditioner is 2.8 and the unit cost of electricity is $0.07 per kWh, determine the cost of electricity consumed by this air-conditioner per day (24 hours).

2) A heat pump absorbs heat from the cold outdoors at 3 °C and supplies heat to a house at 20 °C at a rate of 30,000 kJ/h. If the power consumed by the heat pump is 3 kW, find the coefficient of performance of the heat pump.

3) A heat engine cycle is executed with steam in the saturation dome. The pressure of steam is 2 MPa during heat addition, and 0.1 MPa during heat rejection. Determine the highest possible efficiency of this heat engine.

4) A heat engine receives heat from a source at 800 °C and rejects the waste heat to a sink at 40 °C. If heat is rejected from this engine at a rate of 80 kJ/s, what is the maximum power this heat engine can produce?

Expert Solution

samet mamat answered 2 years ago

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