plz show all work What is the difference between a refrigerator and air conditio

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What is the difference between a refrigerator and air conditioner? 7-3- C Define the coefficient of performance of a heat pump ixi words. Can it be greater than unity? A household refrigerator with a COP of 1.2 removes heat from the refrigerated space at a rate of 60 kJ/min. Determine (a) the electric power consumed by the refrigerator and (b) the rate of heat transfer to the kitchen air. Answers: te) 0.83 kW, (b) 110 kJ/min 7-54 Refrigerant-134a enters the condcn*>er of a residential heat pump at 800 kPa and 35*C at a rate of 0.018 ki?/s am] leaves at $00 kPa as a saturated liquid. If the compressor con sumcs 1.2 kW of power, determine (a) the COP of the ht-;il pump and (b) the rate of heat absorption from the outside air. 7-70C Consider two actual power plants operating with solar energy. Energy is supplied to one plant from a solar pond at 80^ and to the other from concentrating collectors that raise the water temperature to 600degreeC. Which of these power plants will have a higher efficiency? Explain. A heat engine is operating on a Carnot cycle and has a thermal efficiency of 75 percent. The waste hear from this engine is rejected to a nearby lake at 15"C at a rate of 14 kW. Determine the power output of the engine and the tempera- ture of the source, in CC. Answers: 42 kW. 879'C. A heat pump operates on a Carnot heat pump tyiic with a COP of 8.7. It keeps a space at 26degreeC by consuming 4.25 kW of power. Determine the temperature of the reservoir from which the heat is absorbed and the heating kui provided by the heal pump. Answers: 265 K, 37.0 kW A heal engine receives heat from a heat source 1200degreeC and rejects heat to a heat sink ai 50degreeC. The Ileal engine does maximum work equal to 500 kJ. Determine ilu¬teal supplied to the heat engine by the heat source and I he heat rejected to the heat sink.

Explanation / Answer

Air conditioners take higher load than refrigerators.
Air conditioners expel the heat out of the room, refrigerators only out of the refrigerator.
Air conditioners also filter the air.
Air conditioners finally cool the room, refrigerators cool the inside.
Better loss prevention in refrigerators. Air conditioners losses are comparatively high.
Air conditioners consume more power.

Functionally, both use a compressor to exhaust heat, then expand to cool the air.
An air conditioner has a fan that will push the air into the room you want to cool. The exhaust needs a path outside (via window or outdoor AC unit), otherwise the air condition won't be doing anything except heating and cooling the room at the same time.

A fridge will just cool the interior of its insulated container.
Functionally, its the same idea: cool air in one place by heating air in another.

Refrigerator decrease the temperature of the space(room or compartment) to a certain level while air conditioning just maintain the condition of the space at the comfortable state to humans by controlling both temperature and humidity.

The coefficient of performance or COP (sometimes CP) of a heat pump is a ratio of heating or cooling provided to electrical energy consumed. Higher COPs equate to lower operating costs. The COP may exceed 1, because it is a ratio of output:loss, unlike the thermal efficiency ratio of output:input energy. For complete systems, COP should include energy consumption of all auxiliaries. COP is highly dependent on operating conditions, especially absolute temperature and relative temperature between sink and system, and is often graphed or averaged against expected conditions

From the basic definition of coefficient of performance,we can compute= 0.83 kW..

From the cycle relationship between |QH|, |QL|, and |W|, |QH| = |QL| + |W|, we can write, for heat rates and power, . Thus we find that the heat rejected to the kitchen air is = 1.83 kW.

7-79

A heat engine is operating on a Carnot cycle and has a thermal efficiency of 55%. The waste heat from this engine is rejected to a nearby lake at 60oF at a rate of 800 Btu/min. Determine (a) the power output of the engine and (b) the temperature of the heat source.

We can combine the basic definition of cycle efficiency, , and the cycle relationship between |QH|, |QL|, and |W|, , to eliminate .

For this problem, where, and h = 55%, we can find the power output as follows.

= 23.1 hp.

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