Refrigeration principle and use suggestion of refrigerator


People often ask what is the refrigeration principle of […]

People often ask what is the refrigeration principle of a refrigerator? The temperature in the refrigerator has dropped, so where is the heat in the refrigerator? Isn't this a violation of the law of conservation of energy? Where is the electricity consumed by the refrigerator? Will it be directly cooled as fast as it is hot? Faced with so many questions, I summarized them and got the following answers.

Where did the heat absorbed by the refrigerator go
The heat in the refrigerator compartment and freezer compartment of the refrigerator is dissipated into the room through the outer wall of the refrigerator. This is a process of energy transfer and does not violate the conservation of energy. At the same time, the heat dissipated into the room also includes the heat generated when the equipment inside the refrigerator works.
Therefore, some people open the refrigerator door and want to cool the room in this way, it is not feasible: the heat dissipation of the refrigerator = the refrigeration capacity of the refrigerator + the heat generated by the refrigerator. So the more you open the refrigerator door, the higher the indoor temperature.

Where is the electricity consumed by the refrigerator
In the refrigerator system, electrical energy does not participate in refrigeration, it only provides power for the refrigerant-the refrigerator wants to be cooled, the refrigerant must constantly move in the pipeline, which we will say later.
For example, the electrical energy here is like gasoline in a car. It is the engine that actually drives the car, but gasoline provides energy to the engine.

Principles of refrigerator refrigeration
We regard the refrigerator as two parts: inside and outside the refrigerator. The main function of the device in the refrigerator is to absorb heat, that is, cooling. Its main device is an evaporator. The function of the device outside the refrigerator is to dissipate heat and provide power. Its main devices are the compressor, condenser and capillary tube.
Here we focus on the refrigeration principle of the refrigerant. It is not like we think, it is by reducing its temperature to achieve the endothermic effect. Instead, a physical phenomenon is used-the liquid boils and absorbs heat. Why can the liquid refrigerant in the refrigerator boil? This is another physical knowledge-the lower the pressure, the lower the boiling point.

Gaseous refrigerant passes through the condenser and meets the capillary tube, but the capillary tube is relatively thin, causing a large amount of refrigerant to crowd in the condenser. One pushes towards the capillary (compressor), and the other is blocked (capillary), and more and more refrigerant is trapped in the condenser, and the pressure becomes greater and greater.

After the pressure increases, the gaseous refrigerant begins to liquefy, and the liquefaction process is accompanied by heat absorption, so the refrigerant remaining in the first half of the condenser (near the compressor) is the high-temperature and high-pressure liquid. These refrigerants slowly cool down in the condenser until they reach room temperature and begin to line up slowly through the capillary.

The tube of the evaporator is thick, and the pressure of the refrigerant passing through the capillary suddenly decreases, so the liquid refrigerant starts to boil and vaporize (with heat absorption). Until the refrigerant completely passes through the evaporator, it also becomes a gaseous state at normal temperature and pressure.

The gaseous refrigerant passes through the compressor again and continues a new cycle.

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