Structure principle of air conditioning refrigeration

The principle of air conditioning refrigeration is:

Air-conditioning refrigeration uses the heat absorption when liquid vaporizes and the heat release effect when condensing to realize refrigeration. Liquid evaporates to form steam. When the liquid (refrigerant) is in a closed container, there is no other gas except the vapor generated by the liquid and the liquid itself, and the liquid and the vapor will reach equilibrium under a certain pressure. The steam at this time is called saturated steam, the pressure is called saturated pressure, and the temperature is called saturated temperature.

When the liquid is in equilibrium, it will no longer evaporate. At this time, if a part of steam is pumped out of the container, the liquid will inevitably continue to vaporize to generate a part of steam to maintain this balance.

When a liquid vaporizes, it absorbs heat, which is called latent heat of vaporization. The latent heat of vaporization comes from the cooled object, which makes the cooled object cool. In order to make this process continue, it is necessary to continuously extract steam from the container and condense it into liquid before returning to the container.

Schematic diagram of refrigeration is as follows:

Extended data

Principle of air conditioning refrigeration

The compressor compresses gaseous Freon into high-temperature and high-pressure liquid Freon, and then sends it to the condenser (outdoor unit) for heat dissipation, and then becomes liquid Freon at room temperature and high pressure, so the outdoor unit blows out hot air.

Liquid Freon Sutra

When the capillary enters the evaporator (indoor unit), the space suddenly increases and the pressure drops, and the liquid freon will vaporize and become gaseous low-temperature freon, thus absorbing a lot of heat and the evaporator will become cold. The fan of the indoor unit will blow out indoor air from the evaporator, so the indoor unit will blow out cold air. Water vapor in the air will condense into water droplets when it meets a cold evaporator and flow out along the water pipe, which is why air conditioners produce water. ?

Then the gaseous freon returns to the compressor to continue the compression cycle.

When heating, there is a component called four-way valve, which makes the flow direction of freon in condenser and evaporator opposite to that in refrigeration, so when heating, cold air is blown outdoors and hot air is blown indoors.

In fact, it is the principle that junior high school physics has learned that heat is discharged when liquefied (from gas to liquid) and heat is absorbed when vaporized (from liquid to gas).

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