What is the main principle of operation of a refrigerator and an ordinary refrigeration unit?

The modern world is difficult to imagine without the achievements of scientific and technological progress and the development of civilization. Thanks to scientific discoveries, different types of energy became available to people, which benefit modern humanity. One of such revolutionary discoveries was the invention of a refrigeration unit in 1910 by the French physicist Marcel Odifren.

The principle of the refrigerator is based on the physical phenomenon of condensation and evaporation, which is expressed in the following: the heat pump of the refrigeration unit transfers heat energy from the working chamber to the outside, where it cools and dissipates into the external environment. Cooling gas, which is freon, SF6 gas or ammonia, performs the reverse process, as a result of which the cold is produced.

In order to achieve high cooling capacity, a large area of the heating and cooling heat exchanger is needed so that a high pressure can be created . In modern refrigeration systems, this is not always convenient, so here to achieve the necessary pressure, compressors are used that compress and pump refrigerant vapor, as a result of which not only the pressure but also the temperature of the coolant rises. Thus, the principle of the refrigeration system is based on the elementary laws of physics.

Refrigeration compressors are of the following types:

- screw;

- piston;

- centrifugal type.

The latter are the most effective and have found wide application in modern industrial refrigerating plants. In addition, in any refrigerator and freezer necessarily includes a condenser, which is designed to convert vapors into liquid due to changes in ambient temperature.

In general, the principle of the refrigerator is used not only to create refrigerators for various purposes, but also freezing systems, because by adjusting the pressure in the system it is possible to obtain the necessary temperature of the internal environment of the chamber. When the compressor is operating, the refrigerant passes under high pressure through special throttling openings and enters the evaporator chamber, where as a result of a sharp decrease in pressure, the liquid instantly turns into steam. In this physical phenomenon, the refrigerant, due to its properties, takes away heat from the walls of the evaporator, resulting in gradual cooling of the inner chamber of the refrigeration system.

The principle of the refrigerator has been used for 100 years, with new and improved installations every year. One of the latest inventions in this field was the emergence of thermoelectric refrigeration plants, in which the Peltier principle is used. The effect is based on the appearance of a difference in the temperature environment during the flow of current, as a result of which it is possible to achieve a decrease in the temperature of the internal environment of the refrigerating space. Despite the fact that this scientist discovered this property of electric current quite long time ago, until such time, such refrigerating chambers were not received. Usually they were used in automotive coolers, potable water coolers and refrigerator bags, however, due to the high cost of the thermoelectric cooling elements, until recently they were not quite common.

The modern operating principle of the refrigerator will allow the use of industrial refrigerating and freezing units in the food industry, as well as in cold stores and warehouses. It is difficult to overestimate the significance of the discovery of the second law of thermodynamics, since without it it would be impossible to carry out all the activities of modern food processing plants. Thus, the operating principle of the refrigerator is now the basis for all modern cooling installations for both industrial and domestic purposes.