Development of refrigeration equipment

Refrigeration equipment refers to the equipment mainly used for crew food refrigeration, all kinds of cargo refrigeration and cabin air conditioning in summer. It is mainly composed of compressor expansion valve, evaporator, condenser, accessories and pipelines. According to the working principle, it can be divided into compression refrigeration equipment, absorption refrigeration equipment, steam jet refrigeration equipment, heat pump refrigeration equipment and electric refrigeration equipment. Compression refrigeration equipment is the most widely used in ships. The heat of the object and its surroundings is removed through the working cycle of the equipment, causing and maintaining a certain low temperature state. The refrigerants used are mainly freon and ammonia, especially freon. However, due to the destruction of Freon on the atmospheric ozone layer, it has begun to be restricted by environmental regulations. Ammonia and other new refrigerants are being re used and trial produced. Refrigeration equipment is a device that combines a refrigerator with facilities that use cooling capacity. The refrigeration device is designed and built to effectively use the cooling capacity to refrigerate food or other items; Conduct product performance test and scientific research test at low temperature; In industrial production, some cooling processes or air conditioning can be realized. When objects are cooled or frozen, a certain amount of heat will be released, and the enclosure of the refrigeration device will also transfer a certain amount of heat when it is used. Therefore, in order to maintain the low temperature conditions in the refrigeration device, it is necessary to install a refrigerator to continuously remove these heat, or use the melting of ice or the sublimation of dry ice to absorb these heat.

Refrigeration equipment is a device that combines a refrigerator with facilities that use cooling capacity. The refrigeration device is designed and built to effectively use the cooling capacity to refrigerate food or other items; Conduct product performance test and scientific research test at low temperature; In industrial production, some cooling processes or air conditioning can be realized. When objects are cooled or frozen, a certain amount of heat will be released, and the enclosure of the refrigeration device will also transfer a certain amount of heat when it is used. Therefore, in order to maintain the low temperature conditions in the refrigeration device, it is necessary to install a refrigerator to continuously remove these heat, or use the melting of ice or the sublimation of dry ice to absorb these heat.

Development and History

Before the development of artificial refrigeration, people had known to use natural ice and snow to maintain low temperature conditions in simple equipment, that is, to use natural cold sources. In China, natural ice was used to preserve food about 3000 years ago. In the Book of Songs in the seventh century BC, there were poems about collecting, storing and freezing food with natural ice. Until modern times, people are still using ice, snow, groundwater and other natural cold sources. Refrigeration devices cooled with natural ice or artificial ice can only reach a limited low temperature, and the technical and sanitary conditions are poor, which is difficult to meet various requirements. Modern refrigeration devices all use refrigerators to cool. In 1834, J. Perkins of the United States successfully developed a human powered continuous working refrigerator using ether as the working medium.

In 1844, J Gori has developed a refrigerator with air as working medium, which is used to make ice and cool air in hospitals. From 1872 to 1874, D. Bell and C Von Linde invented ammonia compressor in the United States and Germany respectively, and made ammonia vapor compression refrigerator, which is the beginning of modern compression refrigerator. In the 1850s, the Carles brothers of France successively developed the absorption chillers with sulfuric acid and water as working fluids and ammonia water absorption chillers. In 1910, steam jet refrigerator appeared. Freon refrigerant appeared in 1930, which promoted the rapid development of compression refrigerator. In 1945, the United States successfully developed the silver bromide absorption chiller.