Refrigerator can be divided into: compression refrigera […]
Refrigerator can be divided into: compression refrigerator, absorption refrigerator, steam jet refrigerator, semiconductor refrigeration. Among them, steam compression refrigerator (piston type, rotary type, screw type, centrifugal type), absorption refrigerator and steam jet refrigerator are widely used. At present, in China, except for a few refrigerators with large cooling capacity and special purpose, the general-purpose piston type, centrifugal type, screw type, scroll type, lithium bromide absorption type, steam jet type refrigerators, as well as refrigeration, refrigeration, low temperature test and other equipment can be manufactured by themselves.
The main features of various types of refrigerators are as follows:
1. Compression refrigeration
1) Screw chiller: simple structure, less vulnerable parts, long service life, high single-stage compression ratio, in the range of large and medium-sized refrigeration capacity has the trend of replacing piston type.
2) Piston refrigerator: it has mature technology development, high efficiency and wide range of use temperature. It can be made into large, medium and small products of various specifications. It is the most widely used type of refrigerator.
3) Centrifugal chiller: it uses the high-speed rotating impeller to obtain the kinetic energy of refrigerant gas, and then increases its pressure through the diffuser, cools and liquefies, throttles and refrigerates. The utility model has the advantages of compact structure, large refrigerating capacity of a single machine and energy regulation. R11 and R12 refrigerants are mostly used in air conditioning machines.
2. Absorption refrigeration
The refrigerant is evaporated and cooled by the absorption of absorbent. Commonly used are ammonia water absorption chiller and lithium bromide water absorption chiller. They use heat source as power, consume less power, operate stably, wear less parts, and have a wide range of energy regulation. They are a new type of developed chiller.
A machine that transfers the heat of a cooled object with a lower temperature to an environmental medium to obtain cooling capacity. The heat transferred from a lower temperature object is conventionally called cooling capacity. Refrigerants are the refrigerants that participate in the change of thermal process (energy conversion and heat transfer). The temperature range of refrigeration is usually above 120K, and below 120K belongs to the range of deep and low temperature technology. Refrigerators are widely used in industrial and agricultural production and daily life.