Cold room refrigeration equipment: refrigeration compressor, condenser, expansion valve, evaporator.
Principle of the refrigeration cycle: when the refrigerant is in the state of low-temperature and low-pressure liquid, the heat absorption reaches the boiling point and then evaporates into low-temperature and low-pressure steam. The refrigerant evaporated into gas becomes high-temperature and high-pressure gas under the action of the compressor. This high-temperature and the high-pressure liquid become high-pressure liquid after condensation. The high-pressure liquid turns into a low-pressure and low-temperature liquid through the expansion valve, and the heat absorption evaporation again constitutes the refrigeration cycle of the refrigerator.
Basic concepts and principles
Refrigeration capacity: under certain operating conditions (i.e. certain refrigerant evaporation temperature, condensation temperature, subcooling temperature), the heat of refrigerant taken out from the frozen substance per unit time. Also known as refrigerant cooling capacity. Under the same conditions, the refrigeration capacity of the same refrigerant is related to the size, speed, and efficiency of the compressor.
Direct refrigeration: in the refrigeration cycle, if the evaporator that the refrigerant absorbs heat directly exchanges heat with the surrounding environment of the object being cooled or the object being cooled. Generally, it is used in single refrigeration equipment that needs working cooling, such as ice cream freezer, small refrigerator, and a household refrigerator.
Refrigerant: the working substance that circulates continuously in the refrigeration device to realize refrigeration. The vapor compression refrigeration device realizes the heat transfer through the change of refrigerant state. Refrigerant is an indispensable material to realize artificial refrigeration.
Indirect refrigeration: using cheap materials as the medium carrier to realize the heat exchange between the refrigeration device and the cooling place or machine. Principle of indirect evaporative refrigeration: after the refrigerant is absorbed from the refrigerant in the evaporator, the refrigerant enters the cold storage through the brine pump, exchanges heat with the cooled object or the medium in the workplace, absorbs heat, returns to the evaporator again, transfers the absorbed heat to the refrigerant, and re conducts the cooling cycle.
Refrigerant: the cooling capacity generated by putting the refrigerant in the refrigeration device into the evaporator is transferred to the object to be cooled, the heat absorbed is transferred to the refrigeration device and then transferred to the refrigerant, which is used for cooling again.