Cascade Refrigeration System with Variable Flow Single Working Substance Parallel Condenser and Evaporator

Abstract

The invention discloses a cascaded refrigeration system in which a variable flow single working substance is connected in parallel with a condenser and an evaporator. Each refrigeration compressor unit of the present invention is made up of refrigeration compressor and four solenoid valves, condenser, evaporator, and the discharge end of each refrigeration compressor is respectively connected with first solenoid valve and second solenoid valve, and each refrigeration compressor The suction end of the machine is respectively connected with the third solenoid valve and the fourth solenoid valve, the first solenoid valve connected to each refrigeration compressor is connected with the inlet of the condenser, and the outlet of each condenser is connected in parallel and passes through the high-temperature throttling valve It is connected to the inlet of the evaporating side of the condensing evaporator. The second solenoid valve connected to each refrigeration compressor is connected in parallel to the inlet of the condensing evaporator. The third solenoid valve connected to each refrigerating compressor is connected in parallel to the evaporation side of the condensing evaporator. The outlet connection, the fourth electromagnetic valve connected to each refrigeration compressor is connected to the outlet of the evaporator, and the inlet of each evaporator is connected in parallel to the outlet of the condensing side of the condensing evaporator through a low-temperature throttling valve. The cascade refrigerating system of the invention is composed of a single working medium, without expansion vessels and other devices, and the system structure is simple.

Description

technical field [0001] The invention relates to a refrigeration unit, more specifically, to a multi-head cascade refrigeration cycle system, which is used to improve the efficiency of the cascade refrigeration system and to regulate the refrigerant flow rate of the refrigeration system. Background technique [0002] The single-stage compression refrigeration system is not suitable for low-temperature refrigeration systems with a compression ratio (the ratio of the discharge pressure to the suction pressure) greater than 12 due to the limitation of the suction and discharge compression ratio of the compressor. In the prior art, when the compression ratio is greater than 12, a two-stage compression refrigeration system is usually used. The two-stage compression refrigeration unit can be driven by a motor, or it can be realized by combining multiple heads. However, the high and low pressure of these two methods are interoperable, and the oil return problem of the compressor is...

AI Technical Summary

Problems solved by technology

However, since the cryogenic working medium is in a supercritical state at room temperature, an expansion vessel is usually installed in the low-temperature refrigeration system, the system is complicated and it is difficult to realize variable working medium flow control

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