A mixed working medium refrigeration system and control method for rapid start-up of a low-temperature preservation box

Abstract

The invention discloses a mixed working medium refrigeration system and a control method for rapid start-up of a low-temperature preservation box. The system includes a compressor, a condenser, a regenerator, a temperature sensor, a two-position three-way solenoid valve, a short capillary, and a one-way valve. , evaporator and long capillary tube; the system realizes switching between start-up mode and refrigeration mode by configuring two-position three-way solenoid valve and one-way valve; when the system is in start-up mode, two-position three-way solenoid valve supplies liquid to short capillary tube, The flow rate of the mixed working fluid entering the regenerator is increased, so that the outlet temperature of the regenerator drops rapidly, so the high boiling point components in the system are gradually condensed, which greatly reduces the high pressure side pressure at the start-up stage; when the system is in cooling mode, the two The position three-way solenoid valve supplies liquid to the long capillary tube and the evaporator, so that the low-boiling components in the system are gradually condensed, thereby further reducing the refrigeration temperature; the invention also provides a control method for the system, which effectively realizes the rapid start-up and cooling of the cryogenic storage box. Reliable and efficient continuous operation.

Description

technical field [0001] The invention belongs to the technical field of refrigeration and low temperature, and in particular relates to a mixed working medium refrigeration system and a control method applied to the quick start of a low temperature preservation box (refrigerator or freezer, etc.). Background technique [0002] In recent years, scholars have carried out a lot of research on the application of non-azeotropic mixed refrigerants in low-temperature refrigeration systems. There is a temperature glide in the process of condensation and evaporation of mixed refrigerants, and Lorentzian can be realized in traditional vapor compression refrigeration systems. Circulation, the temperature glide of the working fluid during the condensation and evaporation process reduces the heat transfer temperature difference and reduces the irreversible loss, so it is beneficial to the improvement of system performance. The throttling refrigeration system using mixed working fluid has ...

AI Technical Summary

Problems solved by technology

[0003] However, the mixed working fluid throttling refrigeration system has the problem of high exhaust pressure and difficulty in starting the system at the initial stage of start-up

This is because at the initial stage of the start-up of the refrigeration system, the overall refrigeration temperature of the system is high, and the mixed working fluid cannot be condensed normally in the condenser, which will cause the pressure on the high-pressure side of the system to rise continuously. When the pressure on the high-pressure side exceeds the limit value, it will cause the pipe Road breaks and causes serious accident

The existing technology usually uses expansion vessels to store excess working fluid, but this also brings disadvantages such as complex systems and large volumes

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