JP6585830B2 - Wave rotor type automatic cascade refrigeration system and operation method thereof - Google Patents

Description

  The present invention belongs to the field of mechanical refrigeration, and relates to a phase change wave rotor automatic cascade refrigeration system and an operation method thereof.

  With the rapid development of the national economy, the demand for lower temperatures is increasing. When producing the current relatively low temperatures, the single stage vapor compression refrigeration cycle cannot already meet the requirements, and the cascade refrigeration cycle is already widely applied. However, the conventional cascade refrigeration system has a complicated system structure with an increase in the number of cascade stages, resulting in an increase in cost. Compared to the conventional cascade refrigeration system, the automatic cascade system has advantages such as a simple structure as a special cascade system, high reliability, and low cost. However, the simple mixing before compression of the high-temperature refrigerant and low-temperature refrigerant in the automatic cascade system cannot produce a sufficient low-temperature pressure increase effect, so the pressure ratio of the single stage compressor is too large, the exhaust temperature is too high, Problems such as reduced refrigeration performance occur.

  Using a phase change wave rotor booster based on unsteady pressure increasing characteristics, its efficiency is higher than the pressure increasing efficiency of the conventional stable pressure increasing process. This technology eliminates the need for components such as pistons or vanes, completes direct energy exchange between high and low pressure fluids with high efficiency only through generated motion shock waves, effectively lowering the pressure ratio of the compressor, Performance can be improved. Cascading the pressure increasing mechanism of the core equipment disclosed in Patent Literature 1, Patent Literature 2, Patent Literature 3 and Patent Literature 4 with an automatic cascade refrigeration system constitutes the main concept of the present invention.

Chinese Patent No. CN102606547A Chinese Patent No. CN102606548A Chinese Patent No. CN103206801A Chinese Patent No. CN103206800A

  The simple mixing of the high-temperature refrigerant and low-temperature refrigerant before compression in the automatic cascade system cannot produce a sufficient low-temperature pressure increase effect, so the pressure ratio of the single stage compressor is too large, the exhaust temperature is too high, and the refrigeration performance This causes problems such as lowering.

  Therefore, in order to solve the problems existing in the prior art, the present invention introduces a phase change wave rotor booster in an automatic cascade refrigeration cycle apparatus and uses the characteristics of the phase change wave rotor booster to increase the temperature and increase the temperature in advance. It is an object of the present invention to provide a phase change wave rotor automatic cascade refrigeration system that achieves the purpose of pressure and its operating method.

  The technical solution used by the present invention is a phase change wave rotor automatic cascade refrigeration system, including an automatic cascade refrigeration device and a pressure booster, the automatic cascade refrigeration device including a condenser, a high-temperature throttle valve, A condensing gas pump, a low-temperature throttle valve, and an evaporator; and the automatic cascade refrigeration apparatus further includes an automatic cascade subcooler, wherein the automatic cascade subcooler exchanges heat between the high-temperature refrigerant and the low-temperature refrigerant and discharges non-condensable gas. The pressure increasing device comprises a phase change wave rotor booster and a steam compressor, the medium pressure steam outlet of the phase change wave rotor booster is connected to the inlet of the steam compressor, and the outlet of the steam compressor is the inlet of the condenser And the outlet of the condenser is divided into two paths, one path of the automatic cascade subcooler The hot-side outlet of the automatic cascade subcooler is connected to the inlet of the low-temperature throttle valve, the outlet of the low-temperature throttle valve is connected to the cold-side inlet of the evaporator, and the cold-side outlet of the evaporator is Connected to the low pressure steam inlet of the change wave rotor booster; the other path is connected to the inlet of the hot throttle valve, the outlet of the hot throttle valve is connected to the cold side inlet of the automatic cascade subcooler, and the cold of the automatic cascade subcooler The side outlet connects to the drive steam inlet of the phase change wave rotor booster; the non-condensable gas outlet of the autocascade subcooler connects to the non-condensable gas pump; the evaporator hot side inlet and outlet are likewise the cooling medium line Connected with.

A method of operating a phase change wave rotor automatic cascade refrigeration system, using the following steps.
High pressure steam blown into the driving steam inlet of the phase change wave rotor booster and blown into the low pressure steam inlet of the phase change wave rotor booster through the isentropic expansion process. Mixing and discharging from the pressure-increasing steam outlet, entering the steam compressor, compressing as high-temperature and high-pressure superheated steam, passing through the condenser, then two paths of low-temperature refrigerant and high-temperature refrigerant in the form of high-pressure saturated liquid The low-temperature refrigerant is discharged into the supercooled liquid by discharging the non-condensable gas through the automatic cascade sub-cooler, and the temperature is lowered to the set temperature through the low-temperature throttle valve, and is supplied to the evaporator in the form of a low-temperature and low-pressure gas-liquid mixture. And endothermic constant pressure and converted to low-pressure saturated steam to complete the refrigeration cycle, then low-pressure steam of phase change wave rotor booster Next; high-temperature refrigerant, after cooling step down through the hot throttle valve, the refrigerant absorbs heat by blowing the autocascade subcooler, the motive steam phase change wave rotor booster in the form of high temperature and high pressure steam.

1. The driving steam of the phase change wave rotor booster is provided by the residual heat of the automatic cascade system, achieving the purpose of energy saving and environmental conservation.
2. The unsteady pressure increase characteristic of the phase change wave rotor booster effectively lowers the pressure ratio of the steam compressor, and has the effect of increasing the temperature and increasing pressure in advance.
3. The phase change wave rotor booster has not only the pressure-increasing property, but also has excellent liquid handling operability, small structural dimensions, low rotation speed, and easy development of equipment.
4. The use of an automatic cascade subcooler can greatly simplify the structure of the automatic cascade system and reduce the cost.

Phase change wave rotor automatic cascade refrigeration system circuit diagram Ph graph of phase change wave rotor automatic cascade refrigeration system

  Hereinafter, the present invention will be described in detail by combining examples and the accompanying drawings.

Phase change wave rotor automatic cascade refrigeration system using mixed refrigerant:
FIG. 1 is a phase change wave rotor automatic cascade refrigeration system for mixed refrigerants. The mixed refrigerant phase change wave rotor automatic cascade refrigeration system in the figure includes an automatic cascade refrigeration apparatus and a pressure booster. The automatic cascade refrigeration apparatus includes a condenser 3, a high temperature throttle valve 4, a non-condensing gas pump 5, a low temperature throttle valve 7, an evaporator 8, and an automatic cascade subcooler 6. The refrigerant exchanges heat and discharges non-condensable gas. The pressure-increasing device comprises a phase change wave rotor booster 1 and a steam compressor 2, and the medium pressure steam outlet Mp of the phase change wave rotor booster 1 is connected to the inlet of the steam compressor 2. The outlet is connected to the inlet of the condenser 3, the outlet of the condenser 3 is divided into two paths, one path is connected to the hot side inlet of the automatic cascade subcooler 6, and the hot side outlet of the automatic cascade subcooler 6 is connected Connected to the inlet of the low temperature throttle valve 7, the outlet of the low temperature throttle valve 7 connected to the cold side inlet of the evaporator 8, and the cold side outlet of the evaporator 8 connected to the low pressure steam inlet Lp of the phase change wave rotor booster 1. Another path connects to the inlet of the hot throttle valve 4 and the outlet of the hot throttle valve 4 connects to the cold side inlet of the automatic cascade subcooler 6; The cold side outlet of the dynamic cascade subcooler 6 is connected to the driving steam inlet Hp of the phase change wave rotor booster 1; the noncondensable gas outlet of the automatic cascade subcooler 6 is connected to the noncondensable gas pump 5; The side inlet and outlet are likewise connected by a cooling medium line.

  Medium pressure steam is blown into the driving steam inlet Hp of the phase change wave rotor booster 1 and blown into the low pressure steam inlet Lp of the phase change wave rotor booster 1 through the isentropic expansion process and low pressure saturated steam through quasi-isentropic compression. Are mixed at the same pressure and discharged from the pressure-increasing steam outlet Mp, and then enter the steam compressor 2 to be compressed as high-temperature and high-pressure superheated steam. After passing through the condenser 3, low-temperature refrigerant in the form of high-pressure saturated liquid The low-temperature refrigerant is discharged from the non-condensable gas through the automatic cascade subcooler 6 and cooled down to become a supercooled liquid. After entering the evaporator 8 in the form of a gas-liquid mixture, endothermic constant pressure and converted into low-pressure saturated steam to complete the refrigeration cycle, then the phase change way The low-pressure steam of the rotor booster 1 is obtained; after the temperature of the high-temperature refrigerant is lowered and lowered through the high-temperature throttle valve 4, the high-temperature refrigerant is blown into the automatic cascade subcooler 6 to absorb heat and become the driving steam of the phase change wave rotor booster 1 in the form of high-temperature high-pressure steam. .

  FIG. 2 is a ph diagram of a mixed refrigerant phase change wave rotor automatic cascade refrigeration system. As can be seen from the figure, the high pressure superheated steam at point Fa that is isentropically expanded to Fa ′ in the phase change wave rotor booster 1 and the low pressure saturation at point A that is isentropically compressed to point A ′ in the phase change wave rotor booster 1. When steam is mixed to point B at the same pressure and the superheated steam at point B is compressed by the steam compressor 2, it becomes high-temperature and high-pressure superheated steam at point C. The high-pressure saturated liquid at point D is divided into two paths, a low-temperature refrigerant and a high-temperature refrigerant, and the low-temperature refrigerant is heat-exchanged by the automatic cascade subcooler 6 to cool down to become a high-pressure supercooled liquid at point G. The non-condensable gas is discharged by the condensing gas pump 5, the enthalpy temperature is lowered by the low-temperature throttle valve 7, and the pressure is reduced to the low-pressure supersaturated steam at the point H. The temperature rises to low pressure saturated steam at point A to complete the refrigeration cycle, and is blown into the low pressure steam inlet Lp of the phase change wave rotor booster 1; The high-pressure supersaturated steam is exchanged by the automatic cascade subcooler 6, and the temperature is raised and the high-pressure superheated and steamed state at point Fa is reached and blown into the driving steam inlet Hp of the phase change wave rotor booster 1.

Multistage vapor compression refrigeration system using a single refrigerant:
In principle, the flow and the arrangement of equipment are not changed, and the mixed refrigerant can be changed to a single refrigerant to realize a multi-stage vapor compression refrigeration system using a single refrigerant.

  High pressure supersaturated steam at point Fb that is isentropically expanded to Fb ′ in the phase change wave rotor booster 1 and low pressure saturated steam at point A that is isentropically compressed to point A ′ in the phase change wave rotor booster 1 are isobaric to point B. When the superheated steam at point B is compressed by the steam compressor 2, it becomes high-temperature and high-pressure superheated steam at point C, and is cooled at a constant pressure by the condenser 3 to become a high-pressure saturated liquid at point D. The saturated liquid is divided into two paths, a low-temperature refrigerant and a high-temperature refrigerant. The low-temperature refrigerant exchanges heat by the automatic cascade subcooler 6 and cools down to become a high-pressure supercooled liquid at point G. The enthalpy temperature is lowered and lowered by the low-temperature throttle valve 7 to become a low-pressure supersaturated steam at point H, the heat is exchanged by the evaporator 8 and the temperature is raised to low-pressure saturated at point A. Completes the refrigeration cycle with Japanese steam and blows into the low-pressure steam inlet Lp of the phase change wave rotor booster 1; the high-temperature refrigerant is cooled down to enthalpy by the high-temperature throttle valve 4 and is reduced to E high-pressure supersaturated steam. The heat is exchanged by the cascade subcooler 6 and the temperature is raised to high pressure supersaturation and a steam state at the point Fa, and blown into the driving steam inlet Hp of the phase change wave rotor booster 1.

  The driving steam of the phase change wave rotor booster is provided by the residual heat of the automatic cascade system, achieving the purpose of energy saving and environmental protection; Reduced ratio, increased low temperature, pre-pressurized effect; phase change wave rotor booster has not only the pressure-increasing property, but also excellent liquid handling operability, small structure size and low rotation speed It has advantages such as easy development of equipment. The use of an automatic cascade subcooler can greatly simplify the structure of the automatic cascade system and reduce costs.

DESCRIPTION OF SYMBOLS 1 Phase change wave rotor booster 2 Steam compressor 3 Condenser 4 High-temperature throttle valve 5 Non-condensable gas pump 6 Automatic cascade subcooler 7 Low-temperature throttle valve 8 Evaporator HP drive steam inlet LP Low-pressure steam inlet MP Boosting steam outlet

Claims (2)

A wave including an automatic cascade refrigeration apparatus including a condenser (3), a high temperature throttle valve (4), a non-condensing gas pump (5), a low temperature throttle valve (7), and an evaporator (8), and a pressure increasing device A rotor type automatic cascade refrigeration system,
The automatic cascade refrigeration system further comprises an automatic cascade subcooler (6), said automatic cascade subcooler (6) is discharged noncondensable gas hot refrigerant and the low-temperature refrigerant causes heat exchange, the pressure increasing device is increased air equipped wave low data is pressure means (1) and vapor compressor (2), said steam outlet in the wave row data (1) (Mp) is connected to an inlet of the vapor compressor (2), The outlet of the vapor compressor (2) is connected to the inlet of the condenser (3), the outlet of the condenser (3) is divided into two paths, one path of the automatic cascade subcooler (6). A hot side inlet is connected, a hot side outlet of the automatic cascade subcooler (6) is connected to an inlet of the low temperature throttle valve (7), and an outlet of the low temperature throttle valve (7) is connected to the evaporator (8). Co Connected to the de-side inlet, the low-pressure connecting steam inlet and (Lp) of the cold side outlet is the wave low motor (1) of the evaporator (8); a path different from the inlet of the hot throttle valve (4) connected to the outlet of the hot throttle valve (4) is connected to the cold side inlet of the autocascade subcooler (6), wherein the cold side outlet of the autocascade subcooler (6) is the wave low motor (1) The non-condensable gas outlet of the automatic cascade subcooler (6) is connected to the non-condensable gas pump (5); the hot side inlet and outlet of the evaporator (8) Similarly, a wave rotor type automatic cascade refrigeration system, which is connected by a cooling medium pipe. An operation method of the wave rotor type automatic cascade refrigeration system according to claim 1,
Blowing high-temperature high-pressure steam to the wave low motor (1) driving the steam inlet (Hp), blowing low pressure saturated steam to a low pressure steam inlet of the wave row data (1) (Lp), and mixing the two, and increasing steam outlet (Mp), and enters the vapor compressor (2) to be compressed as high-temperature and high-pressure superheated steam, and after passing through the condenser (3), the low-temperature refrigerant and the high-temperature refrigerant in the form of a high-pressure saturated liquid. The low-temperature refrigerant is discharged from the non-condensable gas through the automatic cascade subcooler (6) and cooled down to become a supercooled liquid, and the low-temperature refrigerant is cooled down to the set temperature through the low-temperature throttle valve (7). in the form of a mixture enters the evaporator (8), the refrigerant absorbs heat pressure becomes low-pressure steam wave low motor (1) from to complete the refrigeration cycle is converted into a low-pressure saturated steam; hot refrigerant, hot throttle Bas After the step-down cooling through blanking (4), the operation method by blowing the autocascade subcooler (6) absorbs heat, characterized in that the motive steam wave low motor (1) in the form of high temperature and high pressure steam.

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