CN117628726A - Multistage air supplementing injection type high-temperature heat pump system, control method thereof and heat exchange system - Google Patents

Abstract

The invention relates to the technical field of heat pump energy conservation, in particular to a multi-stage air supplementing injection type high-temperature heat pump system, a control method thereof and a heat exchange system, wherein the heat pump system comprises a multi-stage air supplementing compressor, a first liquid separating condenser, a first throttle valve, a flash tank, a first injector, a second throttle valve and a gas separating evaporator; the outlet of the multi-stage air supplementing compressor is communicated with the inlet of the first liquid separating condenser; one outlet of the first liquid separation condenser is communicated with the inlet of the flash tank through a first throttle valve, and the other outlet of the first liquid separation condenser is communicated with the inlet of the gas separation evaporator through a second throttle valve; one outlet of the flash tank, one outlet of the first ejector and one outlet of the split-gas evaporator are respectively communicated with different inlets of the multi-stage air supplementing compressor; the other outlet of the flash tank is communicated with one inlet of the first ejector; the other outlet of the gas-dividing evaporator is communicated with the other inlet of the first ejector. The invention can greatly reduce irreversible loss in the heat exchange process and obviously improve the energy utilization efficiency.

Description

Multistage air supplementing injection type high-temperature heat pump system, control method thereof and heat exchange system

Technical Field

The invention relates to the technical field of heat pump energy conservation, in particular to a multi-stage air supplementing injection type high-temperature heat pump system, a control method thereof and a heat exchange system.

Background

The heat pump system is widely applied to the aspects of waste heat recovery, space heating, hot water preparation and the like as an efficient and environment-friendly technology. In order to further improve the application range of the heat pump system, the application scene and the temperature rise requirement of the heat pump are more complex, and the high-temperature heat pump system with large temperature rise accords with the development trend of the heat pump technology to a higher temperature area, can also utilize lower-grade heat energy, and is a low-carbon energy-saving technology which accords with the background of the current age.

The non-azeotropic working medium is applied to a heat pump system, so that the characteristic that the non-azeotropic working medium has temperature slippage in the phase change process can be utilized, the average heat exchange temperature difference is reduced, and the energy efficiency is improved. However, under the complicated heat utilization condition, the components of the non-azeotropic working medium are fixed, the temperature slippage is unchanged, and the adjustment can not be carried out according to the heat utilization requirement, so that the heat transfer effect is deteriorated. In the condensation process, the working medium is changed from a gas phase to a liquid phase, and the thickness of a liquid film is continuously increased along with the reduction of dryness, so that the heat transfer efficiency is reduced; in the evaporation process, the heat transfer coefficient of the working medium has obvious fluctuation along with the increasing trend of dryness. Therefore, how to expand the applicable temperature range of the heat pump system, reduce the irreversible loss in the heat exchange process, and improve the performance of the heat pump system is a main direction of research by those skilled in the art.

Disclosure of Invention

The invention aims to overcome the defects of the prior art, and provides a multistage air supplementing injection type high-temperature heat pump system which adopts a sectional heat exchange matching mode, so that the irreversible loss in the heat exchange process can be greatly reduced, and the energy utilization efficiency is remarkably improved.

In order to solve the technical problems, the invention adopts the following technical scheme:

the multi-stage air supplementing jet type high-temperature heat pump system comprises a multi-stage air supplementing compressor, a first liquid separating condenser, a first throttle valve, a flash tank, a first ejector, a second throttle valve and a gas separating evaporator;

the outlet of the multistage air compressor is communicated with the inlet of the first liquid separating condenser; one outlet of the first split liquid condenser is communicated with the inlet of the flash tank through a first throttle valve, and the other outlet of the first split liquid condenser is communicated with the inlet of the split evaporator through a second throttle valve; one of the outlets of the flash tank, the outlet of the first ejector and one of the outlets of the gas-dividing evaporator are respectively communicated with different inlets of the multi-stage air-supplementing compressor; the other outlet of the flash tank is communicated with one inlet of the first ejector; the other outlet of the gas-dividing evaporator is communicated with the other inlet of the first ejector.

According to the multistage air supplementing injection type high-temperature heat pump system, irreversible heat exchange loss is reduced by utilizing the temperature sliding characteristic of the non-azeotropic working medium; component regulation and control inside the heat exchanger are realized through the liquid separation condenser and the gas separation evaporator, and global regulation and control of working medium components of the thermodynamic system are realized through the ejector and the flash tank. By changing the components of the working medium, the temperature slippage of the working medium is regulated, so that better heat exchange matching is realized, and the system efficiency is improved. In addition, the ejector can save the power consumption in the compression process, the multistage compression middle air supplementing can realize the middle cooling in the compression process, the exhaust temperature of the compressor is effectively reduced, and the running performance of the system is improved. For the heat exchange process, gas-liquid separation exists in the split liquid evaporator and the split gas evaporator, so that the dryness of the heat exchange process can be regulated and controlled, and a higher heat transfer coefficient is maintained, so that the heat exchange quantity of the heat exchanger is improved. The first, second, third, etc. are used herein only to distinguish between components that are located at different positions, e.g., the first throttle valve and the second throttle valve are each representative of a throttle valve, and are merely located differently, and may be identical in structure and function.

Preferably, the inlet of the multi-stage air supplementing compressor at least comprises a multi-stage air supplementing compressor inlet, a first air supplementing port and a second air supplementing port, the outlet of the first ejector is communicated with the first air supplementing port, and one outlet of the flash tank is communicated with the second air supplementing port.

Preferably, the system further comprises a high-pressure evaporator, and the outlet of the first ejector is communicated with the first air supplementing port through the high-pressure evaporator.

Preferably, the system further comprises a second liquid-separating condenser, a second ejector, a third throttle valve and a high-pressure compressor, wherein the outlet of the multi-stage air-supplementing compressor is divided into two paths, one path is communicated with the inlet of the first liquid-separating condenser through the high-pressure compressor, and the other path of the outlet of the multi-stage air-supplementing compressor is communicated with the inlet of the second liquid-separating condenser through the second ejector; one outlet of the second liquid-separating condenser is communicated with the inlet of the flash tank through the first throttle valve, and the other outlet of the second liquid-separating condenser is communicated with the inlet of the gas-separating evaporator through the third throttle valve. For the heat consumption requirement of large temperature rise, the first liquid-separating condenser and the second liquid-separating condenser are utilized for carrying out sectional heat exchange matching, so that the irreversible loss in the heat exchange process can be greatly reduced, and the energy utilization efficiency is obviously improved.

Preferably, the first liquid-separating condenser comprises a condensation header, a plurality of condensation heat exchange pipes, condensation liquid-separating pipes and a liquid-separating partition plate, a plurality of liquid-separating holes are formed in the liquid-separating partition plate in a penetrating mode, the liquid-separating partition plate is arranged in the condensation header, the condensation heat exchange pipes are sequentially arranged and mutually communicated and are communicated with the condensation header, the condensation liquid-separating pipes are also communicated with the condensation header, an inlet of the condensation header is communicated with an outlet of the multi-stage air-supplementing compressor, an outlet of the condensation header is communicated with an inlet of the second throttle valve, and the condensation liquid-separating pipes are communicated with an inlet of the flash tank through the first throttle valve.

Preferably, the gas distributing evaporator comprises an evaporation header, a plurality of evaporation heat exchange pipes, an evaporation gas distributing pipe and an evaporation partition plate, wherein the evaporation partition plate is arranged on the evaporation header, the evaporation heat exchange pipes are sequentially arranged and mutually communicated and are communicated with the evaporation header, the evaporation gas distributing pipe is also communicated with the evaporation header, an inlet of the evaporation header is communicated with an outlet of the second throttle valve, an outlet of the evaporation header is communicated with an inlet of the multi-stage air supplementing compressor, and the evaporation gas distributing pipe is communicated with one inlet of the first ejector.

Preferably, the inlet of the first ejector is divided into an injection inlet and an injected inlet, the injection inlet is communicated with the liquid phase outlet of the flash tank, and the injected inlet is communicated with the gas distributing outlet of the gas distributing evaporator.

Preferably, the working pressure of the injection inlet is greater than the working pressure of the injected inlet.

The invention also provides a heat exchange system which comprises the multi-stage air supplementing jet type high-temperature heat pump system, a heat exchange side heat exchange module and a heat source side heat exchange module, wherein the heat exchange side heat exchange module is sequentially communicated with the second liquid separation condenser and the first liquid separation condenser, and the heat source side heat exchange module is sequentially communicated with the high-pressure evaporator and the gas separation evaporator.

The invention also provides a control method of the multistage air supplementing injection type high-temperature heat pump system, which is applied to the multistage air supplementing injection type high-temperature heat pump system and is operated as follows:

the working pressure of the first liquid separation condenser is defined to be six-level pressure, the working pressure of the second liquid separation condenser and the working pressure of the second ejector are defined to be five-level pressure, the pressure of an outlet of the multi-level air supplementing compressor is four-level pressure, the working pressure of the flash tank is three-level pressure, the working pressure of the first ejector and the working pressure of the high-pressure evaporator are two-level pressure, the working pressure of the air separation evaporator is one-level pressure, and the working pressures of all parts meet the following conditions: six-level pressure > five-level pressure > four-level pressure > three-level pressure > two-level pressure > one-level pressure;

controlling the liquid separation flow of the first liquid separation condenser and the second liquid separation condenser, the gas separation flow of the gas separation evaporator and the branch flow from the multi-stage air supplementing compressor to the second ejector, and enabling the liquid separation flow of the first liquid separation condenser to be smaller than the main path flow of the first liquid separation condenser, the liquid separation flow of the second liquid separation condenser to be smaller than the main path flow of the second liquid separation condenser, the gas separation flow of the gas separation evaporator to be smaller than the main path flow of the gas separation evaporator, and the branch flow from the multi-stage air supplementing compressor to the second ejector to be smaller than the branch flow from the multi-stage air supplementing compressor to the first liquid separation condenser.

Compared with the prior art, the invention has the beneficial effects that:

the invention utilizes the temperature sliding characteristic of non-azeotropic working medium to reduce irreversible loss of heat exchange; component regulation and control inside the heat exchanger are realized through the liquid separation condenser and the gas separation evaporator, and global regulation and control of working medium components of the thermodynamic system are realized through the ejector and the flash tank. By changing the components of the working medium, the temperature slippage of the working medium is regulated, so that better heat exchange matching is realized, and the system efficiency is improved. In addition, the ejector can save the power consumption in the compression process, the multistage compression middle air supplementing can realize the middle cooling in the compression process, the exhaust temperature of the compressor is effectively reduced, and the running performance of the system is improved. For the heat exchange process, because the gas-liquid separation exists in the split liquid evaporator and the split gas evaporator, the dryness of the heat exchange process can be regulated and controlled, and a higher heat transfer coefficient is maintained, so that the heat exchange capacity of the heat exchanger is improved. For the heat consumption requirement of large temperature rise, the method of sectional heat exchange matching is adopted, so that the irreversible loss in the heat exchange process can be greatly reduced, and the energy utilization efficiency is remarkably improved. The system is an improvement scheme with energy conservation, economy, environmental protection and high efficiency, can effectively improve the performance of the heat pump circulation system, promotes the low-carbon energy-saving technology of the heat pump system, and promotes the development of the heat pump technology to a higher temperature area.

Drawings

FIG. 1 is a schematic diagram of a multi-stage air-make-up injection high temperature heat pump system according to example 1 of the present invention;

FIG. 2 is a schematic diagram of a multi-stage air-make-up injection type high temperature heat pump system according to embodiment 3 of the present invention;

FIG. 3 is a schematic diagram of the working medium components of example 3 of a multi-stage air-make-up injection high temperature heat pump system of the present invention;

FIG. 4 is a schematic diagram of a split liquid condenser of a multi-stage air make-up injection high temperature heat pump system according to the present invention;

FIG. 5 is a schematic view of the condensate outlet of the multi-stage air make-up injection high temperature heat pump system according to the present invention;

FIG. 6 is a schematic diagram of a vapor distributor of a multi-stage vapor injection high temperature heat pump system according to the present invention;

FIG. 7 is a schematic view of the structure of the evaporation gas-separating outlet of the multi-stage air-supplementing injection type high-temperature heat pump system of the present invention;

FIG. 8 is a schematic diagram of a multistage air make-up compressor of a multistage air make-up injection type high temperature heat pump system according to the present invention;

FIG. 9 is a schematic diagram of a staged heat exchange match for a multi-stage air make-up injection high temperature heat pump system of the present invention.

The graphic indicia are illustrated as follows:

101. a multi-stage air compressor; 1011. a multi-stage air compressor inlet; 1012. a multi-stage air compressor outlet; 1013. a first air supply port; 1014. a second air supply port; 102. a high pressure compressor; 103. a first split liquid condenser; 1031. condensing the heat exchange tube; 1032. a condensing header; 1033. condensing and separating liquid pipe; 1034. a liquid separation baffle; 1035. a liquid separation hole; 104. a second throttle valve; 105. a third throttle valve; 106. a gas separation evaporator; 1061. evaporating the heat exchange tube; 1062. an evaporation header; 1063. evaporating and distributing pipes; 1064. an evaporation separator; 107. a second ejector; 108. a second liquid separation condenser; 109. a first throttle valve; 110. a flash tank; 111. a first injector; 112. a high pressure evaporator; 113. a heat sink side heat exchange module; 114. a heat source side heat exchange module; a-r represent different positions; x is x ₁ ～x ₁₃ Representing different working fluid components.

Detailed Description

The invention is further described below in connection with the following detailed description. Wherein the drawings are for illustrative purposes only and are shown in schematic, non-physical, and not intended to be limiting of the present patent; for the purpose of better illustrating embodiments of the invention, certain elements of the drawings may be omitted, enlarged or reduced and do not represent the size of the actual product; it will be appreciated by those skilled in the art that certain well-known structures in the drawings and descriptions thereof may be omitted.

In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings are merely for convenience in describing the present invention and simplifying the description, and do not indicate or imply that the device or element being referred to must have a specific orientation, be configured and operated in a specific orientation, and therefore should not be construed as limiting the present invention.

Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include at least one such feature. In the description of the present invention, the meaning of "plurality" means at least two, for example, two, three, etc., unless specifically defined otherwise.

In the present invention, unless explicitly specified and limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; either directly or indirectly, through intermediaries, or both, may be in communication with each other or in interaction with each other, unless expressly defined otherwise. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art according to the specific circumstances.

In the present invention, unless expressly stated or limited otherwise, a first feature "up" or "down" a second feature may be the first and second features in direct contact, or the first and second features in indirect contact via an intervening medium. Moreover, a first feature being "above," "over" and "on" a second feature may be a first feature being directly above or obliquely above the second feature, or simply indicating that the first feature is level higher than the second feature. The first feature being "under", "below" and "beneath" the second feature may be the first feature being directly under or obliquely below the second feature, or simply indicating that the first feature is less level than the second feature.

In the description of the present specification, a description referring to terms "one embodiment," "some embodiments," "examples," "specific examples," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms are not necessarily directed to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, the different embodiments or examples described in this specification and the features of the different embodiments or examples may be combined and combined by those skilled in the art without contradiction.

Example 1

Referring to fig. 1, a first embodiment of a multi-stage air-make-up injection type high temperature heat pump system according to the present invention includes a multi-stage air-make-up compressor 101, a first liquid-separating condenser 103, a first throttle valve 109, a flash tank 110, a first injector 111, a second throttle valve 104, and a gas-separating evaporator 106; the outlet of the multi-stage air compressor 101 is communicated with the inlet of the first liquid separating condenser 103; one outlet of the first split liquid condenser 103 is communicated with an inlet of the flash tank 110 through a first throttle valve 109, and the other outlet of the first split liquid condenser 103 is communicated with an inlet of the split gas evaporator 106 through a second throttle valve 104; one outlet of the flash tank 110 communicates with one of the inlets of the first ejector 111, and one outlet of the split evaporator 106 communicates with the other inlet of the first ejector 111; the other outlet of the flash tank 110 communicates with one inlet of the multi-stage air compressor 101, the outlet of the first ejector 111 communicates with the other inlet of the multi-stage air compressor 101, and the other outlet of the gas-dividing evaporator 106 communicates with the other inlet of the multi-stage air compressor 101, which is different from the two inlets.

The first split condenser 103 has two heat exchange fluids, a working fluid side and a heat sink side. The working medium is a medium substance for realizing the mutual conversion of heat energy and mechanical energy, and the connection relation of the working medium side of the invention is shown in figure 1; the heat exchange side refers to a heat exchange system for carrying out cold and heat exchange with the working medium side and is used for carrying out heat exchange on the split condenser, and the heat exchange system is not shown in fig. 1; the outlet of the working medium side of the first liquid-separating condenser 103 is divided into two paths, and the liquid-separating outlet of one path of the first liquid-separating condenser 103 flows through the first throttle valve 109 and is connected with the inlet of the flash tank 110; the outlet of the other path of first liquid separating evaporator 103 flows through a second throttle valve 104 and is connected with the inlet of a gas separating evaporator 106; the split-gas evaporator 106 has two heat exchange streams, a working fluid side and a heat source side, where the heat source side is similar to the heat sink side referred to above, and also serves as a heat exchange system for heat exchange. The outlet of the working medium side of the gas-dividing evaporator 106 is divided into two paths, one path of gas-dividing evaporator 106 is connected with the ejected inlet of the first ejector 111, and the other path of gas-dividing evaporator 106 is connected with the inlet 1011 of the multi-stage air-filling compressor. The multi-stage compressor outlet 1012 is connected to the inlet of the first split liquid condenser 103. The vapor phase outlet of the flash tank 110 is connected with the second air compensating port 1014 of the multi-stage air compensating compressor 101, the liquid phase outlet of the flash tank 110 is connected with the injection inlet of the first injector 111, and the outlet of the first injector 111 is connected with the first air compensating port 1013 of the multi-stage air compensating compressor 101.

The working medium in the embodiment is a non-azeotropic mixed working medium, and is formed by mixing a working medium with a high boiling point and a working medium with a low boiling point according to a certain proportion. The heat pump system adopts the non-azeotropic working medium to circulate, and the non-azeotropic working medium temperature sliding is matched with the heat exchange process, so that the irreversible loss in the circulation process can be reduced. The invention utilizes the first ejector 111 and the flash tank 110 to realize the global regulation and control of the working medium components of the thermodynamic system, saves the power consumption in the compression process, realizes the intermediate cooling in the compression process, effectively reduces the exhaust temperature of the compressor and improves the operation performance of the system.

As an embodiment of the present invention, the first liquid-splitting condenser 103 includes a condensation header 1032, a plurality of condensation heat exchange tubes 1031, a condensation liquid-splitting tube 1033, and a liquid-splitting partition 1034, wherein a plurality of liquid-splitting holes 1035 are formed in the liquid-splitting partition 1034 in a penetrating manner, the liquid-splitting partition 1034 is installed on the condensation header 1032, the plurality of condensation heat exchange tubes 1031 are sequentially arranged and mutually communicated and are all communicated with the condensation header 1032, the condensation liquid-splitting tube 1033 is also communicated with the condensation header 1032, an inlet of the condensation header 1032 is communicated with the outlet 1012 of the multi-stage air-filling compressor, an outlet of the condensation header 1032 is communicated with an inlet of the second throttle valve 104, and the condensation liquid-splitting tube 1033 is communicated with an inlet of the flash tank 110 through the first throttle valve 109.

The size and the number of the liquid separation holes 1035 on the liquid separation partition 1034 and the pipe diameter of the condensation liquid separation pipe 1033 are reasonably adjusted, so that the components and the flow of the working medium at the liquid separation outlet can be regulated and controlled, the components of the residual working medium in the liquid separation condenser are changed, the thermophysical parameters are changed, the temperature sliding of the liquid separation condenser is regulated and controlled, the irreversible heat exchange loss of the liquid separation condenser is reduced, the dryness of the residual working medium is improved, and the heat exchange capacity of the liquid separation condenser is enhanced.

As an embodiment of the present invention, the split-gas evaporator 106 includes an evaporation header 1062, a plurality of evaporation heat exchange tubes 1061, an evaporation gas-distributing tube 1063, and an evaporation partition 1064, the evaporation partition 1064 is disposed in the evaporation header 1062, the plurality of evaporation heat exchange tubes 1061 are sequentially disposed and communicate with each other and all communicate with the evaporation header 1062, the evaporation gas-distributing tube 1063 is also communicated with the evaporation header 1062, an inlet of the evaporation header 1062 is communicated with an outlet of the second throttle valve 104, an outlet of the evaporation header 1062 is communicated with the multi-stage air-compensating compressor inlet 1011, and the evaporation gas-distributing tube 1063 is communicated with one of the inlets of the first ejectors 111.

The pipe diameter of the evaporation gas distribution pipe 1063 is reasonably designed, so that the components and the flow of the working medium at the evaporation gas distribution outlet can be adjusted, the components of the residual working medium in the gas distribution evaporator 106 are changed, the thermal physical parameters of the working medium are changed, the temperature sliding of the working medium is regulated and controlled, the irreversible loss of heat exchange of the gas distribution evaporator 106 is reduced, the working medium is evaporated under a higher heat transfer coefficient, and the heat exchange efficiency of the gas distribution evaporator 106 is improved.

Example 2

The following is a second embodiment of a multi-stage air-make-up injection high temperature heat pump system according to the present invention, which is similar to embodiment 1, except that it further includes a high pressure evaporator 112, and the outlet of the first ejector 111 is in communication with the first air-make-up port 1013 of the multi-stage air-make-up compressor 101 through the high pressure evaporator 112. The high pressure evaporator 112 is located between the first ejector 111 and the multi-stage air compressor 101. High pressure evaporator 112 has two heat exchange fluids, a working fluid side and a heat source side. The working medium side outlet communicates with the first air supply 1013 of the multi-stage air supply compressor 101. The high-pressure evaporator 112 has several functions, firstly, the gas-liquid two-phase working medium at the outlet of the first ejector 111 can absorb heat and be converted into gas phase, and then the gas phase enters the multi-stage air-supplementing compressor through the first air-supplementing port 1013 of the multi-stage air-supplementing compressor 101, so that the liquid compression in the compression process is avoided, and meanwhile, the exhaust superheat degree of the compressor can be reduced. Second, the evaporator can form dual-temperature (pressure) evaporation with the gas-separation evaporator 106, and the temperature change of the working medium and the heat source is further matched through step heat exchange, so that the temperature change of a larger span is realized. The evaporation process reduces the temperature of the heat source in a gradient way through absorbing heat, so as to realize the temperature reduction to a greater degree.

Example 3

Referring to fig. 2 to 9, a third embodiment of a multi-stage air-make-up injection type high temperature heat pump system according to the present invention is similar to embodiment 2, except that the system further comprises a second liquid-dividing condenser 108, a second ejector 107, a third throttle valve 105, and a high pressure compressor 102, wherein the outlet of the multi-stage air-make-up compressor 101 is divided into two paths, one path is communicated with the inlet of the first liquid-dividing condenser 103 through the high pressure compressor 102, the other path of the outlet of the multi-stage air-make-up compressor 101 is communicated with the inlet of the second liquid-dividing condenser 108 through the second ejector 107, one of the outlets of the second liquid-dividing condenser 108 is communicated with the inlet of the flash tank 110 through the first throttle valve 109, and the other outlet of the second liquid-dividing condenser 108 is communicated with the inlet of the air-dividing evaporator 106 through the third throttle valve 105.

The multi-stage air-supplementing injection high-temperature heat pump system in the embodiment can also be applied to a scene of large temperature rise, the second injector 107 is positioned between and communicated with the first condenser 103 and the second condenser 108, the second injector 107 is also communicated with the outlet 1012 of the multi-stage air-supplementing compressor, and the second liquid-separating condenser 108 has two heat exchange fluids, namely a working medium side and a heat exchange side. The outlet of the working medium side of the second liquid-separating condenser 108 is divided into two paths, wherein the liquid-separating outlet of one path of the second liquid-separating condenser 108 is communicated with the inlet of the flash tank 110 through the first throttle valve 109, and the outlet of the other path of the second liquid-separating condenser 108 is communicated with the inlet of the third throttle valve 105.

The high pressure compressor 102 has the following functions: first, in order to make the working pressures of the first liquid-splitting condenser 103 and the second liquid-splitting condenser 108 inconsistent, the two-temperature (pressure) condensation is also realized, and the temperature change of the working medium and the heat sink is further matched through step heat exchange, so that the temperature change of a larger span is realized. The condensing process causes the temperature of the heat sink to rise in a gradient manner through heat release, so that the temperature rise of a larger degree is realized. Second, the high-pressure compressor 102 cooperates with the first split-liquid condenser 103 and the second ejector 107 to flexibly adjust the components of the circulating working medium.

In this embodiment, the first split liquid condenser 103 includes two outlets, which are a split liquid outlet of the first split liquid condenser 103 and a split liquid condenser 103 outlet, where a saturated liquid phase working medium can be obtained from the split liquid outlet of the first split liquid condenser 103, and the first split liquid condenser 103 outlet is opposite to the inlet of the first split liquid condenser 103, and a supercooled liquid phase working medium exits from the first split liquid condenser 103 outlet, and there may be multiple split liquid outlets of the first split liquid condenser 103, which are added between the inlet of the first split liquid condenser 103 and the outlet of the first split liquid condenser 103; the second liquid-separating condenser 108 has two outlets, namely a liquid-separating outlet of the second liquid-separating condenser 108 and a liquid-separating outlet of the second liquid-separating condenser 108, wherein the liquid-separating outlet of the second liquid-separating condenser 108 and the liquid-separating outlet of the first liquid-separating condenser 103 are arranged in the same way, and the arrangement of the outlet of the second liquid-separating condenser 108 is also similar to the arrangement of the outlet of the first liquid-separating condenser 103. The components and the flow of the working medium are reasonably regulated and controlled, the dryness of the residual working medium is improved, and compared with a common condenser, the condenser has better heat exchange capacity.

Fig. 3 is a schematic diagram of working medium components of a multi-stage air-supplementing injection type high-temperature heat pump system according to an embodiment of the present invention. Wherein the working medium component at the outlet of the gas separation evaporator 106 is x ₁ The working medium component after the multi-stage air supplementing compressor inlet 1011 and the first air supplementing port 1013 are mixed is x ₂ The working medium composition of the outlet 1012 of the multistage air-filling compressor is x ₃ The working medium component at the outlet of the first component liquid condenser 103 is x ₄ The working medium component at the outlet of the third throttle valve 105 is x ₅ The working medium component of the liquid separation outlet of the first liquid separation condenser 103 is x ₆ The working fluid composition at the outlet of the second injector 107 is x ₇ The working medium component at the outlet of the second liquid-splitting condenser 108 is x ₈ The working medium component of the liquid separation outlet of the second liquid separation condenser 108 is x ₉ The working medium component of the vapor phase outlet of the flash tank 110 is x ₁₀ The working fluid composition at the liquid phase outlet of flash tank 110 is x ₁₁ The working medium component of the gas distribution outlet of the gas distribution evaporator 106 is x ₁₂ The working fluid composition at the outlet of the first injector 111 is x ₁₃ . Wherein x is ₁ ～x ₁₃ Respectively representing different working medium components.

As shown in fig. 9, if the heat exchange is performed once and the components of the working medium are not changed, the temperature change of the working medium is equivalent to the outside dotted line, but the temperature change curve of the working medium is changed through gradient heat exchange and the component change in the heat exchange process, the area surrounded by the temperature line of the working medium and the temperature line of the heat sink/source represents the irreversible loss in the heat exchange process, and the larger the area, the larger the irreversible loss, and the lower the system operation efficiency. The line parallel to the heat sink/source temperature line between the working medium temperature line and the heat sink/source temperature line represents the optimal temperature change curve of the working medium under the minimum heat exchange temperature difference, and the area surrounded by the heat sink/source temperature line represents unavoidableLoss is the most ideal heat exchange condition. E (E) _D,pinch It is the unavoidable heat exchange process described above +.>Loss of E _D,fluid Then an avoidable heat exchange process is possible>The sum of the losses is the total +.>Loss. E for different heat exchange processes _D,fluid The smaller, i.e. the better the temperature matching degree of the heat exchange process, +.>The loss is reduced. In conclusion, the +.f. of the heat exchange process can be reduced by gradient heat exchange and component regulation>And loss, and the energy utilization efficiency of the system is improved.

The principle of the invention is as follows: the high-temperature high-pressure gas-phase working medium (point e in the figure) enters the first liquid-separating condenser 103 from the outlet of the high-pressure compressor 102 to be partially condensed, the liquid-phase working medium which is separated from the liquid-separating outlet of the first liquid-separating condenser 103 and is condensed enters the injection inlet (point i in the figure) of the first ejector 111, part of the gas-phase working medium at the outlet 1012 of the multi-stage air-supplementing compressor enters the injected inlet (point h in the figure) of the second ejector 107, and after being mixed by the second ejector 107, the gas-liquid two-phase working medium is changed into the gas-liquid two-phase working medium at the outlet of the second ejector 107 (point j in the figure); the residual working medium in the first liquid-separating condenser 103 continues to condense into liquid-phase working medium (point f in the figure), and enters the gas-separating evaporator 106 after being throttled in sequence by the second throttle valve 104 and the third throttle valve 105 (point g in the figure). The two-phase working medium (point j in the figure) at the outlet of the second ejector 107 is partially condensed by the second liquid-separating condenser 108, the liquid-phase working medium (point l in the figure) separated from the liquid-separating outlet of the second liquid-separating condenser 108 after the condensation enters the flash tank 110 (point m in the figure) by the first throttle 109; the residual working medium in the second liquid-splitting condenser 108 continues to condense into liquid-phase working medium (k point in the figure), and the liquid-phase working medium is mixed with the gas-liquid two-phase working medium at the outlet of the second throttle valve 104 and then enters the inlet of the third throttle valve 105. The gas-liquid separation is carried out in the flash tank 110, the saturated gas phase working medium (n point in the figure) at the gas phase outlet of the flash tank 110 enters the second air supplementing port 1014 of the multi-stage air supplementing compressor 101, and the saturated liquid phase working medium at the liquid phase outlet of the flash tank 110 enters the injection inlet (o point in the figure) of the first injector 111; separating evaporated gas phase working medium from a gas separation outlet of the gas separation evaporator 106, entering an ejected inlet (p point in the figure) of the first ejector 111, mixing the gas phase working medium with the liquid phase working medium at an outlet of the first ejector 111 (q point in the figure) after the first ejector 111 is mixed, evaporating the gas phase working medium by the high-pressure evaporator 112, and enabling the gas phase working medium at an outlet of the high-pressure evaporator 112 (r point in the figure) to enter a first air supplementing port 1013 of the multi-stage air supplementing compressor 101; the residual working medium in the gas-dividing evaporator 106 is continuously evaporated into gas-phase working medium (point a in the figure) and enters the inlet 1011 of the multi-stage air-supplementing compressor. In the boosting process, the gas phase working medium at the inlet 1011 of the multi-stage air-filling machine is sequentially mixed with the gas phase working medium at the first air-filling port 1013 and the second air-filling port 1014 of the multi-stage air-filling machine 101 (points b and c in the figure), and then leaves the outlet 1012 of the multi-stage air-filling machine. Part of the gas phase working medium (point d in the figure) at the outlet 1012 of the multi-stage air compressor enters the high-pressure compressor 102 to complete the whole circulation process.

Example 4

The following is an embodiment of a heat exchange system according to the present invention, including the multi-stage air supplementing injection high-temperature heat pump system, the heat sink side heat exchange module 113 and the heat source side heat exchange module 114, where the heat sink side heat exchange module 113 is sequentially communicated with the second split liquid condenser 108 and the first split liquid condenser 103, and the heat source side heat exchange module 114 is sequentially communicated with the high-pressure evaporator 112 and the split gas evaporator 106.

The heat exchange side heat exchange module 113 is used for exchanging heat with the second liquid separation condenser 108 and the first liquid separation condenser 103, and the heat source side heat exchange module 114 is used for exchanging heat with the high-pressure evaporator 112 and the gas separation evaporator 106, so that the functions of adjusting the working medium components and the flow rate can be realized by the internal structures of the second liquid separation condenser 108, the first liquid separation condenser 103, the high-pressure evaporator 112 and the gas separation evaporator 106.

In this embodiment, the heat sink side passes through the heat sink side of the second split liquid condenser 108 and then passes through the heat sink side of the first split liquid condenser 103, and the heat sink side and the working medium side are opposite in fluid flowing direction and are in a countercurrent heat exchange mode; the heat source side fluid passes through the heat source side of the high-pressure evaporator 112 and then passes through the heat source side of the gas separation evaporator 106, and the heat source side fluid and the working medium side fluid flow in opposite directions are in a countercurrent heat exchange mode.

Example 5

The following is an embodiment of a control method of a multi-stage air-supplementing injection type high-temperature heat pump system, which is applied to the multi-stage air-supplementing injection type high-temperature heat pump system and is operated as follows:

the working pressures of the first liquid-dividing condenser 103, the second liquid-dividing condenser 108, the second ejector 107, the multi-stage air-filling compressor 101, the flash tank 110, the first ejector 111, the high-pressure evaporator 112 and the gas-dividing evaporator 106 are respectively controlled and classified, the working pressure of the first liquid-dividing condenser 103 is defined as six-stage pressure, the working pressure of the second liquid-dividing condenser 108 and the working pressure of the second ejector 107 are five-stage pressure, the pressure of the outlet 1012 of the multi-stage air-filling compressor 101 is four-stage pressure, the working pressure of the flash tank 110 is three-stage pressure, the working pressure of the first ejector 111 and the working pressure of the high-pressure evaporator 112 are two-stage pressure, the working pressure of the gas-dividing evaporator 106 is one-stage pressure, and the working pressures of all parts meet the following conditions: six-level pressure > five-level pressure > four-level pressure > three-level pressure > two-level pressure > one-level pressure;

the liquid separation flow of the first liquid separation condenser 103 and the second liquid separation condenser 108, the gas separation flow of the gas separation evaporator 106 and the branch flow of the multi-stage air compressor 101 to the second ejector 107 are controlled, and the liquid separation flow of the first liquid separation condenser 103 is smaller than the main path flow of the first liquid separation condenser 103, the liquid separation flow of the second liquid separation condenser 108 is smaller than the main path flow of the second liquid separation condenser 108, the gas separation flow of the gas separation evaporator 106 is smaller than the main path flow of the gas separation evaporator 106, and the branch flow of the multi-stage air compressor 101 to the second ejector 107 is smaller than the branch flow of the multi-stage air compressor 101 to the first liquid separation condenser 103.

In this embodiment, the pressure of the liquid phase working medium from the liquid separation outlet of the first liquid separation condenser 103 in the second injector 107 is greater than the pressure of the gas phase working medium at the outlet 1012 of the multi-stage air compressor, and after the liquid phase working medium under six-stage pressure is used as working fluid to enter the second injector 107 to convert the pressure into speed, part of the gas phase working medium under four-stage pressure at the outlet 1012 of the multi-stage air compressor is ejected, and the gas-liquid two-phase working medium under five-stage pressure is formed at the outlet of the second injector 107. In practical application, the liquid-phase working medium under five-stage pressure at the liquid separation outlet of the second liquid separation condenser 108 is throttled and depressurized by the first throttle valve 109, and a gas-liquid two-phase working medium under three-stage pressure is formed at the inlet of the flash tank 110. The pressure of the liquid phase working medium from the liquid phase outlet of the flash tank 110 in the first ejector 111 is greater than the pressure of the gas phase working medium from the gas separation outlet of the gas separation evaporator 106, the liquid phase working medium under the three-stage pressure is used as working fluid to enter the first ejector 111 to convert the pressure into speed, and then the gas phase working medium under the primary pressure of the gas separation outlet of the gas separation evaporator 106 is ejected, and the gas-liquid two-phase working medium under the secondary pressure is formed at the outlet of the first ejector 111. Further, six different working pressures exist in the cyclic working process of the system, and the six-stage pressure, the five-stage pressure, the four-stage pressure, the three-stage pressure, the two-stage pressure and the one-stage pressure are sequentially arranged from high to low. Where the six-stage pressure and the one-stage pressure are determined by the operating conditions of the circulation system (i.e., a condensing temperature and an evaporating temperature), which in turn depend on the heating temperature requirements and the air ambient temperature.

In this embodiment, the multi-stage compression and intermediate cooling mode is adopted in the circulation, after the gas phase working medium at the inlet 1011 of the multi-stage air-compensating compressor is boosted, the gas phase working medium is mixed with the gas phase working medium at the first air-compensating port 1013 of the multi-stage air-compensating compressor 101, the mixed gas phase working medium is boosted again, the mixed gas phase working medium is mixed with the gas phase working medium at the second air-compensating port 1014 of the multi-stage air-compensating compressor 101, and the mixed gas phase working medium is boosted again and leaves the outlet 1012 of the multi-stage air-compensating compressor.

It is to be understood that the above examples of the present invention are provided by way of illustration only and not by way of limitation of the embodiments of the present invention. Other variations or modifications of the above teachings will be apparent to those of ordinary skill in the art. It is not necessary here nor is it exhaustive of all embodiments. Any modification, equivalent replacement, improvement, etc. which come within the spirit and principles of the invention are desired to be protected by the following claims.

Claims (10)

1. The multi-stage air supplementing injection type high-temperature heat pump system is characterized by comprising a multi-stage air supplementing compressor (101), a first liquid separating condenser (103), a first throttle valve (109), a flash tank (110), a first injector (111), a second throttle valve (104) and a gas separating evaporator (106);

the multistage air compressor outlet (1012) is communicated with the inlet of the first liquid separating condenser (103); one outlet of the first split liquid condenser (103) is communicated with an inlet of the flash tank (110) through a first throttle valve (109), and the other outlet of the first split liquid condenser (103) is communicated with an inlet of the split gas evaporator (106) through a second throttle valve (104); one of the outlets of the flash tank (110), the outlet of the first ejector (111) and one of the outlets of the split-gas evaporator (106) are respectively communicated with different inlets of the multi-stage air-filling compressor (101); the other outlet of the flash tank (110) is in communication with one of the inlets of the first ejector (111); the other outlet of the divided-gas evaporator (106) communicates with the other inlet of the first ejector (111).

2. The multi-stage make-up air injection high temperature heat pump system of claim 1, wherein the inlet of the multi-stage make-up air compressor (101) comprises at least a multi-stage make-up air compressor inlet (1011), a first make-up air port (1013), and a second make-up air port (1014), the outlet of the first injector (111) being in communication with the first make-up air port (1013), one of the outlets of the flash tank (110) being in communication with the second make-up air port (1014).

3. The multi-stage make-up air injection high temperature heat pump system according to claim 2, further comprising a high pressure evaporator (112), the outlet of the first injector (111) being in communication with the first make-up air port (1013) through the high pressure evaporator (112).

4. A multi-stage makeup air injection high temperature heat pump system according to claim 3, further comprising a second split condenser (108), a second ejector (107), a third throttle valve (105), a high pressure compressor (102), the outlet of the multi-stage makeup air compressor (101) being split into two paths, one of which communicates with the inlet of the first split condenser (103) through the high pressure compressor (102), the other of the multi-stage makeup air compressor (101) outlet communicating with the inlet of the second split condenser (108) through the second ejector (107); one outlet of the second liquid separating condenser (108) is communicated with an inlet of the flash tank (110) through the first throttle valve (109), and the other outlet of the second liquid separating condenser (108) is communicated with an inlet of the gas separating evaporator (106) through the third throttle valve (105).

5. The multi-stage air-make-up injection type high temperature heat pump system according to any one of claims 1 to 4, wherein the first liquid-separating condenser (103) comprises a condensation header (1032), a plurality of condensation heat exchange tubes (1031), a condensation liquid-separating tube (1033) and a liquid-separating partition plate (1034), a plurality of liquid-separating holes (1035) are formed in the liquid-separating partition plate (1034) in a penetrating manner, the liquid-separating partition plate (1034) is arranged in the condensation header (1032), the condensation heat exchange tubes (1031) are sequentially arranged and mutually communicated and are communicated with the condensation header (1032), the condensation liquid-separating tube (1033) is also communicated with the condensation header (1032), an inlet of the condensation header (1032) is communicated with an inlet of the second throttle valve (104), and the condensation liquid-separating tube (1033) is communicated with an inlet of the flash tank (110) through the first throttle valve (109).

6. The multi-stage make-up air injection type high temperature heat pump system according to any one of claims 1 to 4, wherein the air dividing evaporator (106) comprises an evaporation header (1062), a plurality of evaporation heat exchange tubes (1061), an evaporation air dividing pipe (1063) and an evaporation partition plate (1064), the evaporation partition plate (1064) is arranged on the evaporation header (1062), the evaporation heat exchange tubes (1061) are sequentially arranged and mutually communicated and are communicated with the evaporation header (1062), the evaporation air dividing pipe (1063) is also communicated with the evaporation header (1062), an inlet of the evaporation header (1062) is communicated with an outlet of the second throttle valve (104), an outlet of the evaporation header (1062) is communicated with an inlet (1011) of the multi-stage make-up air compressor, and the evaporation air dividing pipe (1063) is communicated with one of inlets of the first ejectors (111).

7. The multi-stage make-up air injection high temperature heat pump system of claim 1, wherein the inlet of the first injector (111) is divided into an injection inlet and an injected inlet, the injection inlet is communicated with the liquid phase outlet of the flash tank (110), and the injected inlet is communicated with the gas separation outlet of the gas separation evaporator (106).

8. The multi-stage makeup air injection high temperature heat pump system of claim 7, wherein the operating pressure of the injection inlet is greater than the operating pressure of the injected inlet.

9. A heat exchange system, characterized by comprising a multi-stage air supplementing injection type high-temperature heat pump system, a heat exchange side heat exchange module (113) and a heat source side heat exchange module (114) according to any one of claims 1 to 8, wherein the heat exchange side heat exchange module (113) is sequentially connected with the second partial liquid condenser (108) and the first partial liquid condenser (103), and the heat source side heat exchange module (114) is sequentially connected with the high-pressure evaporator (112) and the partial gas evaporator (106).

10. A control method of a multistage air-supplementing injection type high-temperature heat pump system, characterized by being applied to the multistage air-supplementing injection type high-temperature heat pump system according to any one of claims 4 to 9, and operating as follows:

the method comprises the steps of respectively controlling the working pressures of a first liquid separation condenser (103), a second liquid separation condenser (108), a second ejector (107), a multi-stage air supplementing compressor (101), a flash tank (110), a first ejector (111), a high-pressure evaporator (112) and a gas separation evaporator (106) and grading the pressures, defining the working pressure of the first liquid separation condenser (103) as six-stage pressure, defining the working pressure of the second liquid separation condenser (108) as five-stage pressure, defining the working pressure of the second ejector (107) as five-stage pressure, defining the pressure of an outlet (1012) of the multi-stage air supplementing compressor (101) as four-stage pressure, defining the working pressure of the flash tank (110) as three-stage pressure, defining the working pressure of the first ejector (111) as two-stage pressure, and defining the working pressure of the gas separation evaporator (106) as one-stage pressure, wherein the working pressures of all parts meet the following conditions: six-level pressure > five-level pressure > four-level pressure > three-level pressure > two-level pressure > one-level pressure;

controlling the liquid separating flow of the first liquid separating condenser (103) and the second liquid separating condenser (108), the gas separating flow of the gas separating evaporator (106), the branch flow of the multi-stage air supplementing compressor (101) to the second ejector (107), and enabling the liquid separating flow of the first liquid separating condenser (103) to be smaller than the main flow of the first liquid separating condenser (103), the liquid separating flow of the second liquid separating condenser (108) to be smaller than the main flow of the second liquid separating condenser (108), the gas separating flow of the gas separating evaporator (106) to be smaller than the main flow of the gas separating evaporator (106), and the branch flow of the multi-stage air supplementing compressor (101) to the second ejector (107) to be smaller than the branch flow of the multi-stage air supplementing compressor (101) to the first liquid separating condenser (103).