Heat pump cycle system with improved overall heat exchange process matching and operation method thereof

Abstract

The application discloses a heat exchanger capable of separating and supplementing liquid and a heat pump circulation system comprising the same. The heat exchanger can separate and supplement liquid for non-azeotropic mixed working medium, improve heat exchange matching between the non-azeotropic mixed working medium and a heat exchange fluid during condensation / phase change of the non-azeotropic mixed working medium, and reduce irreversible loss. On this basis, the heat pump circulation system of the application fully utilizes part of separated working medium in the condenser and the evaporator which does not participate in liquid supplement to realize heat exchange matching and collaborative improvement of the condensation process and the evaporation process of the non-azeotropic mixed working medium, and also creates favorable conditions for reducing the supercooling degree of the condenser outlet and the superheating degree of the evaporator outlet, improving single-phase heat exchange matching, and realizing heat exchange matching of the condensation, evaporation and single-phase heat exchange processes of the non-azeotropic mixed working medium at the same time. Therefore, the heat exchange whole-process matching of the heat pump system is improved, irreversible loss is reduced to the maximum extent, and the performance of the heat pump is improved.

Description

Technical Field

[0001] This invention relates to the field of heat pump technology, and specifically to a heat pump cycle system with improved matching throughout the heat exchange process and its operation method. Background Technology

[0002] Building energy consumption accounts for a significant proportion of global total energy consumption, with a large portion used for building heating and hot water production. According to statistics from the Tsinghua University Energy Conservation Building Research Center, in 2021, heating energy consumption in northern my country reached 212 million tons of standard coal equivalent, accounting for 19% of the country's total building energy consumption. The corresponding CO2 emissions were 490 million tons, representing 22.3% of total CO2 emissions from building operations. Promoting energy conservation and efficiency in building heating is crucial for reducing energy consumption and carbon dioxide emissions. Heat pumps, as a renewable energy utilization device, can convert low-grade heat energy in environmental media (water, air, soil, etc.) into high-grade heat energy for heating and hot water production. This highly efficient and energy-saving electro-thermal heating technology has been widely applied in the field of space heating and is one of the important ways to achieve building decarbonization.

[0003] The working fluid is the "blood" of a heat pump, and its development is inseparable from it. A non-azeotropic working fluid is a mixture of two or more pure working fluids with different boiling points. Non-azeotropic working fluids exhibit significant temperature glide during the gas-liquid phase change process. Utilizing this temperature glide allows for better matching of temperature changes between the cold and heat sources, approximating the Lorentz cycle. Compared to pure working fluids, this helps reduce irreversible heat exchange losses and improves heat pump performance.

[0004] In typical heat pump systems, the temperature glide of the non-azeotropic working fluid is essentially the same in both the evaporator and condenser. However, the temperature changes of the cold source on the condenser side and the heat source on the evaporator side are usually different. This makes it difficult to simultaneously achieve optimal heat transfer matching for the non-azeotropic mixture in both the condensation and evaporation phase change processes. Improving the heat transfer matching in one process often sacrifices the heat transfer matching in the other, thus offsetting the beneficial effects of the non-azeotropic mixture to some extent. This results in poor heat pump performance improvement, sometimes even worse than with a pure working fluid. Furthermore, the non-linear temperature-enthalpy relationship of the non-azeotropic mixture severely restricts the matching effect. This non-linear relationship means that the temperature change of the non-azeotropic mixture is not uniform with the enthalpy difference. Due to this non-linearity, the heat transfer temperature difference between the non-azeotropic mixture and the cold / heat source is not uniform, but rather has a temperature pinch point. This non-uniformity increases the irreversible heat loss of the condenser / evaporator. Furthermore, existing methods for improving heat exchange matching in heat pump cycles are based on phase change processes, which generally result in poor heat exchange matching for single-phase heat exchange processes in heat pumps. Although the heat transfer capacity of single-phase heat exchange in heat pumps is relatively small, research has found that reducing superheat to improve heat exchange matching can enhance the COP of the heat pump cycle.

[0005] Chinese patent application CN109611169A discloses a dynamically adjustable non-azeotropic working fluid organic Rankine cycle system, which can adjust the composition of the non-azeotropic working fluid on the condenser side without changing the composition of the non-azeotropic working fluid on the evaporator side; and vice versa. This achieves independent adjustment of the non-azeotropic working fluid composition on both heat exchanger sides, increasing the flexibility of adjustment and thus further improving system performance. CN114111076B discloses a modular non-azeotropic working fluid relay evaporation refrigeration system and its control method. By setting up multiple evaporation-compression modules, it utilizes the evaporation of the non-azeotropic working fluid under different pressures to achieve relay cooling of the heat source fluid temperature on the evaporator side. Simultaneously, it achieves temperature matching for heat exchange between the refrigerant and heat source fluid on the evaporator side and the refrigerant and heat source fluid on the condenser side under conditions of large temperature changes in the heat source fluid on the evaporator side. Utilizing a modular structure, the system achieves flexible adjustment of the heat source fluid temperature by controlling the number of operating evaporation-compression modules. However, the non-azeotropic working fluid heat pump systems reported so far mainly have the following problems: (1) After the system concentration is adjusted, the composition of the non-azeotropic working fluid in the condenser / evaporator is the same throughout the process, and the ineffective irreversible loss caused by the nonlinear temperature and enthalpy of the non-azeotropic working fluid is not considered; it is impossible to adjust the composition of the condensation process and the evaporation process, and completely improve the heat exchange matching of the condensation process and the evaporation process; (2) There is a lack of improvement on the single-phase heat exchange matching, which increases the complexity of the system, and the improvement of heat exchange matching is limited.

[0006] The phase transition process of non-azeotropic mixtures exhibits nonlinear temperature and enthalpy, specifically manifested as a temperature and enthalpy slope. It changes along the process and is related to the component (z) and dryness (x), that is... A mixed working fluid is composed of two or more different pure working fluids, and its components are also called components. During the phase change process of a non-azeotropic mixed working fluid, due to the difference in boiling points of the components, the higher-boiling-point component condenses first during condensation (becoming a high-boiling-point liquid working fluid), and the lower-boiling-point component vaporizes first during evaporation (leaving behind a high-boiling-point liquid working fluid). Therefore, the gas phase composition and liquid phase composition differ and change as the heat exchange process proceeds. If this characteristic is fully utilized, by separating the high-boiling-point liquid working fluid (liquid separation) or replenishing it (liquid replenishment), the composition, dryness, and flow rate of the non-azeotropic mixed working fluid can be actively and rationally reallocated, potentially achieving better heat exchange matching between the non-azeotropic working fluid and the cold / heat source. Meanwhile, utilizing a portion of the working fluid in the condenser and evaporator that does not participate in the replenishment process can achieve synergistic improvement in heat exchange matching between the condensation and evaporation processes of the non-azeotropic working fluid mixture. This also creates favorable conditions for reducing the subcooling at the condenser outlet and the superheat at the evaporator outlet, achieving optimal heat exchange matching for the condensation, evaporation, and single-phase heat exchange processes of the non-azeotropic working fluid mixture simultaneously. In other words, it achieves improved matching throughout the entire heat exchange process of the heat pump system, minimizing irreversible losses and enhancing heat pump performance. However, there are currently few reports on such technical solutions, and no corresponding dedicated devices have been reported. Summary of the Invention

[0007] The purpose of this invention is to address the above-mentioned problems by providing a heat pump cycle system and its operation method with improved matching throughout the heat exchange process. The heat pump cycle is constructed by considering the synergistic matching of condensation / evaporation with cold / heat source heat exchange and the improvement of single-phase heat exchange matching.

[0008] To achieve its objective, the present invention employs the following technical solution:

[0009] A heat exchanger capable of liquid separation / replenishment includes a parallel flow section and bends at both ends of the parallel flow section of the working fluid. Each U-shaped groove of the first pipe is provided with a second pipe. The second pipe includes a liquid separation pipe and a liquid replenishment pipe arranged parallel to the parallel flow section of the working fluid. The liquid separation pipe is close to the inlet end of the first pipe, and the liquid replenishment pipe is close to the outlet end of the first pipe. At least one connecting channel is provided between the liquid separation pipe and the parallel flow section of the working fluid above it, between the liquid replenishment pipe and the parallel flow section of the working fluid below it, and between the liquid separation pipe and the liquid replenishment pipe, so that the liquid separation pipe is connected to the first pipe, the liquid separation pipe is connected to the liquid replenishment pipe, and the liquid replenishment pipe is connected to the first pipe.

[0010] Liquid collection pipes are also provided on the left and right sides of the first pipe. The end of the replenishment pipe near the U-shaped groove of the first pipe extends outward and connects to the adjacent liquid collection pipe. The top of the liquid collection pipe is closed and the bottom is provided with a liquid outlet.

[0011] Preferably, the heat exchanger further includes a liquid collector and distributor, which includes a main pipe and multiple branch pipes. The liquid collectors on both sides of the heat exchanger are connected in parallel to the inlet end of the main pipe through pipes, and the outlet end of the main pipe branches into multiple branch pipes.

[0012] A heat pump cycle system with improved matching throughout the heat exchange process includes an intermediate regenerator and a compressor, heat exchanger A, a condenser-side regenerator, a throttling device, heat exchanger B, and an evaporator-side regenerator connected sequentially by pipes to form a heat exchange cycle. Heat exchanger A and heat exchanger B are heat exchangers as described in claim 1, with heat exchanger A serving as a condenser and heat exchanger B serving as an evaporator. A non-azeotropic working fluid flows through the first pipe of heat exchanger A and heat exchanger B, while a high-boiling-point component separated from the non-azeotropic working fluid in the first pipe flows through the second pipe and the liquid collection pipe.

[0013] The condenser-side regenerator is provided with a first heat exchange flow path and a second heat exchange flow path, the intermediate regenerator is provided with a third heat exchange flow path and a fourth heat exchange flow path, and the evaporator-side regenerator is provided with a fifth heat exchange flow path and a sixth heat exchange flow path.

[0014] The inlet of the first pipe A of heat exchanger A is connected to the exhaust port of the compressor; the outlet of the liquid collecting pipe A of heat exchanger A is connected to the inlet of the first heat exchange flow path, and the outlet of the liquid collecting pipe A is also connected to the inlet of the third heat exchange flow path. The outlet of the third heat exchange flow path and the outlet of the first pipe A merge at the first node and then connect to the inlet of the second heat exchange flow path.

[0015] After the outlets of the first and second heat exchange flow paths merge, they are connected to the inlet of the first pipe B of heat exchanger B through the throttling device. The outlet of the liquid collecting pipe B of heat exchanger B is connected to the inlet of the fourth heat exchange flow path. The outlet of the fourth heat exchange flow path and the outlet of the first pipe B merge at the second node and are connected to the inlet of the fifth heat exchange flow path. The outlet of the liquid collecting pipe B is also connected to the inlet of the sixth heat exchange flow path. After the outlets of the fifth and sixth heat exchange flow paths merge, they are connected to the inlet of the compressor.

[0016] Preferably, in the heat pump cycle system, heat exchanger A and heat exchanger B are the aforementioned heat exchangers;

[0017] The intermediate regenerator has a third heat exchange flow path with multiple first branch pipes connected in parallel on the third heat exchange flow path. The inlet end of the third heat exchange flow path is connected to a liquid distribution branch pipe A of heat exchanger A, and the first branch pipe is connected to other liquid distribution branch pipes A of heat exchanger A.

[0018] The fourth heat exchange flow path of the intermediate regenerator is provided with multiple second branch pipes connected in parallel on the fourth heat exchange flow path. The inlet end of the fourth heat exchange flow path is connected to one liquid distribution branch pipe B of the heat exchanger B, and the second branch pipe is connected to other liquid distribution branch pipes B of the heat exchanger B.

[0019] Preferably, the heat exchanger A has three liquid distribution branches A, one of which is connected to the inlet of the first heat exchange flow path, and the other is connected to the inlet of the third heat exchange flow path. The plurality of first branches are connected in parallel to the remaining liquid distribution branches A.

[0020] The heat exchanger B has three liquid distribution branches B. One liquid distribution branch B is connected to the inlet end of the sixth heat exchange flow path, and one liquid distribution branch B is connected to the inlet end of the fourth heat exchange flow path. The multiple second branches are connected in parallel to the remaining liquid distribution branches B.

[0021] Preferably, the throttling device is a throttling valve.

[0022] Preferably, a three-way valve is provided at the first node and the second node.

[0023] A method for operating a heat pump cycle system as described in any one of the above claims includes the following steps: introducing a non-azeotropic working fluid into the heat pump cycle system, turning on the compressor and the throttling device, and running the system; the non-azeotropic working fluid sequentially passes through the compressor, heat exchanger A, condenser-side regenerator, throttling device, heat exchanger B, and evaporator-side regenerator before returning to the compressor; a portion of the high-boiling-point component in the liquid collector A of heat exchanger A enters the first heat exchange path of the condenser-side regenerator, and a portion enters the third heat exchange path of the intermediate regenerator; a portion of the high-boiling-point component in the liquid collector B of heat exchanger B enters the fourth heat exchange path of the intermediate regenerator, and a portion enters the sixth heat exchange path of the evaporator-side regenerator. In the intermediate regenerator, the third and fourth heat exchange flow paths exchange heat. The working fluid from the third heat exchange flow path merges with the working fluid from the first pipe A of heat exchanger A at the first node and then enters the first heat exchange flow path in the condenser-side regenerator. The first heat exchange flow path exchanges heat with the second heat exchange flow path. After the outlets of the first and second heat exchange flow paths merge, they enter the throttling device together. The working fluid from the fourth heat exchange flow path merges with the working fluid from the first pipe B of heat exchanger B at the second node and then enters the fifth heat exchange flow path of the evaporator-side regenerator. The fifth heat exchange flow path exchanges heat with the sixth heat exchange flow path. After the outlets of the fifth and sixth heat exchange flow paths merge, they enter the compressor together.

[0024] Preferably, in the technical solution of the operating method, the non-azeotropic working fluid is a binary non-azeotropic working fluid.

[0025] Preferably, in the technical solution of the operation method, the external cold source of heat exchanger A is air or water, and the external heat source of heat exchanger B is air or water.

[0026] The beneficial effects of this invention are:

[0027] The heat exchanger and heat pump system of this invention can perform liquid separation / replenishment of the non-azeotropic working fluid in the condenser and evaporator, and can adjust the dryness, composition and flow rate of the non-azeotropic working fluid, thereby improving the heat exchange matching between the non-azeotropic working fluid and the heat exchange fluid during the condensation / phase change process and reducing irreversible losses. At the same time, by using a portion of the separated working fluid in the condenser and evaporator that does not participate in the replenishment, the heat exchange matching of the condensation and evaporation processes of the non-azeotropic working fluid can be synergistically improved. It also creates favorable conditions for reducing the subcooling at the condenser outlet and the superheat at the evaporator outlet, so that the heat exchange matching of the condensation, evaporation and single-phase heat exchange processes of the non-azeotropic working fluid can be optimized simultaneously. That is, the heat exchange matching of the entire heat exchange process of the heat pump system is improved, the irreversible losses are reduced to the greatest extent, and the heat pump performance is improved.

[0028] The steps for improving the matching of the entire heat exchange process in the heat pump cycle system in this invention are as follows:

[0029] (1) The heat exchange matching of the non-azeotropic working fluid condensation and evaporation processes is completely improved: In the condenser, by repeatedly performing liquid separation and replenishment, the composition, dryness and flow rate of the non-azeotropic working fluid are adjusted, thereby completely improving the heat exchange matching between the non-azeotropic working fluid and the cold source and reducing the irreversible loss of two-phase heat exchange during the condensation process; similarly, in the evaporator, by repeatedly performing liquid separation, the composition, dryness and flow rate of the non-azeotropic working fluid are adjusted, thereby completely improving the heat exchange matching between the non-azeotropic working fluid and the heat source and reducing the irreversible loss of two-phase heat exchange during the evaporation process;

[0030] (2) Improved heat exchange matching between condenser and evaporator: Some of the separation working fluids that do not participate in the replenishment of liquid in the condenser and evaporator exchange heat, thereby coordinating the liquid separation / replenishment in the condenser and evaporator and improving the heat exchange matching between the condenser and evaporator.

[0031] (3) Improvement of single-phase heat exchange matching: Under the premise of ensuring the necessary subcooling at the condenser outlet and the necessary superheat at the evaporator outlet, the heat exchange matching of the single-phase heat exchange process is improved by using the separation working fluid in the condenser and evaporator that does not participate in the liquid replenishment, thereby further reducing the irreversible losses of the single-phase heat exchange process of the non-azeotropic mixed working fluid.

[0032] (4) Analyze the heat exchange matching degree between the two-phase section and the single-phase section in the condenser and evaporator and the cold / heat source, respectively, as well as the heat exchange matching degree of the separation working fluid in the condenser and evaporator that does not participate in the replenishment.

[0033] (5) Adjust the liquid separation, liquid replenishment and separation of the working fluid in the condenser and evaporator, thereby adjusting the heat exchange matching and single-phase heat exchange matching in the condensation / evaporation process of the non-azeotropic mixed working fluid. (1) to (4) can be repeated until the heat exchange matching of each process reaches the best at the same time, so as to realize the matching improvement of the entire heat exchange process of the heat pump cycle and maximize the performance of the heat pump.

[0034] This invention, based on the complete improvement of heat exchange matching in the condensation and evaporation processes of non-azeotropic working fluids through multiple liquid separation and replenishment processes, fully utilizes the separated working fluid in the condenser and evaporator that does not participate in replenishment to achieve synergistic improvement in heat exchange matching in the condensation and evaporation processes of non-azeotropic working fluids. At the same time, it creates favorable conditions for reducing the subcooling at the condenser outlet and the superheat at the evaporator outlet, so as to achieve optimal heat exchange matching in the condensation, evaporation and single-phase heat exchange processes of non-azeotropic working fluids at the same time. That is, it realizes the matching improvement of the entire heat exchange process of the heat pump system, minimizes irreversible losses, and improves the performance of the heat pump. Attached Figure Description

[0035] Figure 1 This is a schematic diagram of the heat pump cycle system of the present invention;

[0036] Figure 2 yes Figure 1 Schematic diagram of heat exchanger A in the middle section;

[0037] Figure 3 yes Figure 1 Schematic diagram of the structure of heat exchanger B in the middle section;

[0038] Figure 4 yes Figure 1 A schematic diagram showing the connection relationship between the liquid distribution branch of the liquid collector and the third and fourth heat exchange flow paths of the intermediate regenerator.

[0039] The elements or structures indicated by the reference numerals in the attached drawings are:

[0040] Compressor 1, condenser-side regenerator 3, throttling device 4, evaporator-side regenerator 6, intermediate regenerator 7, first heat exchange flow path 8, second heat exchange flow path 9, third heat exchange flow path 10, first branch pipe 10a, fourth heat exchange flow path 11, second branch pipe 11a, fifth heat exchange flow path 12, sixth heat exchange flow path 13, first node 14, second node 15;

[0041] Heat exchanger A2, first pipe A201, parallel section of working fluid flow A202, bend A203, second pipe A204, liquid distribution pipe A205, liquid replenishment pipe A206, connecting channel A207, liquid collecting pipe A208, liquid collecting and liquid distributing device A209, main pipe A210, liquid distribution branch pipe A211;

[0042] Heat exchanger B5, first pipe B501, parallel section of working fluid flow B502, bend B503, second pipe B504, liquid separator B505, liquid replenishment pipe B506, connecting channel B507, liquid collecting pipe B508, liquid collector and distributor B509, main pipe B510, liquid branch pipe B511.

[0043] Figure 5 This is a schematic diagram of the working principle of the heat pump cycle system of the present invention. Detailed Implementation

[0044] The present invention will be further described below with reference to embodiments, but these embodiments are not intended to limit the scope of the invention.

[0045] Unless otherwise specified, the experimental methods described in the following examples are conventional methods.

[0046] Example 1: A heat exchanger capable of liquid separation / replenishment.

[0047] like Figure 2The heat exchanger A2 shown is a liquid-dispensing / replenishing heat exchanger, the main body of which is a first pipe A201 arranged in a serpentine shape. The first pipe A201 includes multiple parallel working fluid flow sections A202 arranged vertically and horizontally, and bends A203 located at both ends of the parallel working fluid flow sections A202. Each U-shaped groove of the first pipe A201 is provided with a second pipe A204. The second pipe A204 includes a liquid-dispensing pipe A205 and a replenishment pipe A206 arranged parallel to the working fluid flow sections A202. The liquid-dispensing pipe A205 is connected to the first... The inlet end of pipe A201 is close to the outlet end of the first pipe A201. At least one connecting channel A207 is provided between the distributor pipe A205 and the parallel working fluid flow section A202 above it, between the distributor pipe A206 and the parallel working fluid flow section A202 below it, and between the distributor pipe A205 and the distributor pipe A206. This allows the distributor pipe A205 to connect with the first pipe A201, the distributor pipe A205 to the distributor pipe A206, and the distributor pipe A206 to connect with the first pipe A201. A collection pipe A208 is also provided on the left and right sides of the first pipe A201. One end of the distributor pipe A206 near the U-shaped groove opening of the first pipe A201 extends outward and connects to the adjacent collection pipe A208. The top of the collection pipe A208 is closed, and the bottom end is provided with an outlet.

[0048] In some implementations, heat exchanger A2 further includes a liquid collector and distributor A209, which includes a main pipe A210 and multiple branch pipes A211. The liquid collectors A208 on both sides of heat exchanger A2 are connected in parallel to the inlet end of the main pipe A210 via pipes, and the outlet end of the main pipe A210 branches into multiple branch pipes A211.

[0049] like Figure 3The heat exchanger B 5 shown is a liquid-dispensing / replenishing heat exchanger. Its main body is a first pipe B 501 arranged in a serpentine pattern. The first pipe B 501 includes multiple parallel working fluid flow sections B 502 arranged vertically and horizontally, and bends B 503 located at both ends of the parallel working fluid flow sections B 502. A second pipe B 504 is installed in each U-shaped groove of the first pipe B 501. The second pipe B 504 includes a liquid-dispensing pipe B 505 and a liquid-replenishing pipe B 506 arranged parallel to the working fluid flow sections B 502. The liquid-dispensing pipe B 505 is close to the inlet end of the first pipe B 501, and the liquid-replenishing pipe B 506 is close to the outlet end of the first pipe B 501. The liquid-dispensing pipe B 505 is positioned close to the working fluid flow section B 502 above it, the liquid-replenishing pipe B 506 is positioned close to the working fluid flow section B 502 below it, and the liquid-dispensing pipe B 505 and the liquid-replenishing pipe B 506 are positioned close to each other. At least one connecting channel B 507 is provided between each of 506, so that the liquid distribution pipe B505 is connected to the first pipe B 501, the liquid distribution pipe B 505 is connected to the replenishment pipe B 506, and the replenishment pipe B 506 is connected to the first pipe B501; a liquid collection pipe B 508 is also provided on the left and right sides of the first pipe B 501 respectively, and the end of the replenishment pipe B 506 near the U-shaped groove of the first pipe B 501 extends outward and connects to the adjacent liquid collection pipe B 508. The top of the liquid collection pipe B 508 is closed and the bottom is provided with a liquid outlet.

[0050] In some embodiments, heat exchanger B5 further includes a liquid collector and distributor B509, which includes a main pipe B510 and multiple branch pipes B511. The liquid collectors B508 on both sides of heat exchanger B5 are connected in parallel to the inlet end of the main pipe B510 through pipes, and the outlet end of the main pipe B510 branches into multiple branch pipes B511.

[0051] In fact, heat exchanger A2 and heat exchanger B5 have the same structure, except that they are used as condenser and evaporator respectively in the heat pump cycle system of Example 2.

[0052] Example 2: A heat pump cycle system with improved matching throughout the heat exchange process.

[0053] like Figure 1-4The heat pump cycle system shown includes an intermediate regenerator 7 and a compressor 1, a heat exchanger A 2, a condenser-side regenerator 3, a throttling device 4, a heat exchanger B 5, and an evaporator-side regenerator 6, which are connected sequentially by pipes to form a heat exchange cycle. The structures of heat exchangers A 2 and B 5 are the same as those in Example 1. In the heat pump cycle system of this invention, heat exchanger A 2 serves as a condenser, and heat exchanger B 5 serves as an evaporator. A non-azeotropic working fluid flows through the first pipe of heat exchangers A 2 and B 5, while a high-boiling-point component separated from the non-azeotropic working fluid in the first pipe flows through the second pipe and the liquid collection pipe.

[0054] The condenser-side regenerator 3 is provided with a first heat exchange flow path 8 and a second heat exchange flow path 9, the intermediate regenerator 7 is provided with a third heat exchange flow path 10 and a fourth heat exchange flow path 11, and the evaporator-side regenerator 6 is provided with a fifth heat exchange flow path 12 and a sixth heat exchange flow path 13.

[0055] The inlet of the first pipe A201 of heat exchanger A2 is connected to the exhaust port of compressor 1; the outlet of the liquid collecting pipe A208 of heat exchanger A2 is connected to the inlet of the first heat exchange flow path 8, and the outlet of the liquid collecting pipe A208 is also connected to the inlet of the third heat exchange flow path 10. The outlet of the third heat exchange flow path 10 and the outlet of the first pipe A201 merge at the first node 14 and then connect to the inlet of the second heat exchange flow path 9.

[0056] After the outlets of the first heat exchange flow path 8 and the second heat exchange flow path 9 merge, they are connected to the inlet of the first pipe B 501 of the heat exchanger B 5 through the throttling device 4. The outlet of the liquid collecting pipe B 508 of the heat exchanger B 5 is connected to the inlet of the fourth heat exchange flow path 11. The outlet of the fourth heat exchange flow path 11 and the outlet of the first pipe B 501 merge at the second node 15 and are connected to the inlet of the fifth heat exchange flow path 12. The outlet of the liquid collecting pipe B 508 is also connected to the inlet of the sixth heat exchange flow path 13. After the outlets of the fifth heat exchange flow path 12 and the sixth heat exchange flow path 13 merge, they are connected to the inlet of the compressor 1.

[0057] In some implementations, the third heat exchange flow path 10 of the intermediate regenerator 7 is provided with multiple first branch pipes 10a connected in parallel to the third heat exchange flow path 10. The inlet end of the third heat exchange flow path 10 is connected to a liquid distribution branch pipe A of heat exchanger A2, and the first branch pipes 10a are connected to other liquid distribution branch pipes A of heat exchanger A2. The fourth heat exchange flow path 11 of the intermediate regenerator 7 is provided with multiple second branch pipes 11a connected in parallel to the fourth heat exchange flow path 11. The inlet end of the fourth heat exchange flow path 11 is connected to a liquid distribution branch pipe B511 of heat exchanger B5, and the second branch pipes 11a are connected to other liquid distribution branch pipes B511 of heat exchanger B5. A first branch pipe 10a and a second branch pipe 11a are provided in the third heat exchange flow path 10 and the fourth heat exchange flow path 11, so that the high-boiling-point liquid working fluid in the liquid collectors of heat exchanger A2 and heat exchanger B5 can be replenished into the third heat exchange flow path 10 and the fourth heat exchange flow path 11 through the first branch pipe 10a and the second branch pipe 11a, respectively. This coordinates the heat exchange matching degree between the third heat exchange flow path 10 and the fourth heat exchange flow path 11 in the intermediate regenerator 7, that is, coordinates the heat exchange matching degree of the separation working fluid in the condenser and evaporator that does not participate in the replenishment.

[0058] In some implementations, heat exchanger A2 has three liquid distribution branches A, one of which is connected to the inlet of the first heat exchange flow path 8, and the other is connected to the inlet of the third heat exchange flow path 10. Multiple first branches 10a are connected in parallel to the remaining liquid distribution branches A. Heat exchanger B5 has three liquid distribution branches B511, one of which is connected to the inlet of the sixth heat exchange flow path 13, and the other is connected to the inlet of the fourth heat exchange flow path 11. Multiple second branches 11a are connected in parallel to the remaining liquid distribution branches B511.

[0059] In some implementations, the throttling device 4 is a throttling valve.

[0060] In some implementations, a three-way valve is provided at the first node 14 and the second node 15.

[0061] Example 3: Operation method of heat pump cycle system

[0062] An operation method of a heat pump cycle system according to Embodiment 2 includes the following steps: A non-azeotropic working fluid is introduced into the heat pump cycle system; compressor 1 and throttling device 4 are turned on; the system is started; the non-azeotropic working fluid sequentially passes through compressor 1, heat exchanger A2, condenser-side regenerator 3, throttling device 4, heat exchanger B5, and evaporator-side regenerator 6 before reaching compressor 1; a portion of the high-boiling-point component in the liquid collection pipe A208 of heat exchanger A2 enters the first heat exchange flow path 8, and a portion enters the third heat exchange flow path 10; a portion of the high-boiling-point component in the liquid collection pipe B508 of heat exchanger B5 enters the fourth heat exchange flow path 11, and a portion enters the sixth heat exchange flow path 13; the third heat exchange flow path 10 and the fourth heat exchange flow path 11 in the intermediate regenerator 7 exchange heat; the working fluid exiting the third heat exchange flow path 10 interacts with the first pipe A of heat exchanger A2. The working fluid exiting from heat exchanger A2 merges with the first heat exchange path 8 in the condenser-side regenerator 3 at the first node 14. Heat exchange path 8 then exchanges heat with the second heat exchange path 9. The outlets of the first and second heat exchange paths 8 and 9 merge and enter the throttling device 4. The working fluid exiting from the fourth heat exchange path 11 merges with the working fluid exiting from the first pipe B501 of heat exchanger B5 at the second node 15 and enters the fifth heat exchange path 12 of the evaporator-side regenerator. Heat exchange path 12 exchanges heat with the sixth heat exchange path 13. The outlets of the fifth and sixth heat exchange paths 12 and 13 merge and enter the compressor 1. The external cold source for heat exchanger A2 is air or water, and the external heat source for heat exchanger B5 is air or water.

[0063] The working principle of the heat pump cycle system with improved heat exchange process matching in this invention is as follows: Figure 5 As shown, its working process is as follows:

[0064] The high-temperature, high-pressure gaseous non-azeotropic working fluid discharged from compressor 1 enters heat exchanger A2 (i.e., condenser) for condensation. During the condensation process, due to the difference in boiling points of the components of the non-azeotropic working fluid, the higher-boiling-point component will condense first, becoming a high-boiling-point liquid working fluid. At this time, a portion of the high-boiling-point liquid working fluid is separated from the first pipe A201 and enters the separator A205, thereby adjusting the composition, dryness, and flow rate of the non-azeotropic working fluid in the first pipe A201, and improving the heat exchange matching between the non-azeotropic working fluid in the first pipe A201 and the cold source. The high-boiling-point liquid working fluid separated from the non-azeotropic mixture in the first pipe A201 of heat exchanger A2 is divided into two parts: the first part is used to replenish the first pipe A201 of heat exchanger A2. When the heat exchange matching between the non-azeotropic mixture in the first pipe A201 and the cold source deteriorates, the high-boiling-point liquid working fluid in the distribution pipe A205 enters the replenishment pipe A206 through the connecting channel A207, and then re-enters the first pipe A201 through the connecting channel between the replenishment pipe A206 and the parallel section A202 of the working fluid flow below it, readjusting the composition, dryness and flow rate of the non-azeotropic mixture in the first pipe A201, so that the heat exchange matching between the non-azeotropic mixture and the cold source is improved again; the second part does not participate in the replenishment of the first pipe A201, and enters the adjacent collection pipe A208 from the replenishment pipe A206. Through multiple liquid distribution and replenishment processes via multiple liquid distribution pipes A 205 located above and below, the heat exchange matching of the non-azeotropic mixed working fluid condensation process can be completely improved, greatly reducing irreversible losses.

[0065] The working fluid that does not participate in the replenishment in the liquid collecting pipes A 208 on both sides of heat exchanger A2 enters the liquid collecting and distributing device A209 through the main pipe A 210. Part of it enters the first heat exchange flow path 8 of the condensing side regenerator 3 through a distributing branch pipe A211, part of it enters the inlet end of the third heat exchange flow path 10 of the intermediate regenerator 7 through a distributing branch pipe A 211, and part of it enters multiple first branch pipes 10a of the third heat exchange flow path 10 of the intermediate regenerator 7 through a distributing branch pipe A211.

[0066] The working fluid exiting the third heat exchange path 10 of the intermediate regenerator 7 and the working fluid exiting the first pipe A201 of heat exchanger A2 merge at the first node 14 and then exchange heat with the first heat exchange path 8 and the second heat exchange path 9 in the condenser-side regenerator 3. While ensuring the necessary subcooling at the outlet of heat exchanger A2, the separation working fluid in heat exchanger A2, which does not participate in the replenishment, reduces the subcooling at the outlet of heat exchanger A2, improves the heat exchange matching of the single-phase heat exchange process of the non-azeotropic mixture, and further reduces the irreversible losses of the single-phase heat exchange process of the non-azeotropic mixture. The outlets of the first heat exchange path 8 and the second heat exchange path 9 merge and then enter the throttling device 4.

[0067] Similarly, the low-temperature, low-pressure non-azeotropic working fluid exiting from the throttling device 4 enters the first pipe B501 of the heat exchanger B5 (i.e., the evaporator) for evaporation. During evaporation, the unevaporated high-boiling-point liquid working fluid can be separated from the first pipe B501 through the connecting channel B507 and enter the separator B505. This adjusts the composition, dryness, and flow rate of the non-azeotropic working fluid in the first pipe B501, thereby improving the heat exchange matching between the non-azeotropic working fluid and the heat source. The high-boiling-point liquid working fluid separated from the non-azeotropic mixture in the first pipe B501 is divided into two parts: the first part is used to replenish the first pipe B501 of the heat exchanger B5. When the heat exchange matching between the non-azeotropic mixture in the first pipe B501 and the heat source deteriorates, the high-boiling-point liquid working fluid in the distribution pipe B505 enters the replenishment pipe B506 through the connecting pipe B507, and then re-enters the first pipe B501 through the connecting channel B507 between the replenishment pipe B506 and the parallel section B502 of the working fluid flow below it, readjusting the composition, dryness, and flow rate of the non-azeotropic mixture, so that the heat exchange matching between the non-azeotropic mixture and the heat source is improved again; the second part does not participate in the replenishment of the first pipe B501, and enters the adjacent collection pipe B508 from the replenishment pipe B506. By repeatedly separating and replenishing the liquid, the heat exchange matching of the non-azeotropic mixed working fluid evaporation process can be completely improved, greatly reducing irreversible losses.

[0068] The working fluid that does not participate in the replenishment in the liquid collecting pipes B 508 on both sides of heat exchanger B5 enters the liquid collecting and distributing device B 509 through the main pipe B 510. Part of it enters the fifth heat exchange flow path 12 of the evaporation-side regenerator 6 through a distributing branch pipe B 511, part of it enters the inlet end of the fourth heat exchange flow path 11 of the intermediate regenerator 7 through a distributing branch pipe B 511, and part of it enters multiple first branch pipes 11a of the fourth heat exchange flow path 11 of the intermediate regenerator 7 through a distributing branch pipe B 511.

[0069] In the intermediate regenerator 7, the third flow path 10 and the fourth flow path 11 exchange heat. The high-boiling-point liquid working fluid in the liquid collectors A209 and B509 of heat exchangers A2 and B5 can be supplemented into the third heat exchange flow path 10 and the fourth heat exchange flow path 11 through the first branch pipe 10a and the second branch pipe 11a, respectively, to coordinate the heat exchange matching degree between the third heat exchange flow path 10 and the fourth heat exchange flow path 11 in the intermediate regenerator 7, that is, to coordinate the heat exchange matching degree of the separation working fluids in the condenser and evaporator that do not participate in the replenishment.

[0070] The working fluid exiting the fourth heat exchange path 11 of the intermediate regenerator 7 merges with the working fluid exiting the first pipe B501 of heat exchanger B5 and enters the fifth heat exchange path 12 of the evaporator-side regenerator 6, where it exchanges heat with the sixth heat exchange path 13. While ensuring the necessary superheat at the outlet of heat exchanger B5, the separated working fluid in heat exchanger B5, which does not participate in the replenishment, reduces the superheat at the outlet of heat exchanger B5, improving the heat exchange matching of the single-phase heat exchange process of the non-azeotropic mixture, and further reducing the irreversible losses in the single-phase heat exchange process of the non-azeotropic mixture. The outlets of the fifth heat exchange path 12 and the sixth heat exchange path 13 merge and enter the compressor 1 together. This completes the entire heat pump cycle, achieving improved matching throughout the entire heat pump cycle heat exchange process.

[0071] Based on the type of non-azeotropic working fluid, the parameters of each component of the heat pump system, and the system operating parameters, the parameters, positions, and quantities of the connecting channels between the distributor pipe and the parallel section of the working fluid flow above it, between the makeup pipe and the parallel section of the working fluid flow below it, and between the distributor pipe and the makeup pipe, as well as the arrangement of the distributor branch pipes of the liquid collector, are adjusted (i.e., based on different non-azeotropic working fluids, different components of the heat pump system, and different system operating parameters, suitable heat exchanger structural parameters can be obtained through pre-experiments, thereby achieving optimal heat exchange matching throughout the entire heat exchange process of the heat pump system). This adjusts the distribution of the liquid in the condenser and evaporator, the makeup in the condenser, and the distribution of the separated working fluid, thereby adjusting the heat exchange matching and single-phase heat exchange matching during the condensation / evaporation process of the non-azeotropic working fluid. The intermediate regenerator 7, the condenser-side regenerator 3, and the evaporator-side regenerator 6 work together to improve the heat exchange matching of the condensation, evaporation, and single-phase heat exchange processes of the non-azeotropic working fluid, achieving optimal heat exchange matching and improving the matching of the entire heat exchange process of the heat pump cycle, thereby enhancing the performance of the heat pump.

Claims

1. A heat exchanger capable of liquid separation / replenishment, characterized in that: The main body of the heat exchanger is a first pipe arranged in a serpentine shape. The first pipe includes multiple parallel working fluid flow sections arranged vertically and horizontally, and bends at both ends of the parallel working fluid flow sections. A second pipe is provided in each U-shaped groove of the first pipe. The second pipe includes a liquid distribution pipe and a liquid replenishment pipe arranged parallel to the working fluid flow sections. The liquid distribution pipe is close to the inlet end of the first pipe, and the liquid replenishment pipe is close to the outlet end of the first pipe. At least one connecting channel is provided between the liquid distribution pipe and the working fluid flow section above it, between the liquid replenishment pipe and the working fluid flow section below it, and between the liquid distribution pipe and the liquid replenishment pipe, so that the liquid distribution pipe is connected to the first pipe, the liquid distribution pipe is connected to the liquid replenishment pipe, and the liquid replenishment pipe is connected to the first pipe. Liquid collection pipes are also provided on the left and right sides of the first pipe. The end of the replenishment pipe near the U-shaped groove of the first pipe extends outward and connects to the adjacent liquid collection pipe. The top of the liquid collection pipe is closed and the bottom is provided with a liquid outlet.

2. The heat exchanger according to claim 1, characterized in that: It also includes a liquid collector and distributor, which includes a main pipe and multiple branch pipes. The liquid collectors on both sides of the heat exchanger are connected in parallel to the inlet end of the main pipe through pipes, and the outlet end of the main pipe branches into multiple branch pipes.

3. A heat pump cycle system with improved matching throughout the heat exchange process, characterized in that: It includes an intermediate regenerator and a compressor, heat exchanger A, a condenser-side regenerator, a throttling device, heat exchanger B, and an evaporator-side regenerator that are connected in sequence through pipes to form a heat exchange cycle. The heat exchangers A and B are heat exchangers as described in claim 1, with heat exchanger A serving as a condenser and heat exchanger B serving as an evaporator. A non-azeotropic working fluid flows through the first pipe of heat exchangers A and B, while a high-boiling-point component separated from the non-azeotropic working fluid in the first pipe flows through the second pipe and the liquid collection pipe. The condenser-side regenerator is provided with a first heat exchange flow path and a second heat exchange flow path, the intermediate regenerator is provided with a third heat exchange flow path and a fourth heat exchange flow path, and the evaporator-side regenerator is provided with a fifth heat exchange flow path and a sixth heat exchange flow path. The inlet of the first pipe A of heat exchanger A is connected to the exhaust port of the compressor; the outlet of the liquid collecting pipe A of heat exchanger A is connected to the inlet of the first heat exchange flow path, and the outlet of the liquid collecting pipe A is also connected to the inlet of the third heat exchange flow path. The outlet of the third heat exchange flow path and the outlet of the first pipe A merge at the first node and then connect to the inlet of the second heat exchange flow path. After the outlets of the first and second heat exchange flow paths merge, they are connected to the inlet of the first pipe B of heat exchanger B through the throttling device. The outlet of the liquid collecting pipe B of heat exchanger B is connected to the inlet of the fourth heat exchange flow path. The outlet of the fourth heat exchange flow path and the outlet of the first pipe B merge at the second node and are connected to the inlet of the fifth heat exchange flow path. The outlet of the liquid collecting pipe B is also connected to the inlet of the sixth heat exchange flow path. After the outlets of the fifth and sixth heat exchange flow paths merge, they are connected to the inlet of the compressor.

4. A heat pump cycle system with improved matching throughout the heat exchange process, characterized in that: It includes an intermediate regenerator and a compressor, heat exchanger A, a condenser-side regenerator, a throttling device, heat exchanger B, and an evaporator-side regenerator that are connected in sequence through pipes to form a heat exchange cycle. The heat exchangers A and B are the heat exchangers described in claim 2, with heat exchanger A serving as a condenser and heat exchanger B serving as an evaporator. A non-azeotropic working fluid flows through the first pipe of heat exchangers A and B, while a high-boiling-point component separated from the non-azeotropic working fluid in the first pipe flows through the second pipe and the liquid collection pipe. The condenser-side regenerator is provided with a first heat exchange flow path and a second heat exchange flow path, the intermediate regenerator is provided with a third heat exchange flow path and a fourth heat exchange flow path, and the evaporator-side regenerator is provided with a fifth heat exchange flow path and a sixth heat exchange flow path. The inlet of the first pipe A of heat exchanger A is connected to the exhaust port of the compressor; the outlet of the liquid collecting pipe A of heat exchanger A is connected to the inlet of the first heat exchange flow path, and the outlet of the liquid collecting pipe A is also connected to the inlet of the third heat exchange flow path. The outlet of the third heat exchange flow path and the outlet of the first pipe A merge at the first node and then connect to the inlet of the second heat exchange flow path. After the outlets of the first and second heat exchange flow paths merge, they are connected to the inlet of the first pipe B of heat exchanger B through the throttling device. The outlet of the liquid collecting pipe B of heat exchanger B is connected to the inlet of the fourth heat exchange flow path. The outlet of the fourth heat exchange flow path and the outlet of the first pipe B merge at the second node and are connected to the inlet of the fifth heat exchange flow path. The outlet of the liquid collecting pipe B is also connected to the inlet of the sixth heat exchange flow path. After the outlets of the fifth and sixth heat exchange flow paths merge, they are connected to the inlet of the compressor. The intermediate regenerator has a third heat exchange flow path with multiple first branch pipes connected in parallel on the third heat exchange flow path. The inlet end of the third heat exchange flow path is connected to a liquid distribution branch pipe A of heat exchanger A, and the first branch pipe is connected to other liquid distribution branch pipes A of heat exchanger A. The fourth heat exchange flow path of the intermediate regenerator is provided with multiple second branch pipes connected in parallel on the fourth heat exchange flow path. The inlet end of the fourth heat exchange flow path is connected to one liquid distribution branch pipe B of the heat exchanger B, and the second branch pipe is connected to other liquid distribution branch pipes B of the heat exchanger B.

5. The heat pump cycle system according to claim 4, characterized in that: The heat exchanger A has three liquid distribution branches A. One liquid distribution branch A is connected to the inlet of the first heat exchange flow path, and one liquid distribution branch A is connected to the inlet of the third heat exchange flow path. The multiple first branches are connected in parallel to the remaining liquid distribution branches A. The heat exchanger B has three liquid distribution branches B. One liquid distribution branch B is connected to the inlet end of the sixth heat exchange flow path, and one liquid distribution branch B is connected to the inlet end of the fourth heat exchange flow path. The multiple second branches are connected in parallel to the remaining liquid distribution branches B.

6. The heat pump cycle system according to claim 3, characterized in that: The throttling device is a throttling valve.

7. The heat pump cycle system according to claim 3, characterized in that: Three-way valves are installed at the first node and the second node.

8. A method for operating a heat pump cycle system according to any one of claims 3 to 7, characterized in that, The process includes the following steps: A non-azeotropic working fluid is introduced into the heat pump cycle system; the compressor and throttling device are turned on; the system is started; the non-azeotropic working fluid sequentially passes through the compressor, heat exchanger A, condenser-side regenerator, throttling device, heat exchanger B, and evaporator-side regenerator before returning to the compressor; a portion of the high-boiling-point component in the liquid collector A of heat exchanger A enters the first heat exchange path of the condenser-side regenerator, and a portion enters the third heat exchange path of the intermediate regenerator; a portion of the high-boiling-point component in the liquid collector B of heat exchanger B enters the fourth heat exchange path of the intermediate regenerator, and a portion enters the sixth heat exchange path of the evaporator-side regenerator; the third heat exchange path of the intermediate regenerator... The heat exchange flow path exchanges heat with the fourth heat exchange flow path. The working fluid from the third heat exchange flow path merges with the working fluid from the first pipe A of heat exchanger A at the first node and then enters the first heat exchange flow path in the condenser-side regenerator. The first heat exchange flow path exchanges heat with the second heat exchange flow path. The outlets of the first and second heat exchange flow paths merge and then enter the throttling device together. The working fluid from the fourth heat exchange flow path merges with the working fluid from the first pipe B of heat exchanger B at the second node and then enters the fifth heat exchange flow path of the evaporator-side regenerator. The fifth heat exchange flow path exchanges heat with the sixth heat exchange flow path. The outlets of the fifth and sixth heat exchange flow paths merge and then enter the compressor together.

9. The operating method according to claim 8, characterized in that: The non-azeotropic working fluid is a binary non-azeotropic working fluid.

10. The operating method according to claim 8, characterized in that: The external cold source for heat exchanger A is air or water, and the external heat source for heat exchanger B is air or water.

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