Refrigeration and heating cycle system

Abstract

The present application relates to a kind of refrigeration heating cycle system, including external medium, first and second heat exchange mechanism, multiple compression mechanisms are arranged between first and second heat exchange mechanism, multiple expansion mechanisms, several intermediate heat exchange mechanisms and refrigerant pipeline;Each mechanism is connected into at least one circulation loop by refrigerant pipeline.In the same circulation loop, intermediate heat exchange mechanism is used to make refrigerant and external medium heat exchange;In adjacent two circulation loops, the refrigerant in two circulation loops is exchanged by intermediate heat exchange mechanism and simultaneously exchanges with external medium.Heat exchange mechanism is used to make refrigerant and external medium heat exchange;In adjacent two circulation loops, the refrigerant in two circulation loops is exchanged by intermediate heat exchange mechanism and simultaneously exchanges with external medium.The advantage is: improve the energy efficiency ratio of refrigeration heating cycle system and operation adaptability, break the mismatch bottleneck between constant evaporation / condensation temperature and variable temperature external medium in traditional single-stage cycle;It can seamlessly switch refrigeration, heating and cold and heat supply mode under single hardware architecture, realize the customized output of multiple temperature grade cold and heat, meet industrial and commercial demand.

Description

Technical Field

[0001] This invention relates to the field of refrigeration and heating equipment manufacturing technology, and in particular to a refrigeration and heating cycle system. Background Technology

[0002] Refrigeration and heating cycles are core technologies for energy conversion in modern industrial, commercial, and residential sectors. Traditional refrigeration and heating cycles (such as the widely used vapor compression refrigeration heat pump cycle) are typically based on a simple single-loop structure, mainly consisting of four basic processes: compression, condensation, throttling (expansion), and evaporation. In this cycle, the refrigerant dissipates heat to the heat sink in the condenser and absorbs heat from the heat source in the evaporator, thereby achieving heat transfer.

[0003] However, traditional cooling and heating cycles have technical defects or limitations: 1. In a traditional simple circulation loop, the condensation and evaporation temperatures of the refrigerant are almost constant, while the temperatures of the heat sink and heat source often vary considerably. This results in an inherent heat exchange mismatch in the refrigeration and heating cycle, leading to significant irreversible losses.

[0004] For example, the external medium from the heat source enters the evaporator at a higher temperature and exits at a lower temperature; similarly, the external medium enters the condenser at a lower temperature and exits at a higher temperature. In a traditional single-stage cycle, the constant evaporation / condensation temperature cannot achieve a good temperature match with the variable-temperature external medium. This temperature field mismatch leads to a large heat transfer temperature difference, resulting in significant irreversible thermodynamic losses and severely limiting the system's energy efficiency ratio. This is especially pronounced in operating conditions requiring large temperature differences for cooling or heating.

[0005] 2. An ideal compression process should be a continuously decreasing, infinitely multi-stage compression process accompanied by continuous cooling to minimize compression work. However, most existing practical compression processes are single-stage compressions, and even those employing multi-stage compression often lack effective interstage cooling measures. This leads to significant overheating during compression, causing the actual compression process to deviate greatly from the ideal isothermal compression process, increasing compressor power consumption, and reducing the overall system efficiency.

[0006] 3. In traditional cycles, high-pressure liquid refrigerant is depressurized through a throttling (expansion) valve. This process is a typical isenthalpic throttling, where the high-pressure potential energy is not effectively utilized to pre-cool the refrigerant, and the high-temperature heat energy is not effectively recovered for deep subcooling of the refrigerant. Especially under large temperature difference conditions, due to the lack of effective subcooling measures, the dryness of the refrigerant increases after throttling, leading to a decrease in the cooling capacity per unit mass of refrigerant and further reducing cooling and heating efficiency. Although some existing technologies employ multi-stage compression and intermediate gas extraction, the intermediate gas extraction is often limited to the energy circulation within the system, failing to break through the limitations of simple loops and unable to flexibly and efficiently exchange energy with external media at different temperatures.

[0007] 4. In a traditional simple loop, all energy and working fluid must flow in a fixed order and path. Once the operating conditions of a component change (such as load fluctuations or sudden changes in external medium temperature), the entire loop is easily impacted, and may even lead to system instability (such as surge), making it difficult to adapt to complex and ever-changing real-world application environments (such as scenarios that require multiple temperature gradients for heating and cooling, or large fluctuations in heating and cooling loads).

[0008] 5. In many industrial applications (such as chemical, pharmaceutical, and food processing) and high-end comfort air conditioning, it is often necessary to simultaneously provide multiple types of chilled water (such as chilled water, ice water), hot water (such as domestic hot water, process hot water, and high-temperature steam), or hot air at different temperatures. To meet these needs, existing technologies typically require multiple independent refrigeration units or heating equipment. This not only results in huge equipment investments and large floor space requirements, but also prevents the cascade utilization and complementarity of energy between the independent systems, leading to significant energy waste.

[0009] Therefore, this case arose. Summary of the Invention

[0010] To address the aforementioned problems, the present invention aims to provide a refrigeration and heating cycle system that significantly improves refrigeration and heating capacity and efficiency through comprehensive improvements and optimizations to the evaporation, condensation, compression, and throttling processes.

[0011] To achieve the above objectives, the technical solution of the present invention is as follows: A refrigeration and heating cycle system includes an external medium, a first heat exchange mechanism and a second heat exchange mechanism for exchanging heat between the refrigerant and the external medium for internal circulation, and a plurality of compression mechanisms, a plurality of expansion mechanisms, a plurality of intermediate heat exchange mechanisms and refrigerant pipelines arranged between the first heat exchange mechanism and the second heat exchange mechanism. Both the first heat exchange mechanism and the second heat exchange mechanism adopt one of the following: a heat release module, a heat absorption module, or a heat release / heat absorption switchable module; The refrigerant pipeline is used to connect several of the following mechanisms—the first heat exchange mechanism, the compression mechanism, the expansion mechanism, the intermediate heat exchange mechanism, and the second heat exchange mechanism—to form at least one circulation loop. In the same circulation loop, the compression mechanisms compress the refrigerant in the loop step by step, and the expansion mechanisms expand the refrigerant in the loop step by step. The intermediate heat exchange mechanism is used to enable the refrigerant to exchange heat with the external medium. In two adjacent circulation loops, the refrigerants in the two circulation loops exchange heat through the intermediate heat exchange mechanism and can simultaneously exchange heat with the external medium. The refrigerants in the two adjacent circulation loops can be the same type of refrigerant or different types of refrigerant. When there is only one circulation loop, the circulation loop includes a loop consisting of a first heat exchange mechanism, a compression mechanism, an expansion mechanism, an intermediate heat exchange mechanism, and a second heat exchange mechanism. The intermediate heat exchange mechanism is one of a heat release module, a heat absorption module, or a heat release / heat absorption switchable module. When there are two circulation loops, the circulation loop includes a loop consisting of a first heat exchange mechanism, a compression mechanism, an intermediate heat exchange mechanism, and an expansion mechanism, and a loop consisting of a second heat exchange mechanism, a compression mechanism, an intermediate heat exchange mechanism, and an expansion mechanism; the intermediate heat exchange mechanism is an internal heat exchange / external heat exchange composite module. When there are more than two circulation loops, the circulation loop includes a loop consisting of a first heat exchange mechanism, a compression mechanism, an intermediate heat exchange mechanism, and an expansion mechanism, a loop consisting of two adjacent intermediate heat exchange mechanisms, expansion mechanisms, and compression mechanisms, and a loop consisting of a second heat exchange mechanism, a compression mechanism, an intermediate heat exchange mechanism, and an expansion mechanism; the intermediate heat exchange mechanism is an internal heat exchange / external heat exchange composite module. Several external media flowing through the first heat exchanger and / or the second heat exchanger and / or the intermediate heat exchanger are connected in series and / or in parallel and / or in a mixed series-parallel connection.

[0012] Furthermore, several circulation loops are equipped with refrigerant discharge lines and refrigerant replenishment lines.

[0013] Furthermore, when there is only one circulation loop, the first heat exchange mechanism adopts a heat absorption module, the second heat exchange mechanism adopts a heat release module, there are n compression mechanisms, there are n expansion mechanisms, and the intermediate heat exchange mechanism adopts either a heat absorption module or a heat release module. There are n-1 intermediate heat exchange mechanisms, wherein one end of the k-th intermediate heat exchange mechanism is connected to the refrigerant flow path between the k-th compression mechanism and the (k+1)-th compression mechanism, and the other end is connected to the refrigerant flow path between the k-th expansion mechanism and the (k+1)-th expansion mechanism; the n compression mechanisms compress the refrigerant step by step from the first heat exchange mechanism to the second heat exchange mechanism, and the corresponding n expansion mechanisms expand the refrigerant step by step from the second heat exchange mechanism to the first heat exchange mechanism; The n is an integer not less than 2, and the k is an integer where 1≤k≤n-1.

[0014] Furthermore, the circulation loop is provided with an on / off valve, which is used to selectively open or close the refrigerant flow path through the first heat exchange mechanism, the compression mechanism, the expansion mechanism, the intermediate heat exchange mechanism, or the second heat exchange mechanism.

[0015] Furthermore, when there is only one circulation loop, the first heat exchange mechanism, the intermediate heat exchange mechanism, and the second heat exchange mechanism all adopt heat release / heat absorption switchable modules; there are n compression mechanisms, n expansion mechanisms, and n-1 intermediate heat exchange mechanisms, wherein one end of the kth intermediate heat exchange mechanism is connected to the refrigerant flow path between the kth and k+1th compression mechanisms, and the other end is connected to the refrigerant flow path between the kth and k+1th expansion mechanisms; one end of two adjacent heat release / heat absorption switchable modules is connected to the inlet and outlet of the compression mechanism at that end through a four-way valve; The n is an integer not less than 2, and the k is an integer where 1≤k≤n-1.

[0016] Furthermore, when there is only one circulation loop, the first heat exchange mechanism adopts a heat release / heat absorption switchable module, the second heat exchange mechanism adopts a heat release module, and the intermediate heat exchange mechanism adopts a heat release / heat absorption switchable module; there are n compression mechanisms, n expansion mechanisms, and n-1 intermediate heat exchange mechanisms, wherein one end of the kth intermediate heat exchange mechanism is connected to the refrigerant flow path between the kth and k+1th compression mechanisms, and the other end is connected to the refrigerant flow path between the kth and k+1th expansion mechanisms; one end of two adjacent heat release / heat absorption switchable modules is connected to the inlet and outlet of the compression mechanism at that end through a four-way valve, and a one-way valve is provided on the outlet side of the compression mechanism connected to the four-way valve; the circulation loop is provided with several on / off valves, which are used to selectively open or close the refrigerant flow path through the first heat exchange mechanism, compression mechanism, expansion mechanism, intermediate heat exchange mechanism, or second heat exchange mechanism.

[0017] Furthermore, when there is only one circulation loop, the first heat exchange mechanism adopts a heat absorption module, the second heat exchange mechanism adopts a heat release module, and the intermediate heat exchange mechanism adopts a heat release module. There are n compression mechanisms, n expansion mechanisms, and n-1 intermediate heat exchange mechanisms. The inlet of the kth intermediate heat exchange mechanism is connected to the outlet of the (k+1)th compression mechanism, the exhaust end is connected to the inlet of the kth compression mechanism through an exhaust pipe, and the liquid outlet end is connected to the refrigerant flow path between the kth expansion mechanism and the (k+1)th expansion mechanism. The n is an integer not less than 2, and the k is an integer where 1≤k≤n-1.

[0018] Furthermore, when there are multiple circulation loops, branches are provided in several circulation loops. The branches are located between the first heat exchange mechanism and the intermediate heat exchange mechanism and / or between two adjacent intermediate heat exchange mechanisms and / or between the intermediate heat exchange mechanism and the second heat exchange mechanism. The branch is equipped with an intermediate branch heat exchange mechanism, which adopts one of the following: a heat release module, a heat absorption module, or a heat release / heat absorption switchable module. The external medium flows through the intermediate branch heat exchange mechanism.

[0019] Furthermore, it includes a subcooler disposed on the inlet side and / or outlet side of the expansion mechanism, through which the external medium flows.

[0020] Furthermore, the circulation loop is equipped with a gas-liquid separator, which is used to separate the gaseous refrigerant and liquid refrigerant in the refrigerant. The liquid refrigerant enters the circulation loop in the original flow direction, while the gaseous refrigerant is diverted to the defrosting and de-icing mechanism. The circulation loop is equipped with an on / off valve, which is used to selectively open or close the refrigerant flow path through the first heat exchange mechanism, the compression mechanism, the expansion mechanism, the intermediate heat exchange mechanism, the second heat exchange mechanism, or the gas-liquid separator.

[0021] The advantages of this invention are: 1. Through flexible networked topology design, the energy efficiency ratio and operational adaptability of the refrigeration and heating cycle system are significantly improved, breaking the bottleneck of mismatch between constant evaporation / condensation temperature and variable temperature external medium in traditional single-stage cycles. Some implementations utilize multi-stage compression and expansion, combined with interstage heat exchange in the intermediate heat exchange mechanism, to ensure that the refrigerant's temperature change curve closely follows the temperature shift of the external medium, greatly reducing irreversible temperature difference losses during the heat exchange process.

[0022] 2. Through multi-stage compression and expansion, combined with interstage heat exchange in the intermediate heat exchange mechanism, and in some application scenarios, through the cooperation of "heat release / heat absorption switchable module" and / or four-way valve group and / or on / off valve, the system can seamlessly switch between cooling, heating and combined cooling and heating modes under a single hardware architecture, realize customized output of cooling and heating at various temperature levels, and meet complex industrial and commercial needs. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the single heat source / single heat sink circulation system in Example 1; Figure 2 This is a schematic diagram of the single heat source / single heat sink circulation system in Example 2; Figure 3 This is a schematic diagram of the single heat source / single heat sink circulation system in Example 3; Figure 4This is a schematic diagram of the circulation system with multiple heat sources and multiple heat sinks in Example 4; Figure 5 This is a schematic diagram of the cyclic system with two loops in Example 5; Figure 6 This is a schematic diagram of the direct expansion dual evaporator refrigeration system in Example 6; Figure 7 This is a schematic diagram of the dual-evaporator cooling water system in Example 7; Figure 8 This is a schematic diagram of a dual evaporator / dual condenser chilled / hot water system with a four-way switching valve in Example 8; Figure 9 This is a schematic diagram of the cold water system with two heat source fluids connected in parallel in Example 9; Figure 10 This is a schematic diagram of the cold water system with two heat source fluids connected in Example 10; Figure 11 This is a schematic diagram of the circulation system in Example 11 where the air source is combined with other heat sources; Figure 12 This is a schematic diagram of the combined air source and water heat source circulation system in Example 12, showing the first operating mode. Figure 13 This is a schematic diagram of the combined air source and water heat source circulation system in Example 12, showing the second operating mode. Figure 14 This is a schematic diagram of the combined air source and water heat source circulation system in Example 12, showing the third operating mode. Figure 15 This is a schematic diagram of the combined air source and water heat source circulation system in Example 12, showing the fourth operating mode. Figure 16 This is a schematic diagram of the combined air source and water heat source circulation system in Example 12, showing operation mode five. Figure 17 This is a schematic diagram of the combined air source and water heat source circulation system in Example 13. Compared with Example 12, Example 13 omits the gas-liquid separator. Figure 18 This is a schematic diagram of the direct expansion system capable of producing hot water in Example 14; the diagram shows operating mode one. Figure 19 This is a schematic diagram of the direct expansion system capable of producing hot water in Example 14; the diagram shows operating mode two. Figure 20 This is a schematic diagram of the direct expansion system capable of producing hot water in Example 14; the diagram shows operating mode three. Figure 21 This is a schematic diagram of the chiller system capable of producing hot water in Example 15; Figure 22This is a schematic diagram of the circulation system in Example 16 that can produce hot and cold water with a large temperature difference; Figure 23 This is a schematic diagram of the circulation system for producing hot water and cold water / ice with a large temperature difference in Example 17; Figure 24 This is a schematic diagram of the heat pump system used in the drying process in Example 18; Figure 25 This is a schematic diagram of a loop system with three loops in Example 19; Figure 26 This is a schematic diagram of a circulation system with three circulation loops in Example 20. This example is a variation of Example 19, in which an additional heat exchange mechanism is added to the circulation system. Detailed Implementation

[0024] The present invention will be further described in detail below with reference to embodiments. It should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", "length direction", etc. indicated by the accompanying drawings are based on the orientation or positional relationship shown in the drawings and are only for the convenience of describing the present invention and simplifying the description. They are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention.

[0025] Custom glossary: 1. Heat release module: The refrigerant undergoes condensation or cooling within this module, transferring heat to external media such as condensers and gas coolers from the heat sink.

[0026] 2. Heat absorption module: The refrigerant undergoes evaporation or heating within this module, extracting heat from an external medium, such as an evaporator or gas heater.

[0027] 3. Heat release / heat absorption switchable module: It can switch between two working states: heat release module and heat absorption module, such as condenser / evaporator (which can be an evaporator with high temperature stage circulation and switch to a condenser with low temperature stage circulation).

[0028] 4. Internal / External Heat Exchange Composite Module: It forms a high-temperature heat release channel and a low-temperature heat absorption channel isolated within a physical shell, enabling simultaneous heat release and absorption processes. This allows for heat exchange between the refrigerant in different circulation loops (internal heat exchange) and between the refrigerant and the external medium (external heat exchange), such as a composite heat exchanger between a condenser / evaporator and an evaporator, or a composite heat exchanger between a condenser / evaporator and a condenser.

[0029] The multiple compressors in the embodiments can be multiple independent compressors, or a single compressor with multi-stage compression functionality. The refrigerant can be a two-phase refrigerant or a gas. If it is a gas, there is no condensation or evaporation, so the evaporator is a gas heater and the condenser is a gas cooler. The refrigerant cycle can also be a transcritical cycle, such as a transcritical cycle using CO2 as the refrigerant. In this case, the evaporator remains an evaporator, and the condenser, without phase change, is a gas cooler.

[0030] The expansion mechanism in the embodiments uses an expansion valve or an expander. Example 1

[0031] like Figure 1 As shown, this embodiment is a single heat source / single heat sink circulation system, including evaporator 131, evaporator 132, condenser 111, condenser 112, first compressor 121, second compressor 122, third compressor 123, first expansion mechanism 141, second expansion mechanism 142, third expansion mechanism 143, first subcooler 151, second subcooler 152, and external media from the heat sink and external media from the heat source. Evaporator 131 corresponds to the first heat exchange mechanism, evaporator 132 corresponds to the second intermediate heat exchange mechanism, condenser 112 corresponds to the first intermediate heat exchange mechanism, and condenser 111 corresponds to the second heat exchange mechanism.

[0032] The refrigeration pipe R connects evaporator 131, evaporator 132, condenser 111, condenser 112, first compressor 121, second compressor 122, third compressor 123, first expansion mechanism 141, second expansion mechanism 142, third expansion mechanism 143, first subcooler 151, and second subcooler 152 into a loop. The right end of evaporator 132 is located between the second compressor 122 and the third compressor 123, and the left end is located between the second expansion mechanism 142 and the third expansion mechanism 143. The right section of condenser 112 is located between the second compressor 122 and the first compressor 121, and the left end is located between the second expansion mechanism 142 and the first expansion mechanism 141. The first subcooler 151 is located between the first expansion mechanism 141 and the condenser 111, and the second subcooler 152 is located between the second expansion mechanism 142 and the condenser 112.

[0033] The refrigerant output from evaporator 131 is compressed and pressurized by the third compressor 123, and then mixed with the refrigerant output from evaporator 132 before entering the second compressor 122. After being compressed and pressurized by the second compressor 122, part of it enters the condenser 112, and part of it is further compressed by the first compressor 121 before entering the condenser 111. The refrigerant output from the condenser 111 flows into the first subcooler 151 for subcooling. The refrigerant flowing out of the first subcooler 151 enters the first expansion mechanism 141. After being depressurized by the first expansion mechanism 141, the refrigerant mixes with the refrigerant flowing out of the condenser 112 and enters the second subcooler 152 for subcooling. The liquid refrigerant flowing out of the second subcooler 152 enters the second expansion mechanism 142. Part of the refrigerant flowing out of the second expansion mechanism 142 enters the evaporator 132 for evaporation and heat absorption, and the other part passes through the third expansion mechanism 143. The refrigerant flowing out of the third expansion mechanism enters the evaporator 131 for evaporation and heat absorption.

[0034] The low-temperature fluid HFI from the heat sink passes sequentially through the second subcooler 152, condenser 112, first subcooler 151 and condenser 111. After countercurrent heat exchange with the refrigerant, it is heated and becomes a high-temperature fluid HFO, which is then discharged back to the heat sink.

[0035] The high-temperature fluid CFI from the heat source passes through evaporator 132 and evaporator 131 in sequence. After countercurrent heat exchange with the refrigerant, it is cooled and becomes low-temperature fluid CFO, which is then discharged back to the heat source.

[0036] This embodiment utilizes multi-stage compression and expansion, combined with interstage heat exchange in the intermediate heat exchange mechanism, to ensure that the refrigerant's temperature change curve closely follows the temperature shift of the external medium. Simultaneously, interstage heat exchange improves heat utilization and significantly reduces irreversible temperature difference losses during the heat exchange process. The subcooler lowers the refrigerant temperature below the saturation condensation temperature, creating deep subcooling. This not only significantly reduces ineffective flash gas generated after throttling and increases the effective cooling capacity per unit mass of refrigerant, but also recovers potentially wasted high-pressure liquid sensible heat to raise the temperature of the external medium from the heat sink, further optimizing the energy gradient matching within the system and reducing overall cycle irreversible losses.

[0037] External medium fluid from the heat source flows from the high-temperature side evaporator 132 to the low-temperature side evaporator 131, while external fluid from the heat sink flows from the low-temperature side subcooler / condenser to the high-temperature side subcooler / condenser. This forms a strict counter-current heat exchange match with the refrigerant, minimizing the average heat transfer temperature difference between the hot and cold fluids throughout the heat exchange process. This effectively reduces the irreversible entropy increase caused by large temperature difference heat transfer, maximizes energy utilization efficiency, and enables the system to achieve maximum cooling and heating output with minimal compression work. Example 2

[0038] Similar to Example 1, such as Figure 2 As shown, this embodiment is a single heat source / single heat sink circulation system, differing from Embodiment 1 in the connection arrangement of the condenser 112. The system includes an evaporator 131, a condenser 111, a condenser 112, a first compressor 121, a second compressor 122, a first expansion mechanism 141, a second expansion mechanism 142, a first subcooler 151, a second subcooler 152, and external media from the heat sink and external media from the heat source. The evaporator 131 corresponds to the first heat exchange mechanism, the condenser 112 corresponds to the intermediate heat exchange mechanism, and the condenser 111 corresponds to the second heat exchange mechanism.

[0039] The refrigeration pipe R connects the evaporator 131, condenser 111, condenser 112, first compressor 121, second compressor 122, first expansion mechanism 141, second expansion mechanism 142, first subcooler 151, and second subcooler 152 into a loop. The inlet of condenser 112 is connected to the outlet of second compressor 122, its exhaust end is connected to the inlet of first compressor 121 via an exhaust pipe, and its liquid outlet end is connected to the refrigerant flow path between first expansion mechanism 141 and second expansion mechanism 142.

[0040] The refrigerant output from evaporator 131 is compressed and pressurized by second compressor 122. The pressurized refrigerant from second compressor 122 then enters condenser 112. The gaseous refrigerant output from condenser 112 is compressed by first compressor 121 and then enters condenser 111. The liquid refrigerant output from condenser 112 enters subcooler 152. The refrigerant output from condenser 111 flows into first subcooler 151 for subcooling. The refrigerant flowing out of first subcooler 151 enters first expansion mechanism 141. After being depressurized by first expansion mechanism 141, the refrigerant mixes with the refrigerant flowing out of condenser 112 and enters second subcooler 152 for further subcooling. The liquid refrigerant flowing out of second subcooler 152 enters second expansion mechanism 142 for further depressurization. The refrigerant flowing out of second expansion mechanism 142 enters evaporator 131 for evaporation and heat absorption.

[0041] The low-temperature fluid HFI from the heat sink passes sequentially through the second subcooler 152, condenser 112, first subcooler 151 and condenser 111. After countercurrent heat exchange with the refrigerant, it is heated and becomes a high-temperature fluid HFO, which is then discharged back to the heat sink.

[0042] The high-temperature fluid CFI from the heat source passes through the evaporator 131, where it exchanges heat with the refrigerant in a countercurrent flow and is cooled into a low-temperature fluid CFO, which is then discharged back to the heat source.

[0043] Figure 2All the refrigerant exiting the second compressor 122 passes through the condenser 112, where a portion becomes liquid refrigerant. The remaining gaseous refrigerant, without condensation, then enters the first compressor 121, thus ensuring that the superheat of the refrigerant entering the first compressor 121 is lower than that of the first compressor 121. Figure 1 In this case, it is beneficial to reduce the energy consumption of the first compressor 121. Of course, there are other methods to reduce the temperature of the refrigerant entering the first compressor 121, such as spraying liquid refrigerant between the first compressor 121 and the second compressor 122. Example 3

[0044] Similar to Example 1, such as Figure 3 As shown, this embodiment is a single heat source / single heat sink circulation system, including an evaporator 131, an evaporator 132, a condenser 111, a first compressor 121, a second compressor 122, a first expansion mechanism 141, a second expansion mechanism 142, and external media from the heat sink and external media from the heat source. The evaporator 131 corresponds to the first heat exchange mechanism, the evaporator 132 corresponds to the intermediate heat exchange mechanism, and the condenser 111 corresponds to the second heat exchange mechanism.

[0045] The refrigeration pipe R connects the evaporator 131, evaporator 132, condenser 111, first compressor 121, second compressor 122, first expansion mechanism 141, and second expansion mechanism 142 into a loop.

[0046] The refrigerant output from evaporator 131 is compressed and pressurized by the second compressor 122, and then mixed with the refrigerant output from evaporator 132 before entering the first compressor 121. After further compression by the first compressor 121, the refrigerant enters the condenser 111. The refrigerant output from condenser 111 is depressurized by the first expansion mechanism 141, and part of it is further expanded and depressurized by the second expansion mechanism 142 before entering the evaporator 131 for evaporation and heat absorption, while the other part enters the evaporator 131 for evaporation and heat absorption.

[0047] The low-temperature fluid from the heat sink passes through the HFI condenser 111, where it exchanges heat with the refrigerant in a countercurrent flow and is heated to become a high-temperature fluid HFO, which is then discharged back to the heat sink.

[0048] The high-temperature fluid CFI from the heat source passes through evaporator 132 and evaporator 131 in sequence. After countercurrent heat exchange with the refrigerant, it is cooled and becomes low-temperature fluid CFO, which is then discharged back to the heat source. Example 4

[0049] like Figure 4 As shown, the refrigerant circulation loop in this embodiment is the same as that in Embodiment 1, and will not be described again here. The difference is that this embodiment is a circulation system with multiple heat sources and multiple heat sinks, that is... Figure 1The middle part consists of a heat sink fluid with a large temperature difference (HFI-HFO) and a heat source fluid with a large temperature difference (CFI-CFO). Figure 4 The middle part consists of multiple independent heat sink fluids (1HFI-1HFO, 2HFI-2HFO) and multiple independent heat source fluids (1CFI-1CFO, 2CFI-2CFO).

[0050] The low-temperature fluid 1HFI from the heat sink passes sequentially through the first subcooler 151 and the condenser 111, and after countercurrent heat exchange with the refrigerant, it is heated and becomes a high-temperature fluid 1HFO, which is then discharged back to the heat sink. The low-temperature fluid 2HFI from the heat sink passes sequentially through the second subcooler 152 and the condenser 112, and after countercurrent heat exchange with the refrigerant, it is heated and becomes a high-temperature fluid 2HFO, which is then discharged back to the heat sink.

[0051] The high-temperature fluid 2CFI from the heat source passes through the evaporator 132, where it exchanges heat with the refrigerant in a counter-current flow and is cooled into a low-temperature fluid 2CFO, which is then discharged back to the heat source. The high-temperature fluid 1CFI from the heat source passes through the evaporator 131, where it exchanges heat with the refrigerant in a counter-current flow and is cooled into a low-temperature fluid 1CFO, which is then discharged back to the heat source. Example 5

[0052] like Figure 5 As shown, Embodiment 5 proposes a circulating system with two loops, including a first compressor 121, a second compressor 122, a third compressor 123, a condenser 111, a combined heat exchanger 161 for evaporator / condenser and condenser, a first expansion mechanism 141, a second expansion mechanism 142, and an evaporator 131. The condenser 111 corresponds to the second heat exchanger, the evaporator 131 corresponds to the first heat exchanger, and the combined heat exchanger 161 for evaporator / condenser and condenser corresponds to an intermediate heat exchanger.

[0053] The refrigerant line R connects the evaporator 131, the third compressor 123, the condenser side of the composite heat exchanger 161, and the second expansion mechanism 142 to form a first circulation loop. The refrigerant line R also connects the evaporator side of the composite heat exchanger 161, the second compressor 122, the first compressor 121, the condenser 111, and the first expansion mechanism 141 to form a second circulation loop. The second circulation loop also includes a second vapor discharge line ZQ2 connected to the outlet of the second compressor 122, a first vapor discharge line ZQ1 connected to the outlet of the first compressor 121, and a refrigerant replenishment line BR connected to the inlet of the evaporator side of the composite heat exchanger 161.

[0054] The high-temperature fluid CFI from the heat source enters the evaporator 131, is cooled into a low-temperature fluid CFO, and then discharged back to the heat source. The refrigerant evaporates in the evaporator 131 to produce a low-pressure gaseous refrigerant. The low-pressure gaseous refrigerant is compressed by the third compressor 123 and then enters the condenser side of the composite heat exchanger 161 for heat exchange and condensation. Then it returns to the evaporator 131 through the second expansion mechanism 142. The low-temperature fluid 1HFI from the heat sink flows through the condenser side of the composite heat exchanger 161 and is heated, becoming a high-temperature fluid 1HFO, which is then discharged.

[0055] Refrigerant water enters the evaporator side of the composite heat exchanger 161 through the refrigerant replenishment pipeline BR to generate steam. After the steam is pressurized by the second compressor 122, part of it is discharged through the second steam discharge pipeline ZQ2, and the other part of the steam enters the first compressor 121 for further pressurization. After being pressurized by the first compressor 121, part of the steam is discharged through the first steam discharge pipeline ZQ1, and the other part of the steam is condensed by the condenser 111, which turns the low-temperature fluid 2HFI flowing through the heat sink into a high-temperature fluid 2HFO. The steam output from the condenser 111 passes through the first expansion mechanism 141 and enters the evaporator side of the composite heat exchanger 161 together with the replenishment water.

[0056] This embodiment differs from embodiments 1 to 4 in that it forms two circulation loops by setting up a composite heat exchanger 161. The main purposes are threefold: firstly, different refrigerants are required for different temperatures; secondly, for oil-lubricated compressors, the oil return process can be simplified; and thirdly, for situations requiring direct steam discharge, the composite heat exchanger 161 can separate the closed-loop system from the open-loop system.

[0057] It is important to note that the refrigerants in the two circulation loops can be the same type of refrigerant or different types of refrigerant. Example 6

[0058] like Figure 6As shown, this embodiment proposes a direct expansion dual evaporator refrigeration system for large temperature difference refrigeration or refrigeration dehumidification. Similar to Embodiment 3, it includes an evaporator 131, an evaporator 132, a condenser 111, a first compressor 121, a second compressor 122, a first expansion mechanism 141, and a second expansion mechanism 142. However, unlike Embodiment 3, the heat sink and heat source in this embodiment do not use a fluid medium; instead, a fan is used to circulate air, allowing direct heat exchange with the refrigerant. The heat sink includes a first outer shell WK1 and a first fan FJ1, with the first fan FJ1 and condenser 111 fixed to the first outer shell WK1. The heat source includes a second outer shell WK2 and a second fan FJ2, with the second fan FJ2, evaporator 131, and evaporator 132 fixed to the second outer shell WK2. Evaporator 131 corresponds to the first heat exchange mechanism, evaporator 132 corresponds to the intermediate heat exchange mechanism, and condenser 111 corresponds to the second heat exchange mechanism.

[0059] The refrigeration pipe R connects the evaporator 131, evaporator 132, condenser 111, first compressor 121, second compressor 122, first expansion mechanism 141, and second expansion mechanism 142 into a loop.

[0060] The refrigerant output from evaporator 131 is compressed and pressurized by the second compressor 122, and then mixed with the refrigerant output from evaporator 132 before entering the first compressor 121. After further compression by the first compressor 121, the refrigerant enters the condenser 111. The refrigerant output from condenser 111 is depressurized by the first expansion mechanism 141, and part of it is further expanded and depressurized by the second expansion mechanism 142 before entering the evaporator 131 for evaporation and heat absorption, while the other part enters the evaporator 131 for evaporation and heat absorption.

[0061] In the heat source, the second fan FJ2 drives air FA to pass through evaporator 132 and evaporator 131 in sequence, where it is cooled in stages or dehumidified before being output. In the heat sink, the first fan FJ1 drives air FA to pass through condenser 111, where it is heated before being output. Example 7

[0062] This embodiment proposes a dual-evaporator cooling water system. The circulation loop in this embodiment is the same as that in Embodiment 6, and will not be described again here. The difference is that in Embodiment 6, the air is cooled by an evaporator, while in this embodiment, the water is cooled by an evaporator, i.e., the external medium is water. Figure 7 As shown, water, driven by pump P, enters the air / water heat exchanger WAH to cool the air by a large temperature difference. The air is also driven by fan FJ. After passing through the air / water heat exchanger WAH, the water becomes hot and continues to be cooled in stages by pump P, passing through evaporator 132 and evaporator 131 in sequence. Example 8

[0063] like Figure 8As shown, this embodiment proposes a dual evaporator / dual condenser chilled / hot water system with a four-way switching valve, including condenser / evaporator 1231, condenser / evaporator 1232, condenser / evaporator 1233, four-way valve STV1, four-way valve STV2, first compressor 121, second compressor 122, first expansion mechanism 141, and second expansion mechanism 142. The right end of condenser / evaporator 1231 is connected to the first port of four-way valve STV2, the right end of condenser / evaporator 1232 is connected to the third port of four-way valve STV2, the outlet of second compressor 122 is connected to the fourth port of four-way valve STV2, and the inlet of second compressor 122 is connected to the second port of four-way valve STV2. The right end of condenser / evaporator 1232 is connected to the first port of four-way valve STV1, the right end of condenser / evaporator 1233 is connected to the third port of four-way valve STV1, the outlet of first compressor 121 is connected to the fourth port of four-way valve STV1, and the inlet of first compressor 121 is connected to the second port of four-way valve STV1. First expansion mechanism 141 is disposed between the left ends of condenser / evaporator 1232 and condenser / evaporator 1233, and first expansion mechanism 142 is disposed between the left ends of condenser / evaporator 1232 and condenser / evaporator 1231. The external medium portion of this embodiment is the same as in embodiment 7. Condenser / evaporator 1231 corresponds to the first heat exchange mechanism, condenser / evaporator 1232 corresponds to the intermediate heat exchange mechanism, and condenser / evaporator 1233 corresponds to the second heat exchange mechanism.

[0064] by Figure 8 As shown by the four-way valve, condenser / evaporator 1231 and condenser / evaporator 1232 are both condensers, and condenser / evaporator 1233 is an evaporator. The circulation system in the diagram can heat the external medium water, thereby raising the air temperature. By switching the four-way valve, the... Figure 8 The loop direction is transformed into Figure 7 The circulation direction within the system enables cooling of the external water medium. Example 9

[0065] like Figure 9 As shown, this embodiment is a schematic diagram of a cold water system with two heat source fluids connected in parallel. The configuration of its circulation loop is the same as in Embodiment 7, so it will not be described again. The difference from Embodiment 7 is that... Figure 7 In the middle, a stream of water is cooled as it passes through evaporator 132 and evaporator 131 in sequence. Figure 9In this system, all the water passes through evaporator 132 to become medium-temperature water (MW). A portion of the medium-temperature water (MW) discharged from evaporator 132 enters evaporator 131 for further cooling to become low-temperature water (LW), while the remaining portion of the medium-temperature water (MW) does not pass through evaporator 131. The low-temperature water (LW) is sent to the humidity control unit (DEH) for dehumidifying the air, while the medium-temperature water (MW) is sent to the temperature control unit (TAD), such as the air handling terminal, for cooling the air. The water from the humidity control unit (DEH) and the temperature control unit (TAD) mixes and is then recirculated back to evaporator 132 by pump P. This system is particularly suitable for the currently popular dual-source (i.e., medium-temperature water and low-temperature water) independent temperature and humidity control system (DEH handles humidity, TAD handles temperature), which currently achieves dual-source cooling through two independent chiller units. Figure 9 The intermediate system can replace the current two chiller units, while also making the production of low-temperature chilled water more efficient because the refrigerant entering the evaporator 131 is subcooled. Figure 9 The condenser in the system can be air-cooled or water-cooled. Example 10

[0066] like Figure 10 As shown, this embodiment is a schematic diagram of a chilled water system with two heat source fluids connected in parallel. The circulation loop is set up based on embodiment 7 by adding a gas-liquid separator FL. The inlet of the gas-liquid separator FL is connected to the outlet of the condenser 111 through the refrigerant pipeline R. The liquid outlet of the gas-liquid separator FL is connected to the inlet of the first expansion mechanism 141. The exhaust end of the gas-liquid separator FL is connected to the outlet of the evaporator 131 and the inlet of the second compressor 122 through an exhaust pipe. An on / off valve V1 is provided on the exhaust pipe. At the same time, an on / off valve V2 is provided on the pipeline between the outlet of the evaporator 131 and the inlet of the second compressor 122.

[0067] In this embodiment, evaporator 132 is used to produce cold water at a higher temperature, i.e., to cool water W1. Evaporator 131 is used to produce ice or an ice-water mixture, i.e., water W2 enters evaporator 131 under the drive of pump P and becomes subcooled water or ice flows into water tank WT. Water tank WT discharges ice or ice-water mixture WO to the user who needs cooling, and returns heated cold water WI from the user.

[0068] This embodiment employs a hot gas bypass reverse circulation method to achieve automatic ice melting in the evaporator 131. When ice removal is detected, the control system opens the on / off valve V1 and closes the on / off valve V2, simultaneously stopping the second compressor 122. At this time, the medium-temperature, high-pressure gaseous refrigerant from the condenser 111 undergoes gas-liquid separation via the gas-liquid separator FL. The liquid refrigerant enters the evaporator 132 after passing through the first expansion mechanism 141, while the gaseous refrigerant directly enters the evaporator 131 through the exhaust pipe. Inside the evaporator 131, the gaseous refrigerant releases heat to the ice layer or subcooled water outside the pipe, condensing itself into liquid, thereby rapidly melting the ice layer. After ice removal is complete, the system closes the on / off valve V1, opens the on / off valve V2, and restarts the second compressor 122, immediately restoring the refrigeration and ice-making operation. This method requires no external auxiliary heat source, utilizing the system's waste heat to achieve energy-saving optimization in the ice melting process. Example 11

[0069] like Figure 11 As shown, this embodiment is a circulation system combining an air source and other heat sources. Its circulation system is the same as in Embodiment 10, the difference being the arrangement of the external medium. Figure 10 Both evaporators are used for cooling water. In this embodiment, evaporator 131 is used for cooling air, hence the addition of a fan FJ and a casing WK. Evaporator 132 is used for cooling water. The refrigerant flowing through the two evaporators absorbs heat from the air and water, undergoes multi-stage compression, and then enters condenser 111. The external medium passing through condenser 111 can be water or air, used to produce hot water and hot air. Details of the external medium at condenser 111 are not shown in the figure.

[0070] This embodiment is designed for heating purposes. Evaporator 131 extracts heat from the air, while evaporator 132 can extract heat from other heat sources such as solar water heaters or industrial wastewater, thus forming a heat pump that combines air source and other heat sources. The defrosting process of this system is the same as in Embodiment 10, and will not be described in detail here. Example 12

[0071] like Figures 12 to 16As shown, this embodiment is a combined air source and water heat source circulation system, similar to Embodiment 10. This embodiment includes an evaporator 131, an evaporator 132, a condenser 111, a first compressor 121, a second compressor 122, a first expansion mechanism 141, a second expansion mechanism 142, and a gas-liquid separator FL. Evaporator 131 corresponds to the first heat exchange mechanism, evaporator 132 corresponds to the intermediate heat exchange mechanism, and condenser 111 corresponds to the second heat exchange mechanism. A refrigeration pipe R connects the evaporator 131, evaporator 132, condenser 111, first compressor 121, second compressor 122, first expansion mechanism 141, and second expansion mechanism 142 into a circulation loop. The exhaust end of the gas-liquid separator FL is connected to the outlet of evaporator 131 and the inlet of second compressor 122 via an exhaust pipe, and an on / off valve V1 is installed on the exhaust pipe. Simultaneously, an on / off valve V2 is installed on the pipe between the outlet of evaporator 131 and the inlet of second compressor 122.

[0072] Unlike Embodiment 10, the circulation loop in this embodiment includes branch pipe ab, branch pipe ac, on / off valve V3, on / off valve V4, and on / off valve V5. On / off valve V3 is located on the outlet side of evaporator 132. Point a of branch pipe ab is located between on / off valve V3 and the outlet side of evaporator 132, and point b of branch pipe ab is located between on / off valve V2 and the inlet of second compressor 122. Point a of branch pipe ac is the same as point a of branch pipe ab, and point c of branch pipe ac is located on the inlet side of evaporator 131. On / off valve V4 is installed on branch pipe ac, and on / off valve V5 is installed on branch pipe ab.

[0073] Figure 12 In the first operating mode of Example 12, on-off valves V1, V4, and V5 are closed, while on-off valves V2 and V3 are open. Fan FJ operates, cooling air through evaporator 131 to form cold air. Pump P operates, cooling water through evaporator 131 to form low-temperature water. A portion of the refrigerant absorbs heat from the air through evaporator 131 and enters the second compressor 122. Another portion of the refrigerant absorbs heat from the water through evaporator 132 and mixes with the refrigerant output from the second compressor 122, both entering the first compressor 121. After compression, the mixture enters the condenser 111 to release heat. Then, through the first expansion mechanism 141, a portion returns to the evaporator 132, while the other portion returns to the evaporator 131 after passing through the second expansion mechanism 142.

[0074] Figure 13In the second operating mode of Example 12, on-off valves V1, V4, and V5 are closed, while on-off valves V2 and V3 are open. In the first operating mode, the cooling water at the evaporator 132 may freeze. This freezing can be eliminated in the second operating mode. Heat is extracted from the air through the evaporator 131. By increasing the pressure of the second compressor 122 and increasing the opening of the second expansion mechanism 142, part of the high-temperature refrigerant from the second compressor 122 enters the first compressor 121, while the other part enters the evaporator 132 in reverse to melt the ice. The low-temperature refrigerant from the evaporator 132 merges with the low-temperature refrigerant from the first expansion mechanism 141 and returns to the evaporator 131 through the second expansion mechanism 142.

[0075] Figure 14 In the third operating mode of Example 12, on-off valves V1, V3, and V5 are closed, while on-off valves V2 and V4 are open. In the first operating mode, the cooling water at the evaporator 132 may freeze. This freezing can be eliminated in operating mode three, although the freezing elimination effect is less than in operating mode two. The evaporator 131 absorbs heat from the air, undergoes two stages of compression (second compressor 122 and first compressor 121), and then releases heat in the condenser. The medium-temperature, high-pressure refrigerant exiting the condenser expands and depressurizes through the first expansion mechanism 141. Part of it enters the evaporator 132, and part enters the second expansion mechanism 142. Because the evaporator 132 is frozen, the refrigerant entering evaporator 132 cannot absorb heat; instead, it heats the evaporator 132 to melt the ice. The refrigerant exiting evaporator 132 passes through branch pipe ac and mixes with the refrigerant exiting the second expansion mechanism 142 before returning to the evaporator 131.

[0076] Figure 15 This is the fourth operating mode of Example 12. In this mode, on-off valves V2, V4, and V3 are closed, while on-off valves V1 and V5 are open. In operating modes one through three, frost may form on evaporator 131. Operating mode four is used for defrosting evaporator 131. The refrigerant output from evaporator 132 undergoes two stages of compression via the second compressor 122 and the first compressor 121 before entering the condenser to release heat. The medium-temperature, high-pressure refrigerant output from the condenser passes through the gas-liquid separator FL. The gaseous refrigerant is guided through the exhaust pipe into evaporator 131. At this point, the temperature of the gaseous refrigerant is higher than that of evaporator 131, so defrosting can occur. The liquid refrigerant returns to evaporator 132 after being depressurized by the first expansion mechanism 141.

[0077] Figure 16This is operating mode five of Example 12. In this mode, on-off valves V1, V4, and V5 are closed, while on-off valves V2 and V3 are open. Unlike operating mode one, in operating mode one, evaporator 132 extracts heat from the water. In operating mode five, the water heat source is disconnected, and the air heat source flows sequentially through evaporator 132 and evaporator 131. Therefore, both evaporator 132 and evaporator 131 extract heat from the air. Example 13

[0078] like Figure 17 As shown, this embodiment proposes a direct expansion multi-split air conditioning system with hot water and dual heat exchangers, whose circulation loop is connected to... Figure 12 Similarly, but the gas-liquid separator FL is eliminated, and one end of the on-off valve V1 is connected to the evaporator 131 and the on-off valve V2 through a pipeline, and the other end of the on-off valve V1 is connected to the outlet of the first compressor 121 and the condenser 111.

[0079] In this system, operating modes one through three and operating mode five are the same as in Example 12. When operating mode four is in operation, on-off valves V2, V4, and V3 are closed, while on-off valves V1 and V5 are open. The refrigerant output from evaporator 132 is compressed in two stages by the second compressor 122 and the first compressor 121. Part of it enters condenser 111 to release heat, and part of it enters evaporator 131 for defrosting. The medium-temperature, high-pressure refrigerant output from the condenser is depressurized by the first expansion mechanism 141 and then returns to evaporator 132. Example 14

[0080] like Figure 18 As shown, this embodiment is a direct expansion system capable of producing hot water, comprising a condenser 111, a condenser / evaporator 1231, a condenser / evaporator 1232, a first compressor 121, a second compressor 122, a first expansion mechanism 141, a second expansion mechanism 142, a four-way valve STV, an on / off valve V1, an on / off valve V2, and a one-way valve DXV. The condenser 111 corresponds to the second heat exchange mechanism, the condenser / evaporator 1231 corresponds to the first heat exchange mechanism, and the condenser / evaporator 1232 corresponds to an intermediate heat exchange mechanism.

[0081] The refrigeration piping R connects condenser 111, condenser / evaporator 1231, condenser / evaporator 1232, first compressor 121, second compressor 122, first expansion mechanism 141, second expansion mechanism 142, four-way valve STV, on-off valve V1, on-off valve V2, and one-way valve DXV into a loop. The first port of the four-way valve STV is connected to one end of condenser / evaporator 1231, and the third port is connected to one end of condenser / evaporator 1232. The other ends of condenser / evaporator 1232 and condenser / evaporator 1231 are respectively connected to the two ends of the second expansion mechanism 142. The fourth port of the four-way valve STV is connected to the outlet side of the second compressor 122 via one-way valve DXV, and the third port is connected to the inlet side of the second compressor 122. On-off valve V1 is located on the bypass of the first compressor 121, and on-off valve V2 is located between the second expansion mechanism 142 and condenser / evaporator 1232.

[0082] Fans (FJ1 and FJ2) are installed at both condenser / evaporator 1231 and condenser / evaporator 1232. These fans direct airflow through condenser / evaporator 1231 and condenser / evaporator 1232 to achieve heat exchange. Fan FJ1 at condenser / evaporator 1231 is located indoors, while fan FJ2 at condenser / evaporator 1232 is located outdoors. A water pipe is installed at the condenser to heat cold water WI to obtain hot water WO.

[0083] Figure 18 In the first operating mode of this system, the first and fourth ports of the four-way valve STV are connected, and the second and third ports are connected. In this mode, condenser / evaporator 1231 is the condenser, condenser / evaporator 1232 is the evaporator, and the system is in indoor heating mode.

[0084] The high-temperature, high-pressure gaseous refrigerant output from the second compressor 122 passes through the one-way valve DXV. A portion of it enters the four-way valve STV through the fourth port, then exits through the first port of the four-way valve STV and enters the condenser 1231. The gaseous refrigerant condenses and releases heat, becoming liquid, and is then discharged from the condenser 1231. The fan FJ1 drives the indoor air RA through the condenser 1231, where it is heated and delivered to the room. The liquid refrigerant discharged from the condenser 1231 passes through the second expansion mechanism 142, then through the on / off valve V2, mixing with the refrigerant from the outlet of the first expansion mechanism 141 before entering the evaporator 1232. The refrigerant evaporates and absorbs heat, becoming gaseous. The second fan drives the outdoor air FR into the evaporator 1232, where it exchanges heat with the refrigerant, is cooled, and is discharged. The refrigerant output from the evaporator 1232 enters the second compressor 122 through the third and second ports of the four-way valve STV. Another portion of the gaseous refrigerant output from the second compressor 122, passing through the one-way valve DXV, enters the first compressor 121. After further compression in the first compressor 121, it enters the condenser 111, where it condenses and releases heat to become liquid. Then, after passing through the first expansion mechanism 141, it mixes with the liquid refrigerant from the second expansion mechanism 142 and enters the evaporator 1232. The condenser 111 heats water, specifically heating the lower-temperature water WI to a higher-temperature water WO before discharging it. When the temperature of the gaseous refrigerant discharged from the second compressor 122 is sufficient to meet the requirements for heating the water, the first compressor 121 shuts off, the bypass valve V1 opens, and the gaseous refrigerant bypasses the first compressor 121 and enters the condenser 111.

[0085] Figure 19 In the second operating mode of this system, the first and second ports of the four-way valve STV are connected, and the fourth and third ports are connected. In this mode, condenser / evaporator 1231 is the evaporator, condenser / evaporator 1232 is the condenser, and the system is in indoor cooling mode.

[0086] Low-pressure liquid refrigerant evaporates into a gaseous state in evaporator 1231, then enters the first and second ports of the four-way valve STV and exits into the inlet of the second compressor 122. After being compressed and pressurized by the second compressor 122, it passes through the one-way valve DXV and splits into two paths. One path enters the condenser 1232 through the fourth and third ports of the four-way valve STV. After being condensed in the condenser 1232, it mixes with the refrigerant from the first expansion mechanism 141, then passes through the open on / off valve V2 to the second expansion mechanism 142 for expansion and depressurization, before entering the evaporator 1231. The condenser heats the outdoor air, while the evaporator cools the indoor air. The other path of refrigerant from the one-way valve DXV enters the first compressor 121, is pressurized, and then enters the condenser 111 to heat water. After passing through the first expansion mechanism 141 for expansion and depressurization, it mixes with the refrigerant discharged from the condenser 1232. In this mode, the on / off valve V1 is closed. Of course, the on / off valve V1 can also be opened to turn the first compressor 121 on and off.

[0087] Figure 20 In the third operating mode of this system, the first and second ports of the four-way valve STV are connected, and the fourth and third ports are connected. In this mode, the on-off valves V1 and V2 are closed, the condenser / evaporator 1232 is the evaporator, and the system is in independent hot water production mode, that is, when the room does not need cooling or heating, it independently produces hot water.

[0088] At this point, the entire system is the traditional simple circulation loop mentioned in the background technology. After the liquid refrigerant absorbs heat and evaporates in the evaporator 1232, it enters the first compressor 121 through the third and fourth ports of the four-way valve. After being compressed and pressurized by the first compressor 121, it enters the condenser 111 to be condensed, heating the hot water. Then, it returns to the evaporator 1232 through the first expansion mechanism 141.

[0089] This embodiment provides a direct expansion system (including a room air conditioner) that can produce hot water while heating and cooling. That is, it can recover waste heat during cooling and meet the hot water demand during heating. At the same time, it can independently produce hot water when heating and cooling are not needed. The system can guarantee the quality of hot water under all circumstances. Example 15

[0090] like Figure 21 This embodiment is a chiller system capable of producing hot water. The circulation loop of this system is similar to that of Embodiment 3, except for the arrangement of the external medium. The system includes an evaporator 131, a condenser 111, a condenser 112, a first compressor 121, a second compressor 122, a first expansion mechanism 141, a second expansion mechanism 142, and a first subcooler 151. The evaporator 131 corresponds to the first heat exchange mechanism, the condenser 112 corresponds to the intermediate heat exchange mechanism, and the condenser 111 corresponds to the second heat exchange mechanism.

[0091] The refrigeration pipe R connects the evaporator 131, condenser 111, condenser 112, first compressor 121, second compressor 122, first expansion mechanism 141, second expansion mechanism 142, and first subcooler 151 into a loop. The refrigerant circulation process is not described in detail.

[0092] In the heat source, chilled water LDW is produced by using evaporator 131. Water flows through evaporator 131 and is cooled down by absorbing heat, thus forming chilled water, such as 7°C chilled water.

[0093] In the heat sink, one path utilizes condenser 112 to heat the cooling water, such as... Figure 21 The cooling water LQW is heated by the pump P1, passes through the condenser 112, is cooled by the cooling tower LQT, and then returns to the condenser 112.

[0094] Another route is to produce hot water HW, which is driven to the heat user RYH by pump P2. The cooled return water is first preheated by subcooler 151 and then enters condenser 111 for heating. Example 16

[0095] like Figure 22 As shown, this embodiment is a typical heating and cooling system for a pharmaceutical reactor. The reactor generally requires steam heating at around 100-120℃. The heating is maintained at a certain temperature to produce organic vapor. The organic vapor condenses to produce condensate product. Condensation requires a cold source of -10℃ to 30℃. Since the organic vapor is discontinuous while the heating is continuous, a hot water tank is needed for heat storage.

[0096] The layout of the circulation loop in this embodiment is similar to that in Embodiment 1, except for the arrangement of the external medium. The system includes a first compressor 121, a second compressor 122, a third compressor 123, a fourth compressor 124, a condenser 111, a condenser 112, an evaporator 131, an evaporator 132, an evaporator 133, a first expansion mechanism 141, a second expansion mechanism 142, a third expansion mechanism 143, a fourth expansion mechanism 144, and a subcooler 151. Figure 1 The refrigerant piping connects the above components into a loop. Evaporator 131 is equivalent to the first heat exchange mechanism, condenser 112 is equivalent to the first intermediate heat exchange mechanism, evaporator 133 is equivalent to the second intermediate heat exchange mechanism, evaporator 132 is equivalent to the third intermediate heat exchange mechanism, and condenser 111 is the second heat exchange mechanism.

[0097] In the heat source, the cold water CW is driven by pump P2 and passes through evaporator 133, evaporator 132 and evaporator 131 in sequence to be cooled step by step. Then it is heated by organic vapor cooler LQ and returns to evaporator 133. The organic coolant EQ is cooled by organic vapor cooler LQ and then discharged.

[0098] In the heat sink, low-temperature hot water HW from the hot water tank WT, driven by pump P1, passes sequentially through the regenerator RH (recovering heat from organic steam), condenser 112, subcooler 151, and condenser 111, and is heated to approximately 80°C before being sent back to the hot water tank WT. The heat from the hot water tank WT serves as the heat source for the steam heat pump ZHP, generating steam ZQ which is supplied to the reactor FH. The organic steam discharged from the reactor FH passes through the regenerator RH and the organic steam cooler LQ before being discharged. Example 17

[0099] like Figure 23 As shown, this embodiment is a circulating system for producing hot water and cold water / ice with a large temperature difference. The layout of the circulation loop of this system is similar to that of Embodiment 16, the difference being the setting of the external medium. The evaporator 133 is replaced with a condenser 113, and the evaporator 132 is replaced with an economizer JJQ, which is equivalent to an intermediate heat exchange mechanism. The economizer JJQ is used to achieve gas-liquid separation and subcooling of the refrigerant, so that a portion of the refrigerant absorbs heat and evaporates before entering the third compressor 123 (for this portion of the refrigerant, the economizer is an evaporator), while the other portion of the liquid refrigerant is subcooled before entering the evaporator 131 (for this portion of the refrigerant, the economizer is a condenser).

[0100] In the heat source, external medium water CW produces cold water through evaporator 131 and stores it in water tank WT2.

[0101] In the heat sink, the external medium water HW passes through condenser 113, subcooler 152, condenser 112, subcooler 151, and condenser 111 in sequence before entering the water tank WT1 for hot water storage.

[0102] This system is suitable for applications requiring large temperature differences in hot water, cold water, or ice / cold water. It is easy to centrally configure and enables long-distance transport of hot water, cold water, or ice. Furthermore, the large temperature difference or the use of ice facilitates high-density energy storage. A typical application of this system is a rotary low-temperature dehumidification system: cold water or ice is used to lower the temperature of the air being dehumidified by the rotary wheel, while hot water is used for wheel regeneration. Compared to existing rotary systems (which typically use 7°C cold water and high-temperature steam above 120°C), this system significantly improves energy efficiency, achieving energy savings of over 60% under typical conditions. Combined with energy storage technology, energy costs are further reduced to approximately 10% of existing systems.

[0103] Figure 23The plan incorporates energy storage: hot water is produced using off-peak electricity and stored in WT1, and ice is produced and stored in WT2; the stored cold and heat are used during off-peak hours. Furthermore, the system can operate directly during off-peak hours to fully utilize equipment efficiency. Example 18

[0104] like Figure 24 As shown, this embodiment is a direct expansion system for simultaneous cooling and heating. The circulation loop of this system is similar to that of Embodiment 1, but the external medium has been modified. This embodiment uses a drying tower (GCT) as an example, where the heat source fluid is the high-temperature exhaust gas from the drying tower, and the heat sink fluid is the low-temperature inlet gas from the drying tower. Of course, this system has wide applicability and can also utilize waste heat from industrial equipment (such as waste gas or waste liquid) as a heat source to produce hot water or hot air.

[0105] On the heat source side: the medium-temperature, high-humidity gas MA discharged from the drying tower GCT passes through evaporators 132 and 131 sequentially according to the temperature gradient of the circulation loop, where it is cooled and dehumidified, transforming into low-temperature, dry gas CA. This gas then passes through the heat recovery unit SR, where its temperature continues to decrease. This process not only deeply recovers waste heat but also achieves energy balance for the heat pump system.

[0106] Heat sink side: The low-temperature dry gas after passing through SR then enters subcooler 152, condenser 112, subcooler 151 and condenser 111 in sequence, absorbs the heat released by the refrigerant, and is heated to become high-temperature dry gas HA, which then enters drying tower GCT. Example 19

[0107] like Figure 25 As shown, this embodiment is a circulating system with three circulation loops. Similar to embodiment 5, multiple circulation loops are formed by setting up a composite heat exchanger. The main purposes are threefold: firstly, different refrigerants are required for different temperatures; secondly, for oil-lubricated compressors, oil return processing can be simplified; and thirdly, for situations requiring direct steam discharge, the composite heat exchanger can separate the closed-loop system from the open-loop system.

[0108] This embodiment of the system includes a second compressor 122, a third compressor 123, a fourth compressor 124, a condenser 111, an evaporator 131, a combined condenser / evaporator and condenser heat exchanger 161, a combined condenser / evaporator and evaporator heat exchanger 171, a first subcooler 151, a second subcooler 152, a first expansion mechanism 141, a second expansion mechanism 142, and a third expansion mechanism 143. The evaporator 131 corresponds to the first heat exchange mechanism, the combined heat exchangers 171 and 161 correspond to intermediate heat exchange mechanisms, and the condenser 111 corresponds to the second heat exchange mechanism.

[0109] The refrigerant line R connects the evaporator 131, the fourth compressor 124, the condenser side of the composite heat exchanger 171, and the third expansion mechanism 143 to form the first circulation loop.

[0110] The refrigerant pipeline R connects the evaporator side of the composite heat exchanger 171, the third compressor 123, the condenser side of the composite heat exchanger 161, the second subcooler 152, and the second expansion mechanism 142 to form a second circulation loop.

[0111] The refrigerant pipeline R connects the evaporator side of the composite heat exchanger 171, the second compressor 122, the condenser 111, the first subcooler 151, and the first expansion mechanism 141 to form a third circulation loop. This third circulation loop includes a replenishment pipeline for refrigerant HWBI, a first discharge pipeline for discharging vapor ZQ1, a second discharge pipeline for discharging vapor ZQ2, and a gas-liquid separator FL. The replenishment pipeline is located on one side of the second subcooler 152 and connects to the evaporator-side inlet of the composite heat exchanger 161 after passing through the second subcooler 152. The gas-liquid separator FL is installed on the evaporator-side outlet pipeline of the composite heat exchanger 161, and is used to discharge liquid refrigerant. The first discharge pipeline connects to the outlet side of the second compressor 122, and the first compressor 121 is installed on the first discharge pipeline. The second discharge pipeline is located between the condenser 111 and the second compressor 122.

[0112] In the first cycle loop, the refrigerant is heated after passing through the evaporator 131, and after being compressed and pressurized by the fourth compressor 124, it enters the condenser of the composite heat exchanger 171 to release heat. The evaporator side of the composite heat exchanger 171 absorbs heat, and then the refrigerant returns to the evaporator 131 after expanding and depressurizing through the third expansion mechanism 143.

[0113] In the second circulation loop, the refrigerant is heated on the evaporator side of the composite heat exchanger 171, and after being compressed and pressurized by the third compressor 123, it enters the condenser of the composite heat exchanger 161 to release heat. The evaporator side of the composite heat exchanger 161 absorbs heat, and then the refrigerant returns to the evaporator side of the composite heat exchanger 171 after passing through the second subcooler 152 and the second expansion mechanism 142.

[0114] In the third circulation loop, high-temperature hot water enters through the replenishment pipeline, is heated by the second subcooler 152, and mixes with the water coming out of the first expansion mechanism 141 before entering the evaporation side of the composite heat exchanger 161 for heating. The evaporation side of the composite heat exchanger 161 outputs heated water and steam, which then pass through a gas-liquid separator. The hot water HW2 (80℃-100℃) is discharged, and the steam enters the second compressor 122 for compression and pressurization. It then splits into two paths: one path enters the first compressor 121 for further pressurization and discharge (ZQ1), and the other path is further split into two paths before entering the condenser. One path is discharged (ZQ2), and the other path enters the condenser 111 to release heat. After passing through the first subcooler 151 and the first expansion mechanism 141 in sequence, it enters the evaporation side of the composite heat exchanger 161.

[0115] On the heat source side, the waste hot water CW first enters the evaporation side of the composite heat exchanger 171, and together with the refrigerant on the condensation side of the composite heat exchanger 171, it provides heat to the refrigerant on the evaporation side. After being cooled, the waste hot water CW enters the evaporator 131 to provide heat for the evaporation of the refrigerant, and is discharged after being further cooled.

[0116] On the heat sink side, hot water is heated and discharged after passing through the first subcooler 151 and the condenser 111 in sequence. Example 20

[0117] refer to Figure 26 This embodiment is based on embodiment 19, with adjustments made to the third circulation loop. In the third circulation loop, condenser 111, condenser 112, and a fourth expansion mechanism 144 are installed. Condenser 111 is located on branch ZL, and the first discharge pipe for discharging steam ZQ1 is removed. This embodiment functions the same as embodiment 19, used to prepare steam and water at various temperatures. Condenser 112 can be used to heat water or air. Figure 26 In this circuit, evaporator 131 is equivalent to the first heat exchange mechanism, composite heat exchanger 171 and composite heat exchanger 161 are equivalent to intermediate heat exchange mechanisms, condenser 111 is equivalent to the intermediate branch heat exchange mechanism set on branch ZL, branch ZL is a branch pipe in the third circulation loop, and condenser 112 is equivalent to the second heat exchange mechanism.

[0118] In the first and second circulation loops, the refrigerant flow is the same as in Example 25. In the third circulation loop, high-temperature hot water enters through the replenishment pipeline, is heated by the second subcooler 152, and mixes with the water from the first expansion mechanism 141 before entering the evaporator side of the composite heat exchanger 161 for further heating. The evaporator side of the composite heat exchanger 161 outputs heated water and steam, which then pass through a gas-liquid separator. The hot water HW2 (80℃-100℃) is discharged, and the steam portion enters the second compressor 122 for compression and pressurization. It then splits into two paths: one path enters the first compressor 121 for further pressurization and then enters the condenser 112 to release heat; the other path is further split into two paths before entering the condenser 111. One path is discharged, namely ZQ2, and the other path enters the condenser 111 to release heat. Afterward, it merges with the refrigerant from the fourth expansion mechanism 144, passes through the first subcooler 151 and the first expansion mechanism 141 in sequence, and then enters the evaporator side of the composite heat exchanger 161.

[0119] Through the above embodiments 1 to 20, various variations of the refrigeration and heating cycle architecture of this application are demonstrated. From multi-stage compression and multi-stage expansion combined with interstage heat exchange through intermediate heat exchange mechanisms, to the addition of on / off valves and four-way valves, the application systematically demonstrates that the solution can seamlessly switch between refrigeration, heating, and combined cooling and heating modes under a single hardware architecture, achieving customized output of cooling and heating at various temperature levels to meet complex industrial and commercial needs. Simultaneously, it also illustrates that the solution of this application can improve the energy efficiency ratio and operational adaptability of the refrigeration and heating cycle system through flexible networked topology design, breaking the bottleneck of mismatch between constant evaporation / condensation temperature and variable temperature external medium in traditional single-stage cycles, and significantly reducing irreversible temperature difference losses during heat exchange.

[0120] The above embodiments are only used to explain the concept of the present invention, and are not intended to limit the protection of the present invention. Any non-substantial modifications made to the present invention using this concept should fall within the protection scope of the present invention.

Claims

1. A refrigeration and heating cycle system comprising an external medium, a first heat exchange mechanism and a second heat exchange mechanism for heat exchange between a refrigerant for internal circulation and the external medium, characterized by: Multiple compression mechanisms, multiple expansion mechanisms, several intermediate heat exchange mechanisms, and refrigerant pipelines are arranged between the first heat exchange mechanism and the second heat exchange mechanism; Both the first and second heat exchange mechanisms employ a heat release module, a heat absorption module, or a heat release / heat absorption switchable module; the intermediate heat exchange mechanism employs a heat release module, a heat absorption module, an internal / external heat exchange composite module, or a heat release / heat absorption switchable module. The refrigerant pipeline is used to connect several of the following mechanisms—the first heat exchange mechanism, the compression mechanism, the expansion mechanism, the intermediate heat exchange mechanism, and the second heat exchange mechanism—to form at least one circulating loop. In the same circulating loop, the compression mechanism compresses the refrigerant in the loop step by step, and the expansion mechanism expands the refrigerant in the loop step by step. The intermediate heat exchange mechanism is used to enable the refrigerant to exchange heat with the external medium. In two adjacent circulating loops, the refrigerants in the two loops exchange heat through the intermediate heat exchange mechanism and can simultaneously exchange heat with the external medium. Several external media flowing through the first heat exchange mechanism and / or the second heat exchange mechanism and / or the intermediate heat exchange mechanism are connected in series and / or in parallel and / or in a mixed series-parallel connection; Several circulation loops are provided with refrigerant discharge pipelines and refrigerant replenishment pipelines. The refrigerant discharge pipelines include a first steam discharge pipeline and a second steam discharge pipeline, which are respectively connected to the first compressor and the second compressor.

2. A refrigeration and heat cycle system as claimed in claim 1, wherein, When there is only one circulation loop, the first heat exchange mechanism adopts a heat absorption module, the second heat exchange mechanism adopts a heat release module, there are n compression mechanisms, there are n expansion mechanisms, and the intermediate heat exchange mechanism adopts either a heat absorption module or a heat release module. There are n-1 intermediate heat exchange mechanisms, wherein one end of the k-th intermediate heat exchange mechanism is connected to the refrigerant flow path between the k-th compression mechanism and the (k+1)-th compression mechanism, and the other end is connected to the refrigerant flow path between the k-th expansion mechanism and the (k+1)-th expansion mechanism; the n compression mechanisms compress the refrigerant step by step from the first heat exchange mechanism to the second heat exchange mechanism, and the corresponding n expansion mechanisms expand the refrigerant step by step from the second heat exchange mechanism to the first heat exchange mechanism; The n is an integer not less than 2, and the k is an integer where 1≤k≤n-1.

3. A refrigeration and heat cycle system as claimed in claim 2, wherein: The circulation loop is equipped with an on / off valve, which is used to selectively open or close the refrigerant flow path through the first heat exchange mechanism, the compression mechanism, the expansion mechanism, the intermediate heat exchange mechanism, or the second heat exchange mechanism.

4. A refrigeration and heat cycle system as claimed in claim 1, wherein: When there is only one circulation loop, the first heat exchange mechanism, the intermediate heat exchange mechanism, and the second heat exchange mechanism all adopt heat release / heat absorption switchable modules; there are n compression mechanisms, n expansion mechanisms, and n-1 intermediate heat exchange mechanisms, wherein one end of the kth intermediate heat exchange mechanism is connected to the refrigerant flow path between the kth and k+1th compression mechanisms, and the other end is connected to the refrigerant flow path between the kth and k+1th expansion mechanisms; one end of two adjacent heat release / heat absorption switchable modules is connected to the inlet and outlet of the compression mechanism at that end through a four-way valve; The n is an integer not less than 2, and the k is an integer where 1≤k≤n-1.

5. A refrigeration and heating cycle system as described in claim 1, characterized in that, When there is only one circulation loop, the first heat exchange mechanism adopts a heat release / heat absorption switchable module, the second heat exchange mechanism adopts a heat release module, and the intermediate heat exchange mechanism adopts a heat release / heat absorption switchable module; there are n compression mechanisms, n expansion mechanisms, and n-1 intermediate heat exchange mechanisms, wherein one end of the kth intermediate heat exchange mechanism is connected to the refrigerant flow path between the kth and k+1th compression mechanisms, and the other end is connected to the refrigerant flow path between the kth and k+1th expansion mechanisms; one end of two adjacent heat release / heat absorption switchable modules is connected to the inlet and outlet of the compression mechanism at that end through a four-way valve, and a one-way valve is provided on the outlet side of the compression mechanism connected to the four-way valve; the circulation loop is provided with several on / off valves, which are used to selectively open or close the refrigerant flow path through the first heat exchange mechanism, compression mechanism, expansion mechanism, intermediate heat exchange mechanism, or second heat exchange mechanism.

6. A refrigeration and heat cycle system as claimed in claim 1, wherein, When there is only one circulation loop, the first heat exchange mechanism adopts a heat absorption module, the second heat exchange mechanism adopts a heat release module, and the intermediate heat exchange mechanism adopts a heat release module. There are n compression mechanisms, n expansion mechanisms, and n-1 intermediate heat exchange mechanisms. The inlet of the kth intermediate heat exchange mechanism is connected to the outlet of the (k+1)th compression mechanism, the exhaust end is connected to the inlet of the kth compression mechanism through an exhaust pipe, and the liquid outlet end is connected to the refrigerant flow path between the kth expansion mechanism and the (k+1)th expansion mechanism. The n is an integer not less than 2, and the k is an integer where 1≤k≤n-1.

7. A refrigerant and heat cycle system as set forth in claim 1 wherein, When there are multiple circulation loops, branches are provided in several circulation loops. The branches are located between the first heat exchange mechanism and the intermediate heat exchange mechanism and / or between two adjacent intermediate heat exchange mechanisms and / or between the intermediate heat exchange mechanism and the second heat exchange mechanism. The branch is equipped with an intermediate branch heat exchange mechanism, which adopts one of the following: a heat release module, a heat absorption module, or a heat release / heat absorption switchable module. The external medium flows through the intermediate branch heat exchange mechanism.

8. A refrigeration and heat cycle system as claimed in any one of claims 1 to 7, wherein It includes a subcooler located on the inlet side and / or outlet side of the expansion mechanism, through which the external medium flows.

9. A refrigeration and heat cycle system as claimed in any one of claims 1 to 2, wherein The circulation loop is equipped with a gas-liquid separator, which is used to separate gaseous refrigerant and liquid refrigerant in the refrigerant. The liquid refrigerant enters the circulation loop in the original flow direction, while the gaseous refrigerant is diverted to the mechanism that needs to defrost and melt ice. The circulation loop is equipped with an on / off valve, which is used to selectively open or close the refrigerant flow path through the first heat exchange mechanism, the compression mechanism, the expansion mechanism, the intermediate heat exchange mechanism, the second heat exchange mechanism, or the gas-liquid separator.

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