A refrigerant composition and its application

Abstract

The present invention provides a refrigerant composition and its application. The refrigerant composition of the present invention comprises, based on the total mass of the refrigerant composition, 52wt%-62wt% of 1,1,1,2-tetrafluoroethane, 32wt%-40wt% of difluoromethane and 4wt%-8wt% of carbon dioxide, and the refrigerant composition is a non-azeotropic composition. The refrigerant composition of the present invention is suitable for low air volume (heat dissipation air volume less than 500m 3 / h) heat dissipation and high ambient temperature (above 35°C) scenarios.

Description

Technical Field

[0001] The present invention belongs to the technical field of refrigerants, and in particular relates to a refrigerant composition and application thereof. Background Art

[0002] Air conditioners with low heat dissipation airflow cannot quickly dissipate heat from the condenser, leading to heat accumulation. This insufficient airflow also reduces the heat exchange efficiency on the condenser surface, reducing the condenser's heat dissipation efficiency and increasing the condensation temperature. The condenser is unable to effectively condense the refrigerant from gas to liquid. In high-temperature environments, the ambient temperature is already high, making it difficult for the condenser to transfer heat to the surrounding air. This makes it more difficult for the condenser to dissipate heat, increasing the condensation temperature. High ambient temperatures necessitate even higher condensation temperatures to dissipate heat. Therefore, for air conditioners with low heat dissipation airflow or room air conditioners in high-temperature environments, a higher condensing temperature is often required to maintain cooling capacity. Given the limitations of airflow or ambient temperature, a higher condensing temperature becomes necessary to maintain refrigerant flow and system operation.

[0003] However, higher condensing temperatures increase the compressor's discharge temperature and pressure. System components (such as the compressor and condenser) must be appropriately designed to withstand these higher temperatures and pressures to prevent system overheating or damage. While ensuring system reliability, the choice of refrigerant is crucial: one that can operate stably under high temperatures and high pressures is crucial to ensure long-term reliable operation. From a refrigerant perspective, R22's superior thermodynamic properties and safety profile meet these requirements. However, it is ozone-depleting (ODP > 0), and according to the Montreal Protocol, R22 is facing global reductions or phase-out. Currently mainstream R410A and R32 suffer from excessively high system pressures and discharge temperatures in these scenarios. Consequently, equipment reliability considerations prevent them from achieving higher condensing temperatures, resulting in reduced cooling capacity. Furthermore, R32 is flammable and should not be used in certain applications, such as kitchens. While R134a can achieve higher condensing temperatures, its volumetric cooling capacity is relatively low, requiring a larger system size.

[0004] Therefore, refrigerant selection is a key factor in refrigeration system design and performance optimization. Finding a new mixed refrigerant that meets performance, environmental, and safety requirements has become a major challenge in the current field of refrigeration technology. It is necessary to develop a new refrigerant that, when used in the above scenarios, has performance (volume cooling capacity, cooling EER) close to or better than R22, while also having an ODP (Ozone Depletion Potential) of 0. Furthermore, the system must operate with a reasonable condensing pressure (<4 MPa) and exhaust temperature (<110°C). Summary of the Invention

[0005] The present invention aims to address at least one of the aforementioned technical problems in the prior art. To this end, the present invention provides a refrigerant composition suitable for low-volume heat dissipation or high ambient temperature scenarios. This refrigerant composition can replace R22, offers superior energy efficiency compared to R32, and has an ODP (Ozone Depletion Potential) of zero.

[0006] The present invention also provides a heat exchange system.

[0007] The present invention also provides a device for refrigeration.

[0008] The present invention also provides a device for heating.

[0009] A first aspect of the present invention provides a refrigerant composition comprising, based on the total mass of the refrigerant composition, 52 wt%-62 wt% of 1,1,1,2-tetrafluoroethane, 32 wt%-40 wt% of difluoromethane and 4 wt%-8 wt% of carbon dioxide, wherein the refrigerant composition is a non-azeotropic composition.

[0010] One of the technical solutions of the present invention regarding the refrigerant composition has at least the following beneficial effects:

[0011] The refrigerant composition of the present invention should have a safety level of A1 or A2L. The refrigerant composition is a non-azeotropic composition, which can boil or condense in a wide temperature range under constant pressure conditions, thereby generating temperature glide in the evaporator or condenser. Since the non-azeotropic mixed refrigerant has temperature glide during phase change, it can cooperate with the temperature gradient of the cooling medium to achieve better heat exchange. This feature, combined with a multi-row countercurrent heat exchanger, can reduce irreversible losses in the heat exchange process and improve system energy efficiency. The refrigerant composition of the present invention is suitable for small air volume (heat dissipation air volume less than 500m 3 / h) heat dissipation or high ambient temperature (above 35°C), specifically:

[0012] The safety level of the refrigerant composition is A1 or A2L, which means it is a low-toxic, non-flammable or low-flammable refrigerant with low safety risks to humans and the environment, and is suitable for various application scenarios.

[0013] The refrigerant composition is non-azeotropic, meaning its components can boil or condense independently under certain conditions, rather than forming a fixed boiling point. This property allows the refrigerant to experience temperature glide in the evaporator or condenser, helping to reduce irreversible losses during the heat exchange process.

[0014] The temperature glide characteristics of the refrigerant composition can be combined with multiple rows of counter-flow heat exchangers to help reduce irreversible losses in the heat exchange process. This means that the system loses less energy during the energy conversion process, thereby improving the energy efficiency of the system.

[0015] The refrigerant composition also has a relatively high condensing temperature, which is above 52°C, for example, above 65°C. When the condenser's heat dissipation air volume is small, due to the large temperature difference between the condenser and the ambient temperature, a small air volume can also achieve a good heat dissipation effect of the condenser, thereby increasing the cooling capacity. When used in a high-temperature environment, the condenser and the ambient temperature still maintain a certain temperature difference, which can achieve high-temperature cooling.

[0016] In the refrigerant composition of the present invention, since both R134a (i.e., 1,1,1,2-tetrafluoroethane) and R744 (i.e., CO2) are non-flammable, the flammability of the mixed refrigerant is lower than that of R32 (i.e., difluoromethane).

[0017] Taking all of these advantages into account, the refrigerant composition of the present invention can improve system energy efficiency when used in low-air-volume heat dissipation scenarios and high ambient temperatures. By reducing energy losses, the system can achieve more efficient cooling, reducing energy consumption and lowering operating costs. The refrigerant composition of the present invention also has the advantage of low toxicity or low flammability.

[0018] According to some embodiments of the present invention, the mass percentage of 1,1,1,2-tetrafluoroethane can be, for example, 52 wt%, 52.5 wt%, 53 wt%, 53.5 wt%, 54 wt%, 54.5 wt%, 55 wt%, 55.5 wt%, 56 wt%, 56.5 wt%, 57 wt%, 57.5 wt%, 58 wt%, 58.5 wt%, 59 wt%, 59.5 wt%, 60 wt%, 60.5 wt%, 61 wt%, 61.5 wt%, or 62 wt%, or a range value formed by any two of them.

[0019] According to some embodiments of the present invention, the mass percentage of difluoromethane can be, for example, 32wt%, 32.5wt%, 33wt%, 33.5wt%, 34wt%, 34.5wt%, 35wt%, 35.5wt%, 36wt%, 36.5wt%, 37wt%, 37.5wt%, 38wt%, 38.5wt%, 39wt%, 39.3wt%, or 40wt%, or a range value formed by any two of them.

[0020] According to some embodiments of the present invention, the mass percentage of carbon dioxide can be, for example, 2wt%, 2.5wt%, 3wt%, 3.5wt%, 4wt%, 4.5wt%, 5wt%, 5.5wt%, 6wt%, 6.5wt%, 7wt%, 7.5wt%, 8wt% or any value in the range formed by any two of them.

[0021] According to some embodiments of the present invention, the refrigerant composition comprises: 58 wt%-62 wt% of 1,1,1,2-tetrafluoroethane, 32 wt%-36 wt% of difluoromethane, and 4 wt%-7 wt% of carbon dioxide.

[0022] Selecting the above refrigerant composition can make the refrigerant safety level reach A1, further reduce the exhaust temperature and condensing pressure, and increase the relative volume cooling capacity and temperature glide, which is more suitable for scenarios with small air volume heat dissipation or high ambient temperature.

[0023] According to some embodiments of the present invention, under the operating conditions of an evaporating temperature of 13°C and a condensing temperature of 65°C, the exhaust temperature of the refrigerant composition is less than 107.5°C, the condensing pressure is less than 3.7 MPa, and the temperature glide at the condensing pressure is greater than 6.5°C.

[0024] The condensing temperature of the refrigerant composition is defined as the average value of the dew point temperature and the bubble point temperature at the corresponding pressure (condensing pressure); the evaporating temperature of the refrigerant composition is defined as the average value of the dew point temperature and the bubble point temperature at the corresponding pressure (evaporating pressure).

[0025] Lower exhaust gas temperature and condensing pressure generally mean that the system operates in a more stable state. This can reduce the system failure rate and reduce the need for maintenance and repair in the long run.

[0026] Furthermore, under given operating conditions, a higher temperature glide means the refrigerant better matches the air temperature during phase change heat transfer, which helps improve system energy efficiency. Under operating conditions with a condensing temperature of 65°C, the refrigerant composition has a temperature glide of 6.5 to 9.5°C. If the temperature glide is too low, the countercurrent heat transfer effect is not significant.

[0027] A second aspect of the present invention provides a heat exchange system comprising the refrigerant composition of the present invention, and:

[0028] a compressor for compressing the refrigerant composition;

[0029] a condenser connected to the compressor and configured to condense the compressed refrigerant composition;

[0030] a throttling element connected to the condenser and configured to reduce the pressure of the condensed refrigerant composition;

[0031] An evaporator is connected to the throttling element at one end and to the compressor at the other end, and is used for evaporating the low-pressure refrigerant composition.

[0032] One of the technical solutions of the present invention regarding the heat exchange system has at least the following beneficial effects:

[0033] Because the refrigerant composition has an A1 safety rating and is low-toxic and non-flammable, the heat exchange system has low safety risks during operation, making it suitable for a variety of application scenarios and ensuring system safety. Furthermore, the refrigerant composition is a non-azeotropic composition, capable of boiling or condensing over a wide temperature range under constant pressure conditions, thereby generating temperature glide and helping to improve the system's cooling efficiency. This means the heat exchange system can operate effectively over a wider temperature range and maintain a high cooling capacity even in high ambient temperatures.

[0034] In summary, the heat exchange system containing the refrigerant composition of the present invention can improve the refrigeration capacity and energy efficiency while ensuring the safety of the system, thereby providing users with a more reliable and efficient heat exchange solution.

[0035] According to some embodiments of the present invention, the heat exchange system further includes a first heat exchange device, which uses a first medium to cool the condenser. The condenser includes a plurality of rows of first heat exchange tubes arranged and sequentially connected along the flow direction of the first medium. The refrigerant composition enters the condenser from the first heat exchange tubes located downstream in the flow direction of the first medium and flows out of the condenser from the first heat exchange tubes located upstream in the flow direction of the first medium.

[0036] The temperature glide characteristics of the refrigerant composition, combined with the multi-row counterflow condenser, minimize irreversible losses during heat exchange, thereby improving the system's energy efficiency. By reducing energy losses, the system achieves more efficient cooling, reducing energy consumption and lowering operating costs. Combined with the multi-row counterflow condenser, heat dissipation is even more efficient. The counterflow design enhances the condenser's heat exchange efficiency, resulting in more effective heat dissipation.

[0037] Multi-row countercurrent condensers utilize energy more efficiently and reduce system energy consumption. This helps conserve energy and reduce carbon emissions, thereby lowering system operating costs and minimizing adverse environmental impacts. A heat exchange system with multi-row countercurrent condensers also improves system stability. Countercurrent condensers can better cope with fluctuating heat loads under varying operating conditions, maintaining stable system operation.

[0038] The first medium may include at least one of air and water. The first heat exchange device may include a fan for driving air flow or a pump for driving water flow.

[0039] According to some embodiments of the present invention, the number of the first heat exchange tubes is at least 2 rows, preferably at least 3 rows, and more preferably 4 to 10 rows.

[0040] The number of rows of the first heat exchange tubes can be at least two, for example, two, three, four, five, six, seven, eight, nine, or ten rows. A greater number of rows improves the condensation heat exchange effect, allowing for better utilization of the temperature glide characteristics of the refrigerant composition in conjunction with the temperature gradient of the heat dissipation medium for heat exchange. To avoid excessive flow resistance of the first medium, the number of rows of the first heat exchange tubes should not exceed ten.

[0041] According to some embodiments of the present invention, the first medium includes air, and the wind volume generated by the air flow is less than 500m 3 / h.

[0042] The first heat exchanger is a low-air-volume heat sink. Due to the high condensing temperature of the refrigerant combination, it exhibits temperature glide characteristics. Combined with a counterflow multi-row heat exchanger, it operates with low airflow, maintaining excellent heat dissipation even under these conditions. For low condenser airflow, the condenser should be configured with multiple rows, preferably no fewer than four, and the refrigerant and air arranged in counterflow to achieve optimal cascade heat exchange.

[0043] The cooling air volume is small (<500m 3 / h) air-conditioning products, including but not limited to room air conditioners and mobile air conditioners that use ducts to exhaust heat, or room air conditioners in high-temperature environments, such as T3 climate type (high temperature climate, maximum temperature 52°C) and higher temperatures as specified in GB / T7725.

[0044] According to some embodiments of the present invention, the first heat exchange device further comprises an exhaust pipe, the exhaust pipe is used to exhaust the air, and the diameter of the exhaust pipe is ≤120 mm. Preferably, the diameter of the exhaust pipe is ≥50 mm and ≤120 mm.

[0045] Understandably, due to limitations in the heat exchange system's installation space, location, or method, some scenarios require low airflow for the condenser. This typically results in a smaller ventilation cross-sectional area and a smaller exhaust duct cross-sectional area. Using a multi-row countercurrent condenser improves heat exchange efficiency while making more efficient use of limited space. This makes the system more flexible in installation and layout, making it suitable for locations with limited space or where a compact design is required. Considering both construction and airflow, the exhaust duct diameter should preferably be greater than or equal to 50 mm.

[0046] According to some embodiments of the present invention, the heat exchange system further includes a second heat exchange device, which utilizes a second medium to exchange heat with the evaporator. The evaporator includes a plurality of rows of second heat exchange tubes arranged and sequentially connected along the flow direction of the second medium. The refrigerant composition enters the evaporator from the second heat exchange tubes located downstream in the flow direction of the second medium and flows out of the evaporator from the second heat exchange tubes located upstream in the flow direction of the second medium.

[0047] Utilizing the temperature glide characteristics of the refrigerant composition during evaporation, combined with a multi-row countercurrent evaporator, reduces irreversible losses during the heat exchange process, thereby improving the system's energy efficiency. By reducing energy losses, the system can more effectively increase cooling capacity, reduce energy consumption, and lower operating costs. Combined with a multi-row countercurrent evaporator, heat exchange is even more efficient.

[0048] According to some embodiments of the present invention, the number of the second heat exchange tubes is at least 2 rows, preferably 2 to 10 rows.

[0049] The second medium may be at least one of air and water. The second heat exchange device may include a fan for driving air flow or a pump for driving water flow.

[0050] The number of rows of the second heat exchange tubes can be at least two, for example, two, three, four, five, six, seven, eight, nine, or ten rows. To avoid excessive flow resistance of the second medium, the number of rows of the second heat exchange tubes should not exceed ten. Typically, an evaporator is used to exchange heat with indoor air for cooling, and the air outlet area opposite the evaporator is relatively large. Therefore, the number of rows of the second heat exchange tubes can be smaller than the number of rows of the first heat exchange tubes.

[0051] According to some embodiments of the present invention, the condenser is designed to operate under the condition that the ambient temperature is higher than 35°C.

[0052] The refrigerant composition of the present invention and the countercurrent multi-row condenser can effectively operate in ambient temperatures above 35°C, ensuring that the system maintains high heat exchange efficiency even in high-temperature environments and avoiding poor heat exchange caused by excessively high ambient temperatures. Even in high-temperature environments, the refrigerant composition of the present invention maintains a temperature above the ambient temperature, enhancing system stability, ensuring long-term operation regardless of ambient temperature fluctuations, and reducing failure rates.

[0053] The condenser is designed to operate in ambient temperatures exceeding 35°C. This design is suitable for applications requiring high-temperature operation, such as industrial equipment cooling, server rooms, and kitchen equipment, meeting the heat dissipation requirements of various specialized environments. The condenser, operating at high ambient temperatures, efficiently exchanges heat, improving overall cooling efficiency and ensuring stable cooling even in high-temperature environments. Furthermore, the condenser's design can take high-temperature operating conditions into account, utilizing more heat-resistant and efficient materials and technologies to enhance system reliability and ensure stable operation in harsh environments. Despite operating in high-temperature environments, the condenser maintains efficient heat dissipation, thereby reducing compressor load, lowering system energy consumption, and achieving energy savings. A heat exchange system designed for high-temperature operation can adapt to a variety of installation and usage scenarios, operating effectively both indoors and outdoors. Therefore, a heat exchange system designed for operation in ambient temperatures exceeding 35°C can achieve multiple benefits, including efficient heat dissipation, improved stability, extended equipment life, wide applicability, improved cooling efficiency, enhanced reliability, significant energy savings, and flexible application.

[0054] According to some embodiments of the present invention, the heat exchange system is an integrated air conditioner, which includes a shell, and the compressor, the condenser, the throttling element and the evaporator are located in the shell and are interconnected by a refrigerant pipe.

[0055] An all-in-one air conditioner may include a main unit, which contains the core components of the air conditioner, including a compressor, condenser, evaporator, throttling element, a first heat exchange device, and a second heat exchange device. The main unit also includes a housing, in which the compressor, condenser, evaporator, and throttling element are located.

[0056] The evaporator is typically used for indoor heat exchange in a refrigeration system, absorbing indoor heat and evaporating the refrigerant within. The evaporator is connected to the compressor via a refrigerant pipe, allowing the refrigerant to circulate indoors.

[0057] The compressor is the core component of the refrigeration system, responsible for compressing the low-pressure refrigerant gas from the evaporator into high-pressure gas, increasing its temperature and pressure. The high-pressure gas discharged from the compressor enters the condenser through a pipeline, where the high-temperature and high-pressure gas is cooled into liquid refrigerant.

[0058] The compressor may be equipped with a gas-liquid separator, which is used to separate the refrigerant vapor and liquid refrigerant in the evaporator. The gaseous refrigerant in the gas-liquid separator enters the compressor through a pipeline, is sucked in by the compressor, and is compressed into high-pressure gas.

[0059] The condenser is used to dissipate heat, cooling the high-temperature, high-pressure refrigerant gas into liquid refrigerant. The liquid refrigerant in the condenser flows through a pipe into a throttling element, which reduces the refrigerant pressure.

[0060] A throttling element, such as an electronic expansion valve, is located between the condenser and evaporator. It controls the flow and pressure of the refrigerant, regulating the operating state of the refrigeration system. After passing through the throttling element, the refrigerant flows through a pipe into the evaporator, completing the refrigeration cycle.

[0061] The first heat exchange device for cooling the condenser may include an exhaust fan. The exhaust fan is used to discharge heat dissipated from the refrigeration system outdoors using flowing air, i.e., wind, to maintain the cooling effect of the refrigeration system. The exhaust fan can be located near the condenser and exhaust heat from the condenser outdoors by blowing or sucking air, thereby achieving heat dissipation from the refrigeration system.

[0062] The second heat exchange device, used for exchanging heat with the evaporator, may include a blower. This blower circulates indoor air and helps deliver heat to the cooling system during the cooling process. The blower is located near the evaporator and transfers the cooling energy from the evaporator to the indoor space by blowing or sucking air.

[0063] Through the cooperation and connection of these components, the refrigeration cycle process is realized and the cooling effect of the integrated air conditioner is achieved.

[0064] All-in-one air conditioners can also include:

[0065] The return air vent draws in indoor air from the room. It's connected to the unit's evaporator via a pipe or duct. The indoor air is drawn in through the return air vent and cooled by the evaporator.

[0066] An exhaust duct is used to discharge hot air or exhaust gas from the room to the outside. In some embodiments, the first heat exchange device may include an exhaust fan that exhausts the hot air after dissipation of heat by the condenser through the exhaust duct to the outside. The hot air from the condenser is driven by the exhaust fan and discharged through the exhaust duct to maintain a balanced temperature inside the main unit.

[0067] The air outlet is used to ventilate the cooled air after being processed by the evaporator into the room. In some embodiments, the cooled air is delivered by the supply blower and transported into the room through the air outlet. The air outlet area can be larger than the cross-sectional area of ​​the exhaust duct to ensure that the cooled air is effectively delivered to various areas of the room.

[0068] An air deflector can be located at the air outlet and can be moved, for example rotated, to control the direction and volume of air supplied. The air deflector allows the user to adjust the direction and volume of air supplied to achieve a comfortable air distribution.

[0069] According to some embodiments of the present invention, the workflow of the integrated air conditioner may be:

[0070] The return air vent draws in air from the room, which is then cooled by the evaporator in the main unit. The cooled air is then delivered to the room through the outlet. The direction and volume of the cool air can be adjusted using air guides. The condenser in the main unit then exhausts the hot air generated during the cooling process to the outside through an exhaust duct.

[0071] The integrated air conditioner is located indoors, and the condenser is connected to the outdoors through an exhaust pipe.

[0072] The exhaust duct can be connected to the outdoors by, for example, opening a hole in the wall. However, the small diameter of the hole in the wall limits the exhaust air volume and the diameter of the duct. The refrigerant composition used in the present invention has a relatively high condensing temperature, resulting in a large temperature difference with the primary medium used for air conditioning heat dissipation, such as air, resulting in excellent heat exchange efficiency, making it suitable for use in scenarios with low cooling air volumes. Furthermore, the present invention utilizes the temperature glide of the refrigerant composition, combined with a countercurrent multi-row heat exchanger, to improve heat exchange efficiency in these scenarios.

[0073] According to some embodiments of the present invention, the integrated air conditioner is at least partially located above the indoor ceiling.

[0074] The integrated air conditioner can be installed through a suspended ceiling, thus being installed in the upper portion of an indoor space. The integrated air conditioner is at least partially located above the indoor ceiling. A space exists between the ceiling and the top of the room, and the integrated air conditioner can be at least partially located within this space. Because this space is relatively enclosed, the ambient temperature surrounding the majority of the integrated air conditioner is higher than that of the indoor space below the ceiling. Therefore, a heat exchange system using the refrigerant composition of the present invention is more adaptable to applications in such higher ambient temperatures.

[0075] According to some embodiments of the present invention, the integrated air conditioner is a kitchen air conditioner, a bathroom air conditioner or a mobile air conditioner.

[0076] The integrated air conditioner using the refrigerant formula of the present invention is particularly suitable for scenarios where the exhaust duct area is limited or the ambient temperature around the condenser is high, such as kitchens, bathrooms, etc., as well as mobile air conditioners with exhaust ducts for indoor or outdoor use.

[0077] A third aspect of the present invention provides a device for refrigeration, comprising:

[0078] a main body, wherein the main body is configured as an object to be cooled;

[0079] a container comprising the refrigerant composition of the present invention;

[0080] The refrigerant composition is released from the container and evaporates near the body to cool the body.

[0081] A technical solution of the present invention regarding a device for refrigeration has at least the following beneficial effects:

[0082] The device for refrigeration adopts the refrigerant composition of the present invention, thereby having at least all the beneficial effects of the refrigerant composition of the present invention. Specifically, its non-azeotropic properties allow it to boil in a wide temperature range under constant pressure conditions, resulting in temperature glide, thereby improving the refrigeration efficiency in the evaporator. It can still maintain an excellent refrigeration effect at high ambient temperatures, ensuring that the main body is effectively cooled. The safety grade of the refrigerant composition is A1, which means that it is low in toxicity and non-flammable, reducing safety risks to the human body and the environment. The use of non-azeotropic compositions reduces energy loss and improves system energy efficiency, thereby reducing energy consumption and operating costs, meeting the requirements of energy conservation and environmental protection.

[0083] The device is suitable for small air volume heat dissipation (heat dissipation air volume less than 500m 3 / h) and high ambient temperature (above 35°C), it can be used in a variety of complex environments, such as electronic equipment cooling, industrial equipment heat dissipation, household air conditioning, etc., and has a wide range of applicability.

[0084] A fourth aspect of the present invention provides a device for heating, comprising:

[0085] a main body, wherein the main body is configured as an object to be heated;

[0086] a container comprising the refrigerant composition of the present invention;

[0087] The refrigerant composition is released from the container and condenses adjacent the body to heat the body.

[0088] The present invention relates to a technical solution for a device for heating, which has at least the following beneficial effects:

[0089] The device for heating adopts the refrigerant composition of the present invention, thereby having at least all the beneficial effects of the refrigerant composition of the present invention. Specifically, the non-azeotropic properties of the refrigerant composition of the present invention enable condensation within a wide temperature range under constant pressure conditions, resulting in temperature glide, thereby improving the heating efficiency in the condenser. It can maintain an excellent heating effect even at low ambient temperatures, ensuring that the main body is effectively heated. It can be used in a variety of complex environments, such as home heating, industrial equipment heating, heat pump systems, etc., and has a wide range of applicability. Since the heating system is efficient, energy-saving and has low maintenance costs, it can provide users with an economical and affordable heating solution, reducing long-term operation and maintenance costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0090] Figure 1 It is a temperature entropy diagram of the refrigerant composition and a schematic diagram of the wind temperature changes.

[0091] Figure 2 It is a schematic diagram of the air conditioning structure of the first embodiment of the heat exchange system of the present invention.

[0092] Figure 3 Schematic diagram of a refrigerant circulation system of a first embodiment of a heat exchange system of the present invention.

[0093] Figure 4 This is a flow diagram of a condenser according to the first embodiment of the heat exchange system of the present invention.

[0094] Figure 5 It is a schematic diagram of the air conditioning installation structure of the second embodiment of the heat exchange system of the present invention.

[0095] Figure 6 It is a schematic structural diagram of the air conditioner according to the second embodiment of the heat exchange system of the present invention, when viewed from a certain top view, with the casing removed.

[0096] Figure 7 It is a horizontal cross-sectional bottom view of the second embodiment of the heat exchange system of the present invention.

[0097] Figure 8 This is a flow diagram of a condenser according to the second embodiment of the heat exchange system of the present invention.

[0098] Reference numerals:

[0099] 100: host; 200: return air outlet; 300: exhaust duct; 400: supply air duct; 500: outlet;

[0100] 110: evaporator; 120: gas-liquid separator; 130: compressor; 140: condenser; 150: throttling element; 160: supply fan; 170: exhaust fan;

[0101] 1000: kitchen air conditioner; 1001: housing; 1002: first fan; 1003: first heat exchanger;

[0102] 1004: second fan; 1005: second heat exchanger; 1006: compression device; 1009: refrigerant pipe;

[0103] 1014: clearance groove; 1051: first pipeline; 1052: second pipeline;

[0104] 1101: first air inlet; 1103: second air inlet; 1104: second air outlet; 1110: first cavity; 1120: second cavity;

[0105] 2000: Ceiling; 2100: Keel; 2200: Spliced ​​decorative panels. DETAILED DESCRIPTION

[0106] The following are specific embodiments of the present invention, and the technical solutions of the present invention are further described in conjunction with the embodiments, but the present invention is not limited to these embodiments.

[0107] The following will clearly and completely describe the concept and technical effects of the present invention in conjunction with the embodiments to fully understand the purpose, features and effects of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, other embodiments obtained by those skilled in the art without creative work are all within the scope of protection of the present invention.

[0108] In the description of the present invention, reference to terms such as "one embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the exemplary expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0109] Unless otherwise specified, "room temperature" in the present invention means 25°C±5°C.

[0110] Unless otherwise specified, “about” in the present invention means that the allowable error is within ±1%.

[0111] If the specific conditions are not specified in the examples, the experiments were carried out under conventional conditions or those recommended by the manufacturer. All reagents or instruments used, if the manufacturer is not specified, are commercially available conventional products.

[0112] The relevant information of some refrigerants is shown in Table 1.

[0113] Table 1

[0114] Chemical formula Critical temperature / ℃ Critical pressure / MPa Security Level R134a <![CDATA[CH2FCF3]]> 101.1 4.06 A1 R32 <![CDATA[CH2F2]]> 78.11 5.78 A2L R744 <![CDATA[CO2]]> 30.98 7.38 A1 R22 <![CDATA[CHClF2]]> 96.14 4.99 A1

[0115] Examples 1 to 31

[0116] Examples 1 to 31 provide refrigerant compositions that are mixtures of R134a, R32, and R744. The mass percentages of R134a:R32:R744, based on the total mass of the refrigerant composition, are shown in Table 2.

[0117] Effect test

[0118] The mixed refrigerants of Examples 1 to 31, R22, and R32 were selected for theoretical cycle calculation.

[0119] The selected working conditions are: evaporating temperature 13°C, condensing temperature 65°C (for mixed refrigerants, evaporating temperature and condensing temperature are defined by the average value of dew point and bubble point under a certain pressure), superheat 2°C, subcooling 10°C, and compressor isentropic efficiency 0.7.

[0120] Refrigerant properties were obtained using REFPROP software. Comparisons were made of volumetric cooling capacity, energy efficiency (EER), condensing pressure, pressure ratio, temperature glide (at condensing pressure), and exhaust temperature. The relative values ​​in the calculations were based on R22.

[0121] The results are shown in Table 2.

[0122] Table 2

[0123]

[0124]

[0125] From the results in Table 2, it can be seen that although R32 has a significantly higher relative volumetric cooling capacity than R22, the condensing pressure and exhaust temperature are very high when the system is running, which is not conducive to equipment reliability, and the energy efficiency is reduced by about 7%.

[0126] For the refrigerant compositions of the present invention, the relative volumetric cooling capacity of all examples exceeded that of R22, exceeding 115% of that of R22. The relative energy efficiency was only slightly lower than that of R22, but the difference was within 4%. The condensing pressure was lower than that of R32 and slightly higher than that of R22, with a pressure ratio essentially the same as that of R22.

[0127] By comparing different embodiments, we can find that:

[0128] According to the test results of Examples 1, 6, 10, and 16, by keeping the R32 ratio unchanged and increasing the CO2 ratio (correspondingly reducing the R134a ratio), the refrigerant composition shows a trend of increasing relative volumetric cooling capacity, decreasing relative pressure ratio, and increasing temperature glide.

[0129] According to the test results of Examples 10, 15, 21, 25, and 29, by keeping the CO2 ratio unchanged and increasing the R32 ratio (correspondingly reducing the R134a ratio), the refrigerant composition shows a trend of increasing volumetric refrigeration capacity and slightly decreasing relative pressure ratio. Compared with the case where CO2 replaces R134a, the changes in various indicators are smaller.

[0130] According to the test results of Examples 7 to 10, by keeping the R134a ratio unchanged and increasing the R32 ratio (correspondingly reducing the CO2 ratio), the refrigerant composition shows a trend of decreasing condensing pressure and exhaust gas temperature.

[0131] The above test results show that changes in the amounts of different components in the refrigerant composition of the present invention will have different degrees of impact on the relative volumetric cooling capacity, relative refrigeration energy efficiency, condensing pressure, relative pressure ratio, temperature glide, exhaust temperature, etc. of the heat exchange system.

[0132] To replace R22 without increasing the system pressure and exhaust temperature as much as R32, the refrigerant composition may be composed of 52 wt%-62 wt% of 1,1,1,2-tetrafluoroethane, 32 wt%-40 wt% of difluoromethane, and 4 wt%-8 wt% of carbon dioxide.

[0133] In order to stably maintain the safety level of the refrigerant composition to A1 under the operating conditions of an evaporating temperature of 13°C and a condensing temperature of 65°C, the exhaust temperature is less than 105°C, the condensing pressure is less than 3.6 MPa, the relative volumetric cooling capacity is above 115%, and the temperature glide is greater than 7°C, so as to better meet the system reliability requirements and the heat exchange requirements of small exhaust volume and high temperature working environment, the refrigerant composition can be composed of 58wt%-62wt% of 1,1,1,2-tetrafluoroethane, 32wt%-36wt% of difluoromethane and 4wt%-7wt% of carbon dioxide.

[0134] And from the above test results, it can be seen that the refrigerant composition of the embodiment of the present invention has obvious temperature glide phenomenon, and can be used in conjunction with a countercurrent multi-row heat exchanger to achieve better heat exchange effect. Figure 1 As shown in the temperature-entropy diagram and the wind temperature change, during the condensation process, the temperature change of the refrigerant is not a parallel line. The condensation temperature of the refrigerant gradually decreases during the condensation process, and the wind passing through the condenser usually gradually heats up along the direction of air flow. When the refrigerant composition of the present invention is combined with a countercurrent multi-row condenser, a large temperature difference between the refrigerant temperature and the air temperature can be maintained both upstream and downstream in the air flow direction, thereby achieving a better heat exchange effect.

[0135] In some examples, the condenser can be cooled by water in addition to air cooling. For example, the condensed water on the surface of the evaporator is gathered under the condenser, and then the water is sprayed onto the heat exchange tubes of the condenser and the exhaust air flowing through the condenser through a water wheel or a water distributor, thereby reducing the air temperature. Figure 1 As shown in the figure, the air temperature will fluctuate. But in general, the air temperature will rise along the direction of air flow through the condenser.

[0136] The refrigerant composition of the present invention is suitable for scenarios with unfavorable heat dissipation conditions, has an ODP of 0, a volumetric cooling capacity superior to R22, and comparable energy efficiency.

[0137] In addition, using R1234ze(E), R152a or R1270 to replace the R134a component can also reduce the GWP value of the refrigerant composition, but will increase the flammability of the mixed refrigerant. Therefore, the present invention does not use R1234ze(E), R152a or R1270.

[0138] Heat exchange system first embodiment

[0139] This embodiment provides a heat exchange system, which is an integrated air conditioner.

[0140] The integrated air conditioner is embedded in the space between the indoor ceiling and the roof. The hot air is discharged to the outside through the exhaust duct through the exhaust holes on the wall. Due to the small diameter of the exhaust holes and the exhaust duct (no more than 120mm), the exhaust air volume is small (<500m 3 / h), when the air conditioner is placed in the kitchen, the ambient temperature inside the ceiling may be high (higher than 35°C). Therefore, in order to ensure a certain cooling output, it is necessary to use the refrigerant composition of the present invention.

[0141] like Figures 2 to 4 As shown, the integrated air conditioner is provided with a main unit 100, a return air port 200 is provided near the main unit 100, and the main unit 100 is connected to an exhaust duct 300 and an air supply duct 400, and the diameter of the exhaust duct 300 is ≤120 mm.

[0142] The main unit 100 includes core components of the air conditioner, including a compressor 130 , a condenser 140 , an evaporator 110 , an expansion valve 150 , an exhaust fan 170 , and a supply fan 160 .

[0143] The return air vent 200 is used to draw in indoor air from below the ceiling. The return air vent 200 can be connected to the evaporator 110 via a pipe or air duct, or it can be located near the air inlet side of the evaporator 110. Indoor air is drawn in through the return air vent 200 and cooled by the evaporator 110.

[0144] The exhaust duct 300 is used to discharge hot air or exhaust gas from the room to the outside. In some embodiments, the exhaust fan 170 discharges the hot air after the heat is dissipated by the condenser 140 to the outside through the exhaust duct 300. The hot air from the condenser 140 is driven by the exhaust fan 170 and discharged through the exhaust duct 300. In some examples, part of the air that flows into the ceiling through the return air vent 200 is used to dissipate heat from the condenser 140 and is then discharged to the outside through the exhaust duct 300.

[0145] The air supply duct 400 is used to pass the processed cold air into the room. In some embodiments, the air cooled by the evaporator 110 is driven by the air supply fan 160 and transported into the room through the air supply duct 400. The air supply duct 400 is connected to the air outlet 500, and the air outlet 500 faces the room. An air guide plate may be provided at the air outlet 500, and the air guide plate can be moved, for example rotated, to control the direction and amount of air supply. In some embodiments, the end of the air supply duct 400 is connected to the air outlet 500, and the air outlet 500 is set on the wall or ceiling in the room. The air guide plate allows the user to adjust the direction and amount of air supply to achieve comfortable air distribution.

[0146] In some examples, the workflow of the integrated air conditioner may be:

[0147] Air is drawn in from the room through the return air vent 200. This air is cooled by the evaporator 110 in the main unit 100 and then delivered to the room through the air supply duct 400. Cooled air then enters the room through the air outlet 500. The condenser 140 in the main unit 100 exhausts the hot air generated during the cooling process to the outside through the exhaust duct 300.

[0148] In some examples, the integrated air conditioner performs condensation heat dissipation in high ambient temperatures. The integrated air conditioner can be specifically a kitchen refrigeration system, and the refrigeration system is composed of an evaporator 110, a gas-liquid separator 120, a compressor 130, a condenser 140, and an expansion valve 150. The expansion valve 150 serves as a throttling element. In particular, in order to better achieve countercurrent heat dissipation, the condenser 140 needs to be arranged in multiple rows (for example, not less than 4 rows), and the refrigerant and the air are arranged in a countercurrent form to form a stepped heat exchange. At this time, the temperature glide during the condensation of the mixed refrigerant can better match the refrigerant and air temperatures, reduce irreversible losses in the heat exchange process, and improve the energy efficiency of the system. The outer diameter of the condenser copper tube can be selected from 5-7mm, specifically 7mm.

[0149] The condenser can operate at an ambient temperature above 35°C.

[0150] In some examples, the integrated air conditioner is a kitchen refrigeration system, which includes an evaporator 110, a gas-liquid separator 120, a compressor 130, a condenser 140, and an expansion valve 150 interconnected by a refrigerant pipe.

[0151] In kitchen refrigeration systems:

[0152] The evaporator 110 is the refrigeration part of the refrigeration system, which is used to absorb indoor heat and use it to evaporate the refrigerant. The evaporator 110 is connected to the gas-liquid separator 120 through a refrigerant pipeline.

[0153] The gas-liquid separator 120 is used to separate the refrigerant vapor and liquid refrigerant in the evaporator 110. The gaseous refrigerant in the gas-liquid separator 120 enters the compressor 130 through a pipeline, is sucked in by the compressor and compressed into high-pressure gas, and the liquid refrigerant can enter the condenser 140 or the expansion valve 150 or return to the evaporator 110.

[0154] Compressor 130 is the core component of the refrigeration system, responsible for compressing low-pressure refrigerant gas into high-pressure gas, increasing its temperature and pressure. The high-pressure gas discharged from compressor 130 enters condenser 140 through a pipeline. In condenser 140, the high-temperature, high-pressure gas is cooled and converted into liquid refrigerant.

[0155] Condenser 140 is used to cool the high-temperature, high-pressure refrigerant gas into liquid refrigerant by dissipating heat. The liquid refrigerant in condenser 140 enters expansion valve 150 through a pipeline. Expansion valve 150 can be, for example, an electronic expansion valve that controls the flow rate and regulates the pressure of the refrigerant.

[0156] It should be noted that the reference Figure 4 As shown, the condenser can be designed into multiple rows, and water wheels can be set between adjacent rows of heat exchangers to spray water. The evaporation of water droplets can cool the air that has been heat exchanged by the previous group of condensers, increase the heat transfer temperature difference of the next group of condensers, thereby further enhancing the heat dissipation capacity of the condenser and thus improving the cooling capacity of the system.

[0157] Figure 4 The diagram illustrates a four-row condenser and refrigerant flow arrangement. The four rows are divided into two groups (2+2), with a water impeller positioned between the two groups to atomize the condensed water. The refrigerant in condenser 140 can be designed to include multiple parallel branches, each of which flows countercurrently to the air flow.

[0158] Expansion valve 150 is located between condenser 140 and evaporator 110 and is used to reduce the pressure of the refrigerant. Expansion valve 150 can be, for example, an electronic expansion valve and can be used to regulate the operating state of the refrigeration system. After being throttled by expansion valve 150, the refrigerant enters evaporator 110 through a pipeline, completing the refrigeration cycle.

[0159] Second embodiment of heat exchange system

[0160] like Figures 5 to 8 As shown, this embodiment provides a kitchen air conditioner 1000 using the refrigerant composition of the present invention. The kitchen air conditioner 1000 can be suspended and installed on a ceiling 2000 , which includes a keel 2100 as a supporting structure and a spliced ​​decorative panel 2200 installed on the keel 2100 .

[0161] The kitchen air conditioner 1000 includes a housing 1001, a first fan 1002, a second fan 1004, a first heat exchanger 1003, a second heat exchanger 1005, a compression device 1006, an electrical control box 2a, and a throttling element. The first fan 1002, the second fan 1004, the first heat exchanger 1003, the second heat exchanger 1005, the compression device 1006, and the throttling element are located within the housing 1001, forming an integrated or monolithic structure. The first fan 1002 can be used to supply air to the room, while the second fan 1004 can be used to exhaust air to the outside. The first heat exchanger 1003 functions as an evaporator during cooling, while the second heat exchanger 1005 functions as a condenser during cooling. The compression device 1006 can be a compressor.

[0162] The top of the housing 1001 is recessed downward to form a clearance groove 1014. The clearance groove 1014 can be configured as a straight strip. The clearance groove 1014 extends from one side of the housing 1001 to the other side, horizontally penetrating the housing 1001. The depth of the clearance groove 1014 can be 80% to 95% of the vertical dimension of the housing 1001. The clearance slot 1014 allows the keel 2100 to pass through. To install the kitchen air conditioner 1000, simply align the opening of the clearance slot 1014 with the keel 2100 below the ceiling 2000. Then, raise the kitchen air conditioner 1000 so that the keel 2100 enters the clearance slot 1014 until it rests at the bottom of the clearance slot 1014. Finally, secure the kitchen air conditioner 1000, for example, by attaching it to a ceiling, and installation is complete. The installed keel does not need to be removed during installation. The kitchen air conditioner 1000 is at least partially located above the ceiling 2000. The chassis of the kitchen air conditioner 1000 can be located below the ceiling 2000 and covered by a panel. After the kitchen air conditioner 1000 has been operating in cooling mode for a period of time, the temperature above the ceiling 2000 is higher than the indoor temperature below, reaching over 35°C.

[0163] A first cavity 1110 and a second cavity 1120 are provided within the housing 1001. The first cavity 1110 and the second cavity 1120 are separated by a clearance slot 1014. The housing 1001 is provided with a first air inlet 1101, a first air outlet (not shown), a second air inlet 1103, and a second air outlet 1104. The first air inlet 1101 is provided on a sidewall of the first cavity 1110. The first air inlet 1101 is connected to the indoor space, for example, via a return air vent spaced apart from the housing 1001, and is used to deliver air into the first cavity 1110. The first air outlet is provided on the bottom wall of the first cavity 1110. The first air outlet is used to output air inputted into the first cavity 1110 from the first air inlet 1101 out of the first cavity 1110. The second air inlet 1103 is provided on a sidewall of the second cavity 1120. The second air inlet 1103 is connected to the indoor space, for example, through a return air vent, and is used to deliver air into the second cavity 1120. The second air outlet 1104 is disposed on a sidewall of the second cavity 1120. The second air outlet 1104 is used to discharge air inputted from the second air inlet 1103 into the second cavity 1120. The second air outlet 1104 can be connected to the outdoors. For example, the second air outlet 1104 can discharge the air from the second cavity 1120 outdoors through an exhaust pipe that passes through an exhaust hole disposed in the wall. The diameter of the exhaust pipe is ≤120 mm.

[0164] The first fan 1002 is connected to the housing 1001. The first fan 1002 is disposed in the first cavity 1110. The first fan 1002 is configured to drive the air in the first cavity 1110 to flow from the first air inlet 1101 of the first cavity 1110 to the first air outlet of the first cavity 1110, thereby circulating the air between the indoor space and the first cavity 1110.

[0165] The first heat exchanger 1003 is disposed in the first cavity 1110. The air in the first cavity 1110 flows through the first heat exchanger 1003 when flowing from the first air inlet 1101 to the first air outlet, and the first heat exchanger 1003 can exchange heat with the air.

[0166] The second fan 1004 may be disposed in the second cavity 1120. The second fan 1004 is configured to drive the air in the second cavity 1120 to flow from the second air inlet 1103 of the second cavity 1120 to the second air outlet 1104 of the second cavity 1120, so as to draw the air from the indoor space into the second cavity 1120 and then transport the air from the second cavity 1120 to the outdoor space.

[0167] The second heat exchanger 1005 is disposed in the second cavity 1120. The second heat exchanger 1005 can be disposed near the second air inlet 1103. The air in the second cavity 1120 flows through the second heat exchanger 1005 when flowing from the second air inlet 1103 to the second air outlet 1104, and the second heat exchanger 1005 can exchange heat with the air.

[0168] The compression device 1006 can be disposed within the housing 1001. The compression device 1006 can be disposed within the first cavity 1110 or the second cavity 1120. In this embodiment, the compression device 1006 is disposed within the second cavity 1120. The compression device 1006, the second heat exchanger 1005, the throttling element, and the first heat exchanger 1003 are sequentially connected via a refrigerant pipe 1009 to form a refrigeration circuit. The refrigeration circuit can be pre-filled with the refrigerant composition of the present invention. The compression device 1006 drives the refrigerant to circulate between the first heat exchanger 1003 and the second heat exchanger 1005. A throttling element is also disposed between the first heat exchanger 1003 and the second heat exchanger 1005. In the cooling mode of the kitchen air conditioner 1000, the refrigerant evaporates when flowing through the first heat exchanger 1003, absorbing heat from the air flowing through the first cavity 1110. The refrigerant condenses when flowing through the second heat exchanger 1005, releasing heat to the air flowing through the second cavity. In this way, the temperature of the air flowing through the first cavity decreases, and the air transported from the first air outlet of the first cavity to the indoor air is cold air. Correspondingly, the temperature of the air flowing through the second cavity increases, and the air transported from the second cavity to the outdoor air is hot air.

[0169] Among them, the second heat exchanger 1005 can be a straight heat exchanger with a compact structure. The second heat exchanger 1005 includes multiple rows of first heat exchange tubes, and the number of rows of first heat exchange tubes is at least 4 rows, for example, 6 rows. The multiple rows of first heat exchange tubes are arranged in sequence along the air flow direction within the second cavity 1120 and are connected in series. For example, the ends of adjacent rows of first heat exchange tubes are connected by U-shaped tubes. The refrigerant composition of the present invention enters the second heat exchanger 1005 from the first heat exchange tube located downstream in the air flow direction and leaves the second heat exchanger 1005 from the first heat exchange tube located upstream in the air flow direction, realizing countercurrent heat exchange on the condenser side.

[0170] The first heat exchanger 1003 is constructed as a U-shaped heat exchanger, which has a large contact area with the air and a high heat exchange efficiency. The first fan 1002 is arranged in the internal cavity enclosed by the first heat exchanger 1003, and the U-shaped heat exchanger can be arranged around the first fan 1002, with a compact layout. The first heat exchanger 1003 includes at least 2 rows of U-shaped second heat exchange tubes, and at least 2 rows of second heat exchange tubes are arranged in sequence and in series along the air flow direction of the first chamber 1100. For example, the ends of the second heat exchange tubes in adjacent rows are connected by U-shaped tubes. The number of rows of second heat exchange tubes can be 2 rows, for example. The refrigerant composition of the present invention enters the first heat exchanger 1003 from the second heat exchange tube located downstream in the air flow direction, and leaves the first heat exchanger 1003 from the second heat exchange tube located upstream in the air flow direction, realizing countercurrent heat exchange on the evaporator side.

[0171] In this embodiment, the electrical control box 2a includes a control board 27a and a cooling pipe 24a. The cooling pipe 24a is used to dissipate heat from the control board 27a. The cooling pipe 24a draws refrigerant from the second heat exchanger 1005, and the refrigerant flows through the cooling pipe 24a and then returns to the second heat exchanger 1005. The cooling pipe 24a can draw refrigerant from the main flow path or the branch flow path of the second heat exchanger 1005. After passing through the cooling pipe 24a, the refrigerant flows back to the second heat exchanger 1005 before the subcooling section of the second heat exchanger 1005, and then flows to the subcooling section.

[0172] When the kitchen air conditioner 1000 is working, the control panel 27a will generate heat and transfer the heat to the cooling pipe 24a. When the kitchen air conditioner 1000 is in cooling mode, the compression device 1006 compresses the refrigerant and then outputs the high-temperature and high-pressure refrigerant to the second heat exchanger 1005. When the refrigerant flows through the second heat exchanger 1005, the heat is transferred to the air flowing through the second cavity, and the refrigerant is cooled to a low-temperature refrigerant. The refrigerant is transported from the second heat exchanger 1005 to the cooling pipe 24a. When the refrigerant flows through the cooling pipe 24a, it absorbs the heat of the control panel 27a, thereby bringing the heat emitted by the control panel 27a out of the electrical control box 2a. The refrigerant then re-enters the second heat exchanger 1005 for countercurrent heat exchange with the air, so that the cooling effect is not attenuated.

[0173] The second heat exchanger 1005 may be provided with multiple parallel pipelines, each of which exchanges heat in a countercurrent direction to the air flow. Due to objective factors (e.g., varying heat exchange efficiencies between heat exchange tubes at different locations and a heat dissipation medium such as air), it may be difficult for multiple pipelines to achieve uniform heat exchange performance. This results in different refrigerant temperatures being output from the multiple pipelines, with pipelines with better heat exchange performance outputting lower refrigerant temperatures and pipelines with poorer heat exchange performance outputting higher refrigerant temperatures. Large temperature differences in the refrigerant output from the multiple heat exchange flow paths can also lead to reduced condensing efficiency of the condenser, a decrease in cooling capacity, and increased compressor power.

[0174] In some examples, second heat exchanger 1005 includes a first pipeline 1051 and a second pipeline 1052 connected in parallel. Because first pipeline 1051 has greater contact with the cooling water sprayed by the water wheel, the heat exchange efficiency of first pipeline 1051 is higher than that of second pipeline 1052. Connecting cooling pipe 24a in series with first pipeline 1051, i.e., introducing refrigerant from first pipeline 1051 into cooling pipe 24a for electronically controlled heat dissipation before returning to first pipeline 1051 or second heat exchanger 1005, brings the temperatures of the refrigerants output from the two pipelines closer together, reducing the temperature difference between the refrigerants at the time of confluence. This can improve the condensing efficiency of second heat exchanger 1005, the cooling capacity of the air conditioner, and reduce the power of the compressor. After the refrigerant returns to the second heat exchanger 1005 through the cooling pipe 24a, the refrigerant composition therein continues to dissipate heat in a countercurrent manner with the air, or after the refrigerant returns to the second heat exchanger 1005 through the cooling pipe 24a, it merges with the second pipeline 1052 and continues to dissipate heat in a countercurrent manner with the air, resulting in a good heat dissipation effect.

[0175] In other embodiments of the present invention, the refrigerant composition of the present invention is also suitable for heat pump hot water scenarios. In this case, the condenser adopts water cooling (shell heat exchanger, plate heat exchanger, etc.), and the water and refrigerant are arranged in countercurrent, which can achieve a higher water outlet temperature.

[0176] The present invention has been described in detail above with reference to the embodiments. However, the present invention is not limited to the above embodiments. Various changes can be made within the scope of knowledge possessed by ordinary technicians in the relevant technical field without departing from the spirit of the present invention.

Claims

1. A refrigerant composition, characterized in that Based on the total mass of the refrigerant composition, the refrigerant composition consists of the following components: 58 wt%-62 wt% of 1,1,1,2-tetrafluoroethane, 32 wt%-36 wt% of difluoromethane and 4 wt%-7 wt% of carbon dioxide. The refrigerant composition is a non-azeotropic composition.

2. The refrigerant composition according to claim 1, wherein Under the operating conditions of an evaporating temperature of 13°C and a condensing temperature of 65°C, the exhaust temperature of the refrigerant composition is less than 105°C, the condensing pressure is less than 3.6 MPa, and the temperature glide at the condensing pressure is greater than 7°C.

3. A heat exchange system, characterized in that: A refrigerant composition comprising the refrigerant composition according to any one of claims 1 or 2, and: a compressor for compressing the refrigerant composition; a condenser connected to the compressor and configured to condense the compressed refrigerant composition; a throttling element connected to the condenser and configured to reduce the pressure of the condensed refrigerant composition; The evaporator has one end connected to the throttling element and the other end connected to the compressor, and is used for evaporating the low-pressure refrigerant composition.

4. The heat exchange system according to claim 3, characterized in that: The heat exchange system also includes a first heat exchange device, which uses a first medium to cool the condenser. The condenser includes multiple rows of first heat exchange tubes arranged along the flow direction of the first medium and connected in sequence. The refrigerant composition enters the condenser from the first heat exchange tubes located downstream in the flow direction of the first medium and flows out of the condenser from the first heat exchange tubes located upstream in the flow direction of the first medium.

5. The heat exchange system according to claim 4, characterized in that: The first heat exchange tubes are in at least three rows.

6. The heat exchange system according to claim 4, characterized in that: The first heat exchange tubes are arranged in 4 to 10 rows.

7. The heat exchange system according to claim 4, characterized in that: The first medium includes air, and the air volume generated by the air flow is less than 500m 3 / h.

8. The heat exchange system according to claim 7, characterized in that: The first heat exchange device further includes an exhaust pipe, which is used to exhaust the air, and the diameter of the exhaust pipe is ≤120 mm.

9. The heat exchange system according to claim 7, characterized in that: The diameter of the exhaust pipe is ≥50mm and ≤120mm.

10. The heat exchange system according to claim 3, characterized in that: The heat exchange system also includes a second heat exchange device, which uses a second medium to exchange heat with the evaporator. The evaporator includes multiple rows of second heat exchange tubes arranged and connected in sequence along the flow direction of the second medium. The refrigerant composition enters the evaporator from the second heat exchange tubes located downstream in the flow direction of the second medium and flows out of the evaporator from the second heat exchange tubes located upstream in the flow direction of the second medium.

11. The heat exchange system according to claim 10, characterized in that: The number of the second heat exchange tubes is 2 to 10.

12. The heat exchange system according to claim 4, characterized in that: The condenser is suitable for working under the condition that the ambient temperature is higher than 35°C.

13. The heat exchange system according to any one of claims 3 to 12, characterized in that: The heat exchange system is an integrated air conditioner, which includes a shell. The compressor, the condenser, the throttling element and the evaporator are located in the shell and are interconnected by a refrigerant pipe.

14. The heat exchange system according to claim 13, characterized in that: The integrated air conditioner is located indoors, and the condenser is connected to the outdoors through an exhaust pipe.

15. The heat exchange system according to claim 13, characterized in that: The integrated air conditioner is installed in a suspended ceiling manner, and at least a portion of the integrated air conditioner is located above the indoor ceiling.

16. The heat exchange system according to claim 13, characterized in that: The integrated air conditioner is a kitchen air conditioner, a bathroom air conditioner or a mobile air conditioner.

17. A device for refrigeration, characterized in that: include: a main body, wherein the main body is configured as an object to be cooled; A container comprising the refrigerant composition according to any one of claims 1 or 2; The refrigerant composition is released from the container and evaporates near the body to cool the body.

18. A device for heating, characterized in that: include: a main body, wherein the main body is configured as an object to be heated; A container comprising the refrigerant composition according to any one of claims 1 or 2; The refrigerant composition is released from the container and condenses adjacent the body to heat the body.

Images