Efficient gradient refrigeration cycle system and operation method thereof

Abstract

The invention provides an efficient gradient refrigeration cycle system and an operation method thereof. The efficient gradient refrigeration cycle system comprises a heat release unit, a pressure reduction unit and a gradient refrigeration module. And a temperature gradient control mechanism is arranged in the gradient refrigeration module, and the temperature gradient control mechanism is configured to enable the temperature of a refrigeration working medium to be gradually increased according to a preset curve in the heat absorption process to be matched with the temperature curve of a cooled medium so as to reduce heat transfer # imgabs0 # loss. Dynamic matching of temperature curves of a refrigerating working medium and a cooled medium is achieved through the temperature gradient control mechanism, and irreversible loss in the heat transfer process is greatly reduced; a multi-stage pressure regulation and control structure or a variable-volume closed structure is adopted, and a high-precision sensor array and an intelligent control system are matched, so that the temperature of a refrigeration working medium can be accurately increased according to a preset curve, the controllability and stability of the refrigeration process are greatly improved, and the high-precision temperature control requirement is met.

Description

Technical Field

[0001] The present invention belongs to the field of refrigeration technology, and in particular relates to a high-efficiency gradient refrigeration cycle system and an operation method thereof. Background Art

[0002] In the cooling process of traditional refrigeration systems, due to the large temperature difference between the refrigerant and the cooled medium, a large number of irreversible In the prior art, a single-stage refrigeration cycle is usually used. The refrigerant absorbs heat at a constant temperature in the evaporator, which does not match the temperature curve of the cooled medium, resulting in a large heat transfer temperature difference and increasing system energy consumption. Therefore, how to reduce the heat transfer process? Reducing losses and improving system energy efficiency have become technical issues that need to be urgently solved in this field. Summary of the invention

[0003] In order to overcome the shortcomings of the prior art, the purpose of the present invention is to provide a high-efficiency gradient refrigeration cycle system and its operation method to solve the problems in the existing refrigeration heat transfer process. Large losses and low energy efficiency.

[0004] To solve the above problems, the technical solution adopted by the present invention is as follows:

[0005] In a first aspect, the present invention provides a high-efficiency gradient refrigeration cycle system, comprising a heat release unit, a pressure reduction unit and a gradient refrigeration module;

[0006] The gradient refrigeration module is provided with a temperature gradient control mechanism, which is configured to gradually increase the temperature of the refrigerant according to a preset curve during the heat absorption process, matching the temperature curve of the cooled medium to reduce heat transfer. damage.

[0007] In some embodiments, the cooled medium forms a countercurrent heat exchange relationship with the refrigerant in the gradient refrigeration module.

[0008] In some embodiments, the gradient refrigeration module adopts a variable volume closed structure, including:

[0009] A volume adjustment mechanism, configured to adjust the volume of a first chamber in the gradient refrigeration module for accommodating the refrigerant;

[0010] a pressure monitoring device, configured to monitor the working fluid pressure in the first chamber;

[0011] A temperature sensor array is configured to detect the temperature of the refrigerant and / or the cooled medium in the heat exchange field constructed by the gradient refrigeration module;

[0012] The temperature gradient control mechanism is configured to control the volume adjustment mechanism according to the detection data of the pressure monitoring device and the temperature sensor array so that the refrigerant is heated up and operated according to a preset curve and a corresponding relationship between saturation temperature and saturation pressure.

[0013] In some embodiments, the gradient refrigeration module adopts a multi-stage pressure control structure, which is used to analyze the continuous preset curve of the refrigerant in the refrigeration cycle into a discrete process composed of multiple evaporation heat absorption and adiabatic compression combinations, and control the refrigerant to heat up according to a multi-stage discrete process with a gradient relationship to run close to the preset curve.

[0014] In some embodiments, the gradient refrigeration module includes at least two evaporators and also includes the same number of compressors as the evaporators;

[0015] A compressor is connected behind each evaporator, and an evaporator and the compressor connected thereto form an evaporation-compression module. At least two evaporation-compression modules are connected in series and arranged between the outlet of the pressure reduction unit and the inlet of the heat release unit.

[0016] In some embodiments, the gradient refrigeration module includes at least two evaporators, the pressure reduction unit is a throttle valve having the same number as the evaporators, and the heat release unit is a condenser;

[0017] The inlet end of each throttle valve is connected to the outlet end of the condenser, and the outlet end of each throttle valve is connected to an evaporator. A throttling valve and the evaporator connected thereto form a throttling evaporation module, and the outlet steam of each throttling evaporation module is subjected to graded compression or coupled compression and then introduced into the inlet of the heat release unit.

[0018] In some embodiments, the throttling evaporation modules are sorted from high to low according to the pressure after throttling, and the throttling evaporation modules of each pressure level are connected to a compressor of the corresponding pressure level;

[0019] The lowest pressure steam generated by the throttling evaporation group of the lowest pressure level is connected to the inlet of the compressor of the lowest pressure level through a pipeline, and the steam generated by the throttling evaporation groups of other pressure levels merges with the outlet steam of the compressor of the corresponding pressure level of the throttling evaporation module of the lower pressure level, and then enters the inlet of the compressor of the corresponding pressure level, and the outlet steam of the compressor of the highest pressure level is connected to the condenser through a pipeline;

[0020] The heat exchange sequence between the cooled medium and the evaporators of each stage is from the highest pressure stage evaporator to the lowest pressure stage evaporator step by step.

[0021] In some embodiments, outlet steam of each throttling evaporation module is fed into a compressor in the form of a single gas source or multiple gas sources, and the outlet steam of the compressor is connected to a condenser through a pipeline.

[0022] In some embodiments, each of the throttling evaporation modules is connected to a corresponding compressor, and outlet steam of each of the compressors is connected to a condenser via a pipeline.

[0023] In some embodiments, the pressure reduction unit adopts a tapered nozzle structure to convert the pressure difference energy of the working fluid into kinetic energy.

[0024] In some embodiments, the gradient refrigeration module adopts a pressure diffuser structure, and the low-temperature and high-speed fluid generated by the pressure reducing device absorbs heat in the pressure diffuser structure while increasing the pressure and temperature.

[0025] In some embodiments, a boost device is also included, and the boost device uses a continuous cooling method to reduce compression power consumption.

[0026] In some embodiments, a boost device is also included, and the boost device uses a multi-stage cooling method to reduce compression power consumption.

[0027] In a second aspect, the present invention provides an operating method applied to the above-mentioned high-efficiency gradient refrigeration cycle system, comprising:

[0028] Determine an ideal temperature rise curve of the refrigerant in the gradient refrigeration module according to the temperature drop curve of the cooling medium during the cooling process, and set the ideal temperature rise curve as a preset curve;

[0029] Based on the characteristic curve of the heat absorption process of the refrigerant, the temperature gradient control mechanism is controlled to control the pressure increase process of the refrigerant to be close to the preset curve.

[0030] In some embodiments, including:

[0031] Real-time monitoring of the state parameters of the refrigerant and / or the cooled medium;

[0032] According to the structural characteristics of the refrigeration cycle system, the corresponding adjustment strategy is selected to dynamically optimize the heat transfer process.

[0033] In some embodiments, including:

[0034] Acquire state parameters through a multi-parameter real-time monitoring system and establish a multi-dimensional state space containing key parameters such as temperature, pressure, and flow rate;

[0035] Based on thermodynamic theory, the calculation of each link of the system loss, and perform dynamic optimization;

[0036] Adaptive control algorithm is used to automatically adjust system parameters according to load changes and environmental conditions, so that the deviation between the actual operating curve and the preset curve is less than the set threshold.

[0037] In some embodiments, including:

[0038] Determine the pressure boost requirement of the refrigerant from the outlet of the gradient cooling module to the inlet of the heat release unit, and determine the ideal pressure boost process line of the refrigerant with the goal of minimizing power consumption;

[0039] Taking the ideal boosting process line as the target line, the boosting process of the refrigerant is made close to the ideal boosting process line by controlling the cooling method, cooling medium, cooling temperature and cooling flow of the boosting device.

[0040] In some embodiments, the working fluid of the boosting device is steam, the steam at the inlet of the boosting device is in a saturated state, and the saturated steam line is selected as the ideal boosting process line.

[0041] In some embodiments, the working fluid of the boosting device is steam, the steam at the inlet of the boosting device is in a supersaturated state, the steam superheat is set, and a steam boosting curve with a specific steam superheat is selected as the ideal boosting process line.

[0042] Compared with the prior art, the present invention has at least the following beneficial effects:

[0043] 1. The present invention realizes dynamic matching of the temperature curves of the refrigerant and the cooled medium through a temperature gradient control mechanism, thereby greatly reducing irreversible losses in the heat transfer process;

[0044] 2. The use of a multi-stage pressure control structure or a variable volume closed structure, combined with a high-precision sensor array and an intelligent control system, enables the refrigerant to be accurately heated according to a preset curve, greatly improving the controllability and stability of the refrigeration process and meeting the needs of high-precision temperature control.

[0045] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] The present invention is further described using the accompanying drawings, but the embodiments in the accompanying drawings do not constitute any limitation to the present invention. A person skilled in the art can obtain other drawings based on the following drawings without creative work.

[0047] Figure 1 It is a schematic framework diagram of a high-efficiency gradient refrigeration cycle system under one implementation method in Example 1.

[0048] Figure 2It is a schematic framework diagram of a high-efficiency gradient refrigeration cycle system under another implementation method in Example 3.

[0049] Figure 3 It is a framework schematic diagram of a high-efficiency gradient refrigeration cycle system under an implementation method in Example 4.

[0050] Figure 4 It is a framework schematic diagram of a high-efficiency gradient refrigeration cycle system under another implementation method in Example 4.

[0051] Figure 5 This is a schematic diagram of the framework of a high-efficiency gradient refrigeration cycle system under another implementation method in Example 4.

[0052] Figure 6 It is a framework schematic diagram of a high-efficiency gradient refrigeration cycle system under an implementation method in Example 5. DETAILED DESCRIPTION

[0053] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0054] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, 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, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0055] In the description of the present invention, when it is described that a specific device is located between a first device and a second device, there may or may not be an intermediate device between the specific device and the first device or the second device. When it is described that a specific device is connected to other devices, the specific device may be directly connected to the other devices without an intermediate device, or may not be directly connected to the other devices but have an intermediate device.

[0056] Technologies, methods, and equipment known to ordinary technicians in the relevant art may not be discussed in detail, but where appropriate, the technologies, methods, and equipment should be considered as part of the specification.

[0057] Embodiment 1:

[0058] Reference Figure 1 , this embodiment 1 provides a high-efficiency gradient refrigeration cycle system, including a heat release unit 10, a pressure reduction unit 20 and a gradient refrigeration module 30;

[0059] A temperature gradient control mechanism is provided in the gradient refrigeration module 30. The temperature gradient control mechanism is configured to gradually increase the temperature of the refrigerant according to a preset curve during the heat absorption process, matching the temperature curve of the cooled medium to reduce heat transfer. damage.

[0060] It should be noted that in the traditional refrigeration cycle, the refrigerant maintains the saturated temperature under the saturated pressure for heat exchange, and there will be losses along the way during the operation of the refrigerant, resulting in pressure loss. Therefore, as the heat exchange proceeds, the actual saturated pressure of the refrigerant is constantly decreasing. That is to say, if the corresponding temperature of the saturated pressure of the refrigerant when entering the evaporation process is 8 degrees, and when the evaporation process ends, the corresponding temperature under the saturated pressure of its current state is 6 degrees, there will be a loss of 2 degrees. However, since the temperature of the cooled medium before and after the heat exchange is higher than that of the refrigerant, when the refrigerant further loses its evaporation temperature, the temperature difference between the refrigerant and the cooled medium will increase, making the heat exchange process Therefore, in this embodiment, during the heat absorption process of the refrigerant, the temperature gradient control mechanism is used to perform adaptive control, so that the temperature rise curve of the refrigerant is adapted to the temperature curve of the cooled medium, thereby reducing the temperature difference between the two. By gradually increasing the temperature of the refrigerant during the heat exchange process, a better heat transfer process is achieved to reduce the heat transfer. loss and improve heat transfer efficiency.

[0061] Preferably, the cooled medium forms a countercurrent heat exchange relationship with the refrigerant in the gradient refrigeration module 30, that is, in the heat exchange field constructed for the gradient refrigeration module 30, for example, the temperature of the cooled medium before heat exchange is 25 degrees, and the temperature after heat exchange is 15 degrees, the temperature of the refrigerant before heat exchange is 5 degrees, and the temperature after heat exchange is 15 degrees. Since it is a countercurrent heat exchange relationship, the cooled medium at 25 degrees corresponds to 15 degrees of the refrigerant, and the cooled medium at 15 degrees corresponds to 5 degrees of the refrigerant. It can be seen that no matter before or after heat exchange, the temperature difference between the cooled medium and the refrigerant is controlled at 10 degrees; this is equivalent to that, during the heat exchange process, when the temperature of the refrigerant gradually increases, it can better match the cooling curve of the cooled medium, reducing the temperature difference in the heat transfer process. A smaller heat transfer temperature difference means a smaller irreversible loss, thereby improving the thermodynamic efficiency of the system. The loss can be reduced and the input power required by the system can be reduced, thus achieving energy saving.

[0062] Optionally, the temperature rise process of the refrigerant is a process of dynamically matching the temperature curve of the cooled medium, and the temperature rise changes in a gradient.

[0063] Embodiment 2:

[0064] As an implementation mode, in this embodiment 2, the gradient cooling module 30 adopts a variable volume closed structure, including:

[0065] A volume adjustment mechanism, configured to adjust the volume of a first chamber in the gradient cooling module 30 for accommodating a refrigerant;

[0066] a pressure monitoring device configured to monitor the working fluid pressure in the first chamber;

[0067] The temperature sensor array is configured to detect the temperature of the refrigerant and / or the cooled medium in the heat exchange field constructed by the gradient refrigeration module 30;

[0068] The temperature gradient control mechanism is configured to control the volume adjustment mechanism to increase the temperature of the refrigerant according to a preset curve and a corresponding relationship between saturation temperature and saturation pressure based on the detection data of the pressure monitoring device and the temperature sensor array.

[0069] In actual operation, the volume adjustment mechanism can dynamically adjust the volume of the first chamber where the refrigerant is located according to the real-time data fed back by the pressure monitoring device and the temperature sensor array. By changing the volume, the pressure and temperature of the refrigerant are adjusted to achieve stable heating of the refrigerant according to the preset heating curve, while ensuring the correspondence between the saturation temperature and the saturation pressure. Specifically, when the pressure monitoring device detects a change in the working fluid pressure, the system will automatically adjust the temperature gradient control mechanism to optimize the heating path of the working fluid, thereby improving the refrigeration efficiency. The key beneficial effect of this technical solution is that it realizes fine control of the working fluid state, effectively reduces energy loss, and improves the adaptability and efficiency of the system.

[0070] In addition, as another embodiment, the gradient refrigeration module 30 adopts a multi-stage pressure control structure, which is used to analyze the continuous preset curve of the refrigerant in the refrigeration cycle into a discrete process composed of multiple evaporation heat absorption and adiabatic compression combinations, and control the refrigerant to heat up according to a multi-stage discrete process with a gradient relationship. The operation is close to the preset curve.

[0071] This embodiment adopts a multi-stage pressure control structure to analyze the continuous preset temperature rise curve of the refrigerant in the refrigeration cycle into multiple discrete processes of evaporation heat absorption and adiabatic compression. In specific implementation, the refrigerant undergoes an evaporation heat absorption process and a compression process at each stage, and multiple discrete processes are combined into a gradual temperature rise process. Each stage of evaporation and compression corresponds to a specific pressure and temperature change, so that the temperature rise process of the refrigerant is closer to the ideal preset curve. This multi-stage discrete control scheme can optimize the temperature rise path of the refrigerant at different stages, thereby improving the heat exchange efficiency, avoiding overcooling or temperature fluctuations common in traditional refrigeration methods, and thus reducing energy waste.

[0072] Embodiment 3:

[0073] Reference Figure 2 In the present embodiment 3, the gradient refrigeration module 30 includes at least two evaporators and also includes compressors having the same number as the evaporators;

[0074] A compressor is connected behind each evaporator, and an evaporator and the compressor connected thereto form an evaporation-compression module 40 . At least two evaporation-compression modules 40 are connected in series and arranged between the outlet of the pressure reduction unit 20 and the inlet of the heat release unit 10 .

[0075] Each evaporator cools the cooled medium through evaporative heat absorption, the refrigerant absorbs heat and evaporates, and the compressor compresses the evaporated gas to increase its energy density. This combined structure of the evaporation-compression module 40 can enable the refrigerant to release its refrigeration heat absorption capacity in multiple stages, and further optimize the refrigeration efficiency through the configuration of the series modules, ensuring that the refrigerant is evenly and stably heated during the heat exchange process. In each evaporation-compression module 40, adjustments can be made based on the operating difference between the actual temperature rise curve of the refrigerant and the ideal temperature rise curve, thereby improving the heat exchange efficiency of the overall system and reducing the compression power consumption and the energy required for refrigeration.

[0076] Optionally, the compressor in this embodiment is a variable capacity compressor or a twin-screw compressor. The variable capacity compressor can adjust its volume according to the change of the state of the working fluid (such as the change in the ratio of gas and liquid), so that it can effectively handle the mixture of liquid and gaseous working fluids during suction; the twin-screw compressor achieves compression through a rotating screw, has high volumetric efficiency and compression efficiency, and can effectively handle gas mixtures containing liquid working fluids; both variable capacity compressors and twin-screw compressors can accurately control the temperature rise during the compression process to avoid changes in the working fluid properties and energy losses caused by excessive temperature during the compression process, which is crucial to improving the efficiency of the overall refrigeration system. This type of compressor can achieve efficient compression and heating of vapor-liquid two-phase refrigerant, thereby improving the performance and energy efficiency of the entire high-efficiency gradient refrigeration cycle system.

[0077] Embodiment 4:

[0078] In this embodiment 4, the gradient refrigeration module 30 includes at least two evaporators, the pressure reduction unit 20 is a throttle valve with the same number as the evaporators, and the heat release unit 10 is a condenser;

[0079] The inlet end of each throttle valve is connected to the outlet end of the condenser, and the outlet end of each throttle valve is connected to an evaporator. A throttle valve and the evaporator connected thereto form a throttling evaporation module 50. The outlet steam of each throttling evaporation module 50 is subjected to graded compression or coupled compression and then introduced into the inlet of the heat release unit 10.

[0080] In a specific implementation, the throttle valve is used to adjust the flow and pressure of the refrigerant, converting the high-pressure refrigerant into low-pressure steam, and each evaporator lowers the temperature by absorbing heat through the steam behind the throttle valve. Optionally, the throttle valve is an electronic expansion valve, and the opening sizes of the electronic expansion valves corresponding to different throttling evaporation modules 50 are different, thereby causing different pressure drops, and the gradient change of the pressure after throttling forms a saturated evaporation temperature with a gradient heat exchange effect. This design can minimize the energy loss in the heat exchange process, optimize the temperature control effect of each stage through a multi-stage pressure distribution system, maximize the cooling effect of each evaporator, and thus improve the overall refrigeration efficiency.

[0081] Reference Figure 3 As an implementation method, a graded compression method is adopted. Specifically, the throttling evaporation modules 50 are sorted from high to low according to the pressure after throttling, and the throttling evaporation modules 50 of each pressure level are connected to a compressor of the corresponding pressure level;

[0082] like Figure 3 As shown, there are three levels of throttling evaporation modules 50 from top to bottom, wherein the topmost pressure level is the lowest, the middle is the second, and the bottommost pressure level is the highest; the lowest pressure steam generated by the throttling evaporation group of the lowest pressure level is connected to the inlet of the compressor of the lowest pressure level through a pipeline, and the compressor of the lowest pressure level is the first compression stage, and the steam generated by the throttling evaporation groups of other pressure levels merges with the outlet steam of the compressor of the corresponding pressure level of the throttling evaporation module 50 of the lower pressure level, and then enters the inlet of the compressor of the corresponding pressure level, and the outlet steam of the compressor of the highest pressure level is connected to the condenser through a pipeline; it is equivalent to compressing and heating the steam corresponding to the lowest pressure level first, and then merging the steam corresponding to the middle pressure level to compress and heat it, and finally merging the steam corresponding to the highest pressure level to compress and heat it, so as to form a graded compression;

[0083] The order of heat exchange between the cooled medium and each stage of evaporators is from the highest pressure stage evaporator to the lowest pressure stage evaporator step by step. The flow direction of the cooled medium is different from the compression direction of the refrigerant. The compression direction of the refrigerant is low at first and then high, while the flow direction of the cooled medium is high at first and then low.

[0084] The outlet steam of each throttling evaporation module 50 is arranged in sequence from high to low according to the pressure level, and is compressed step by step by compressors of different pressure levels. Each compressor is responsible for compressing the steam generated by the throttling evaporation module 50 to which it is connected, ensuring that the steam maintains a high energy density when entering the next stage. When the steam is compressed step by step between pressure levels, the energy conversion is more efficient, avoiding energy waste caused by uneven compression. This design can achieve more precise compression control, ensure that the temperature and pressure changes of the refrigerant are stable, and effectively improve the efficiency and stability of the entire system.

[0085] Reference Figure 4 As another implementation method, a coupled compression method is adopted. Specifically, the outlet steam of each throttling evaporation module is fed into a compressor in the form of a single gas source or multiple gas sources. The outlet steam of the compressor is connected to the condenser through a pipeline. One compressor is used to compress multiple gas sources, thereby improving the working efficiency of the compressor and reducing unnecessary compression devices in the system. This centralized compression method simplifies the system structure, improves the compression efficiency, reduces the size and cost of the equipment, and ensures that the refrigeration effect of the system is not affected.

[0086] Reference Figure 5 As another implementation method, a graded compression method is adopted. Specifically, each throttling evaporation module is connected to a corresponding compressor, and the outlet steam of each compressor is connected to the condenser through a pipeline. Each compressor can be controlled individually, and the steam at the outlet of each throttling evaporation module is compressed and heated. The compression and heating process required for each throttling evaporation module can be adjusted individually to achieve a relatively consistent refrigerant exhaust state at the condenser inlet. The steam generated by each module is processed by a special compressor. The outlet steam of each compressor is connected to the condenser through a pipeline, ensuring that the refrigeration capacity of each throttling evaporation module is maximized. In this way, the performance of each module can be optimized, and the adaptability of the system can be improved, so that it can handle more types of load changes and ensure efficient operation under different working conditions.

[0087] Embodiment 5:

[0088] Reference Figure 6 In this embodiment 5, the pressure reduction unit adopts a tapered nozzle structure 21 to convert the pressure difference energy of the working fluid into kinetic energy. Specifically, the design of the tapered nozzle accelerates the fluid through a gradually shrinking channel, so that the working fluid can flow at a high speed during the pressure reduction process, thereby enhancing the heat exchange efficiency. This design not only optimizes the flow characteristics of the working fluid, but also improves the heat absorption capacity of the working fluid, thereby reducing the overall energy consumption and improving the heat transfer performance of the system.

[0089] Preferably, the gradient refrigeration module adopts a pressure diffuser structure 31, and introduces the low-temperature high-speed fluid treated by the pressure reducing device into the pressure diffuser structure 31, so that the working fluid is heated while absorbing heat through pressure diffusion. The key feature of this structure is that it can absorb external heat and increase its pressure when the working fluid changes from low-speed flow to high-pressure, temperature-appropriate gas. This structure not only effectively absorbs the kinetic energy of the fluid and increases the temperature of the refrigerant, but also improves the refrigeration efficiency of the entire system and reduces the power consumption of the system.

[0090] Optionally, a boosting device 60 is further included, and the boosting device 60 adopts a continuous cooling method to reduce the compression power consumption. In specific implementation, the load of the compressor is reduced through the continuous cooling process, and the energy loss in the compression process is reduced. Continuous cooling allows the temperature of the compressed working fluid to be effectively controlled during the boosting process, avoiding energy waste caused by overheating, and ultimately improving the energy utilization rate and working stability of the entire system.

[0091] Optionally, a boosting device 60 is also included, and the boosting device 60 adopts a multi-stage cooling method to reduce compression power consumption. Each stage of the cooling device accurately controls the cooling temperature and flow rate to ensure that the temperature of the working fluid changes steadily during the multi-stage cooling process, and finally reaches the ideal boosting state. This multi-stage cooling not only effectively reduces energy loss, but also improves the overall stability and efficiency of the system, and is particularly suitable for refrigeration needs with large loads or long-term operation.

[0092] Embodiment 6:

[0093] In this embodiment 6, an operation method applied to the above-mentioned high-efficiency gradient refrigeration cycle system is provided, comprising:

[0094] According to the temperature drop curve of the cooling medium during the cooling process, determine the ideal temperature rise curve of the refrigerant in the gradient refrigeration module 30, and set the ideal temperature rise curve as the preset curve;

[0095] Based on the characteristic curve of the refrigerant heat absorption process, the temperature gradient control mechanism is controlled to control the refrigerant pressure boost process to be close to the ideal pressure boost process line, and the ideal pressure boost process line corresponds to the preset curve. Since in the refrigerant heat absorption process, according to the one-to-one correspondence between the saturated pressure and the saturated temperature, the preset curve and the ideal pressure boost process line are the only corresponding relationship, so controlling the refrigerant pressure boost process to be close to the preset curve is equivalent to controlling the refrigerant pressure boost process to be close to the ideal pressure boost process line.

[0096] In actual operation, generally speaking, the user has a target temperature. For example, the current room temperature is 35 degrees and needs to be adjusted to 25 degrees. There is a temperature difference of 10 degrees in between. That is, a temperature drop curve of the cooling process of the cooling medium will be formed. According to the ideal heat transfer temperature difference of 8 degrees, the ideal temperature rise curve of the refrigerant in the gradient refrigeration module 30 can be determined. For example, the refrigerant is 17 degrees before heat exchange and 27 degrees after heat exchange. The curve of the refrigerant heating from 17 degrees to 27 degrees is set as the preset curve.

[0097] Then, based on the heat absorption characteristics of the refrigerant, because the saturated pressure and the saturated temperature are in a one-to-one correspondence under the saturated state, the ideal pressure boost process line is also determined, and the corresponding relationship between the ideal pressure boost process line and the preset curve is determined. Through the precise control of the temperature, pressure and flow rate at each stage, it is ensured that the refrigerant can be heated in the optimal way during the heat absorption process, so as to perfectly match the cooling process of the cooled medium. In actual operation, the temperature sensor array and the real-time data monitoring system are used to track the temperature changes of the cooling medium, and at the same time, the flow state, pressure and flow rate of the refrigerant in the gradient refrigeration module 30 are adjusted to ensure that the heating process of the refrigerant is consistent with the set ideal curve. The control system adjusts the temperature gradient and the working state of the compression device in real time, dynamically adjusts the heating process, and adjusts the system operation state in real time to ensure that the refrigeration efficiency is maximized, reduce energy waste, and improve the overall refrigeration effect.

[0098] Specifically, it includes:

[0099] Real-time monitoring of the state parameters of the refrigerant and / or the cooled medium; as the system load changes, the heat absorption capacity of the refrigerant will also change, so dynamic adjustment is required to ensure the best heat transfer effect. Changes in environmental conditions (such as outdoor temperature, humidity, etc.) will also affect the operation of the system. Therefore, the use of real-time monitoring and dynamic optimization strategies can enable the system to maintain optimal performance under various changing conditions;

[0100] According to the structural characteristics of the refrigeration cycle system, the corresponding adjustment strategy is selected to dynamically optimize the heat transfer process.

[0101] The state parameters of the refrigerant and the cooled medium are monitored in real time through multi-dimensional state space, and appropriate adjustment strategies are selected according to the system characteristics. During the implementation process, the system will adjust the working parameters of each link according to real-time data, and use thermodynamic models to calculate energy losses. Based on this information, the control system will automatically adjust the refrigerant flow rate, pressure, volume and other parameters to optimize the heat exchange process, ensure that parameters such as temperature and pressure are always in the optimal operating range, thereby improving the refrigeration efficiency and effectively responding to operational changes under different loads and environmental conditions.

[0102] Furthermore, it includes:

[0103] Acquire state parameters through a multi-parameter real-time monitoring system and establish a multi-dimensional state space containing key parameters such as temperature, pressure, and flow rate;

[0104] Based on thermodynamic theory, the calculation of each link of the system loss, and perform dynamic optimization;

[0105] Adaptive control algorithm is used to automatically adjust system parameters according to load changes and environmental conditions, so that the deviation between the actual operating curve and the preset curve is less than the set threshold.

[0106] The state parameters in the system are monitored in real time through multi-dimensional state space, and the energy loss of each link is calculated based on thermodynamic theory, and dynamic optimization is performed; the control system first collects data from various sensors (such as temperature, pressure, flow, etc.), and then calculates the energy loss of each link based on thermodynamics. Through the adaptive control algorithm, the system can automatically adjust according to load changes and environmental conditions, thereby reducing the deviation from the preset curve, improving the stability and efficiency of operation, and ensuring that the system can maintain efficient operation under different loads.

[0107] Furthermore, it includes:

[0108] Determine the pressure boost requirement of the refrigerant from the outlet of the gradient refrigeration module 30 to the inlet of the heat release unit 10, and determine the ideal pressure boost process line of the refrigerant with the goal of minimizing power consumption;

[0109] Taking the ideal pressure boosting process line as the target line, the pressure boosting process of the refrigerant is made close to the ideal pressure boosting process line by controlling the cooling method, cooling medium, cooling temperature and cooling flow rate of the pressure boosting device 60 .

[0110] During the compression process of the refrigerant, there will be a certain amount of energy loss, so the ideal boost process line can minimize this loss. By setting the ideal boost curve, the system can more accurately control the temperature rise process of the refrigerant, ensure the compressor's operating efficiency is maximized, and reduce power consumption. During implementation, the boost device 60 first calculates the ideal boost process line based on the initial state of the refrigerant (such as the steam saturation state). Then, the control system optimizes the boost process of the refrigerant by adjusting the temperature, flow rate, and cooling method of the cooling medium to ensure that the process is close to this ideal boost curve.

[0111] As an implementation method, the working medium of the boosting device 60 is steam, the steam at the inlet of the boosting device 60 is in a saturated state, and the saturated steam line is selected as the ideal boosting process line. In the saturated steam state, the temperature and pressure of the steam are stable. Selecting the saturated steam line as the boosting process line can ensure the stability of the steam heating process, reduce energy loss, and maintain efficient operation of the compressor. In actual operation, the boosting device 60 will set the boosting process line according to the saturated state of the working medium steam, and control the cooling system according to this process line to ensure that the steam always remains in an ideal state during the boosting process.

[0112] As another embodiment, the working fluid of the boosting device 60 is steam, the steam at the inlet of the boosting device 60 is in a supersaturated state, the steam superheat is set, and a steam boost curve with a specific steam superheat is selected as the ideal boost process line. Supersaturated steam has higher thermal energy and can perform heat exchange more efficiently. During the boosting process, selecting a boost curve with a specific superheat can further optimize the compression process and improve the working efficiency of the compressor. In implementation, the control system will set the superheat according to the initial state of the working fluid, and select a suitable boost curve. By adjusting the cooling temperature and flow rate, the boost process of the working fluid meets the set ideal boost curve, thereby achieving optimal energy efficiency.

[0113] It should be noted that the boosting device in the above embodiments also includes a compressor, which is not distinguished here.

[0114] In summary, compared with the prior art, the above embodiments have at least the following technical advantages:

[0115] High efficiency of heat exchange: This system uses the temperature gradient control mechanism in the gradient refrigeration module 30 to gradually increase the temperature of the refrigerant according to the preset curve during the heat absorption process, accurately matching the temperature change of the cooled medium. The design of the countercurrent heat exchange relationship ensures a larger heat exchange area and a smaller temperature difference, thereby significantly improving the overall heat exchange efficiency.

[0116] Dynamically optimized operation capability: This system can monitor the state parameters of the refrigerant and the cooled medium in real time, and dynamically optimize the heat transfer process based on these data. Compared with traditional systems, this method improves the adaptability and response speed of the system, ensuring that the system can still operate stably and efficiently under the influence of load changes and environmental conditions.

[0117] Reduce energy consumption: By setting the ideal temperature rise curve and the ideal pressure rise process line, the system can optimize the compression and cooling process and reduce unnecessary energy consumption. At the same time, the design of using saturated steam and supersaturated steam further improves the compression efficiency and reduces the power consumption of the system.

[0118] Innovation of multi-stage pressure control structure: The multi-stage pressure control structure is used to decompose the temperature rise process of the refrigerant into multiple discrete processes of evaporation heat absorption and adiabatic compression, thereby achieving refined control and avoiding the problems of temperature fluctuation and energy loss in traditional refrigeration methods.

[0119] The above-mentioned embodiments are only preferred embodiments of the present invention and cannot be used to limit the scope of protection of the present invention. Any non-substantial changes and substitutions made by technicians in this field on the basis of the present invention shall fall within the scope of protection required by the present invention.

Claims

1. A high-efficiency gradient refrigeration cycle system, characterized in that: It includes a heat release unit, a pressure reduction unit and a gradient cooling module; The gradient refrigeration module is provided with a temperature gradient control mechanism, which is configured to gradually increase the temperature of the refrigerant according to a preset curve during the heat absorption process, matching the temperature curve of the cooled medium to reduce heat transfer. damage.

2. A high-efficiency gradient refrigeration cycle system according to claim 1, characterized in that: The cooled medium forms a countercurrent heat exchange relationship with the refrigerant in the gradient refrigeration module.

3. A high-efficiency gradient refrigeration cycle system as claimed in claim 1 or 2, characterized in that: The gradient refrigeration module adopts a variable volume closed structure, including: A volume adjustment mechanism, configured to adjust the volume of a first chamber in the gradient refrigeration module for accommodating the refrigerant; a pressure monitoring device, configured to monitor the working fluid pressure in the first chamber; A temperature sensor array is configured to detect the temperature of the refrigerant and / or the cooled medium in the heat exchange field constructed by the gradient refrigeration module; The temperature gradient control mechanism is configured to control the volume adjustment mechanism according to the detection data of the pressure monitoring device and the temperature sensor array so that the refrigerant is heated up and operated according to a preset curve and a corresponding relationship between saturation temperature and saturation pressure.

4. A high-efficiency gradient refrigeration cycle system as claimed in claim 1 or 2, characterized in that: The gradient refrigeration module adopts a multi-stage pressure control structure, which is used to analyze the continuous preset curve of the refrigerant in the refrigeration cycle into a discrete process composed of multiple evaporation heat absorption and adiabatic compression combinations, and control the refrigerant to heat up according to a temperature close to the preset curve through the multi-stage discrete process with a gradient relationship.

5. A high-efficiency gradient refrigeration cycle system as claimed in claim 4, characterized in that: The gradient refrigeration module comprises at least two evaporators and also comprises compressors having the same number as the evaporators; A compressor is connected behind each evaporator, and an evaporator and the compressor connected thereto form an evaporation-compression module. At least two evaporation-compression modules are connected in series and arranged between the outlet of the pressure reduction unit and the inlet of the heat release unit.

6. A high-efficiency gradient refrigeration cycle system as claimed in claim 4, characterized in that: The gradient refrigeration module comprises at least two evaporators, the pressure reduction unit is a throttle valve having the same number as the evaporators, and the heat release unit is a condenser; The inlet end of each throttle valve is connected to the outlet end of the condenser, and the outlet end of each throttle valve is connected to an evaporator. A throttling valve and the evaporator connected thereto form a throttling evaporation module, and the outlet steam of each throttling evaporation module is subjected to graded compression or coupled compression and then introduced into the inlet of the heat release unit.

7. A high-efficiency gradient refrigeration cycle system as claimed in claim 6, characterized in that: The throttling evaporation modules are arranged in descending order according to the pressure after throttling, and the throttling evaporation modules of each pressure level are connected to a compressor of the corresponding pressure level; The lowest pressure steam generated by the throttling evaporation group of the lowest pressure level is connected to the inlet of the compressor of the lowest pressure level through a pipeline, and the steam generated by the throttling evaporation groups of other pressure levels merges with the outlet steam of the compressor of the corresponding pressure level of the throttling evaporation module of the lower pressure level, and then enters the inlet of the compressor of the corresponding pressure level, and the outlet steam of the compressor of the highest pressure level is connected to the condenser through a pipeline; The heat exchange sequence between the cooled medium and the evaporators of each stage is from the highest pressure stage evaporator to the lowest pressure stage evaporator step by step.

8. A high-efficiency gradient refrigeration cycle system as claimed in claim 6, characterized in that: The outlet steam of each throttling evaporation module is collected into a compressor in the form of a single gas source or multiple gas sources, and the outlet steam of the compressor is connected to the condenser through a pipeline.

9. A high-efficiency gradient refrigeration cycle system as claimed in claim 6, characterized in that: Each of the throttling evaporation modules is connected to a corresponding compressor, and the outlet steam of each of the compressors is connected to a condenser via a pipeline.

10. A high-efficiency gradient refrigeration cycle system according to claim 1 or 2, characterized in that: The pressure reduction unit adopts a tapered nozzle structure to convert the pressure difference energy of the working fluid into kinetic energy.

11. A high-efficiency gradient refrigeration cycle system according to claim 10, characterized in that: The gradient refrigeration module adopts a pressure diffusion structure, and the low-temperature high-speed fluid generated by the pressure reduction device absorbs heat in the pressure diffusion structure while increasing the pressure and temperature.

12. A high-efficiency gradient refrigeration cycle system according to claim 11, characterized in that: It also includes a boosting device, which uses a continuous cooling method to reduce compression power consumption.

13. A high-efficiency gradient refrigeration cycle system according to claim 11, characterized in that: It also includes a boosting device, which adopts a multi-stage cooling method to reduce compression power consumption.

14. An operating method for a high-efficiency gradient refrigeration cycle system according to any one of claims 1 to 13, characterized in that: include: Determine an ideal temperature rise curve of the refrigerant in the gradient refrigeration module according to the temperature drop curve of the cooling medium during the cooling process, and set the ideal temperature rise curve as a preset curve; Based on the characteristic curve of the heat absorption process of the refrigerant, the temperature gradient control mechanism is controlled to control the pressure increase process of the refrigerant to be close to the preset curve.

15. The operating method according to claim 14, characterized in that: include: Real-time monitoring of the state parameters of the refrigerant and / or the cooled medium; According to the structural characteristics of the refrigeration cycle system, the corresponding adjustment strategy is selected to dynamically optimize the heat transfer process.

16. The operating method according to claim 15, characterized in that: include: Acquire state parameters through a multi-parameter real-time monitoring system and establish a multi-dimensional state space containing key parameters such as temperature, pressure, and flow rate; Based on thermodynamic theory, the calculation of each link of the system loss, and perform dynamic optimization; Adaptive control algorithm is used to automatically adjust system parameters according to load changes and environmental conditions, so that the deviation between the actual operating curve and the preset curve is less than the set threshold.

17. The operating method according to claim 15, characterized in that: include: Determine the pressure boost requirement of the refrigerant from the outlet of the gradient cooling module to the inlet of the heat release unit, and determine the ideal pressure boost process line of the refrigerant with the goal of minimizing power consumption; Taking the ideal boosting process line as the target line, the boosting process of the refrigerant is made close to the ideal boosting process line by controlling the cooling method, cooling medium, cooling temperature and cooling flow of the boosting device.

18. The operating method according to claim 17, characterized in that: The working medium of the boosting device is steam, the steam at the inlet of the boosting device is in a saturated state, and the saturated steam line is selected as the ideal boosting process line.

19. The operating method according to claim 17, characterized in that: The working medium of the boosting device is steam, the steam at the inlet of the boosting device is in a supersaturated state, the steam superheat is set, and a steam boosting curve with a specific steam superheat is selected as an ideal boosting process line.

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