Vehicle LNG (Liquefied Natural Gas) cold energy recovery system and vehicle

Abstract

The invention relates to the technical field of refrigeration equipment, in particular to a vehicle LNG cold energy recovery system and a vehicle, and aims to solve the problem that cold energy released in the LNG gasification process of an existing vehicle cannot be effectively recycled. In order to achieve the purpose, the automotive LNG cold energy recovery system comprises an LNG flow path and a refrigeration circulation loop, the LNG flow path is sequentially connected with an LNG storage tank, a first pump and a heat exchanger, the first pump is used for pumping out LNG from the LNG storage tank and conveying the LNG to the heat exchanger, and the LNG can release cold energy when flowing through the heat exchanger; the refrigerating circulation loop comprises a secondary refrigerant box, a second pump, a heat exchanger and at least one cold using module which are sequentially connected through pipelines to form a loop, the second pump is used for conveying a secondary refrigerant in the secondary refrigerant box to sequentially flow through the heat exchanger and the cold using module, and the secondary refrigerant can be cooled by the cold released by the LNG when flowing through the heat exchanger. And the cold energy released by the LNG is transferred to the cold using module through the heat exchanger, so that the utilization efficiency of energy is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of refrigeration equipment, and particularly provides a vehicle LNG cold energy recovery system and a vehicle. BACKGROUND

[0002] Liquefied natural gas (LNG) as a clean energy has been increasingly widely used in the field of heavy trucks, long-distance buses and other vehicles. LNG is usually stored in the form of low-temperature liquid at about -162℃ in a storage tank, and when used, it needs to be heated by a gasifier to change into gaseous natural gas at normal temperature, which can be supplied to the engine for combustion.

[0003] At present, the LNG gasification process on the vehicle usually relies on engine circulating coolant or ambient air as a heat source. In this gasification process, the huge amount of cold energy contained in LNG is directly released to the environment, causing significant waste of cold energy. This not only is an inefficient use of energy, but also is contrary to the current development trend of the automobile industry to pursue energy saving and emission reduction.

[0004] The vehicle itself is a comprehensive platform integrating multiple cold demand requirements. For example, the air conditioning system of the cab or passenger compartment, the vehicle refrigerator for preserving food and beverages for the driver, etc., all need to consume additional energy to produce cold energy. The traditional solution is to rely on an engine-driven compressor refrigeration system or an independent electric refrigeration device, which undoubtedly increases the load of the engine or the power consumption of the vehicle, resulting in additional fuel or gas consumption and more carbon emissions.

[0005] Therefore, how to efficiently and reliably recover and utilize the huge amount of cold energy released in the LNG gasification process of the vehicle, turning waste into treasure, has become a key technical problem to be solved in the field. SUMMARY

[0006] The present application aims to solve the above technical problems, i.e., to solve the problem that the cold energy released in the LNG gasification process of the existing vehicle cannot be effectively recovered and utilized.

[0007] In a first aspect, the present application provides a vehicle LNG cold energy recovery system, comprising an LNG flow path and a refrigeration cycle circuit, The LNG flow path is sequentially connected with an LNG storage tank, a first pump and a heat exchanger, the first pump being used to pump LNG out of the LNG storage tank and deliver it to the heat exchanger, and the LNG being capable of releasing cold energy when flowing through the heat exchanger; The refrigeration cycle circuit comprises a carrier tank, a second pump, the heat exchanger and at least one cold use module connected in sequence by pipelines to form a loop, the second pump being used to deliver the carrier in the carrier tank to sequentially flow through the heat exchanger and the cold use module, and the carrier being capable of being cooled by the cold energy released by the LNG when flowing through the heat exchanger.

[0008] In the preferred technical solution of the above-mentioned vehicle LNG cold energy recovery system, a cold storage module is also provided in the refrigeration cycle loop. The cold storage module is used to store cold energy when the LNG flow path is running and to release cold energy to the refrigerant when the LNG flow path stops running.

[0009] In the preferred technical solution of the above-mentioned vehicle LNG cold energy recovery system, the cold storage module is a cold storage device, and the cold storage device is provided with a groove, which is filled with a phase change material. The phase change material is used to store and release cold energy.

[0010] In the preferred technical solution of the above-mentioned vehicle LNG cold energy recovery system, the cooling module includes a vehicle refrigerator, the vehicle refrigerator includes a first evaporator for cooling the freezer compartment and a second evaporator for cooling the refrigerator compartment, and a flow switching component is provided on the refrigeration cycle loop. The flow switching component is configured to connect the first evaporator and the second evaporator in series or in parallel to the refrigeration cycle loop.

[0011] In the preferred technical solution of the above-mentioned vehicle LNG cold energy recovery system, the flow path switching component includes a first three-way valve and a second three-way valve; The inlet of the first three-way valve is connected to the refrigerant outlet of the heat exchanger, the first outlet of the first three-way valve is connected to the inlet of the first evaporator, and the second outlet of the first three-way valve is connected to the inlet of the second evaporator. The inlet of the second three-way valve is connected to the outlet of the first evaporator, the first outlet of the second three-way valve is connected to the inlet of the first evaporator, and the second outlet of the second three-way valve merges with the outlet of the second evaporator and is then connected to the inlet of the refrigerant tank.

[0012] In the preferred embodiment of the above-mentioned LNG cold energy recovery system for vehicles, the system further includes a control unit and multiple temperature sensors disposed in the refrigerator compartment and the freezer compartment. Both the first three-way valve and the second three-way valve are electromagnetic three-way valves. The control unit is configured to switch the series / parallel connection mode between the first evaporator and the second evaporator by controlling the first three-way valve and the second three-way valve based on the signal from the temperature sensor, and / or The control unit is configured to adjust the opening of the first three-way valve and the second three-way valve in parallel mode according to the signal from the temperature sensor to distribute the refrigerant flow into the first evaporator and the second evaporator.

[0013] In the preferred technical solution of the above-mentioned LNG cooling capacity recovery system for vehicles, the refrigerant is one of ethylene glycol aqueous solution, propylene glycol aqueous solution, or calcium chloride aqueous solution.

[0014] In the preferred technical solution of the above-mentioned vehicle LNG cold energy recovery system, the LNG flow path is split into a main path and a branch path downstream of the first pump. The heat exchanger is set on the branch path, and an LNG vaporizer is set on the main path. After the LNG in the branch path flows through the heat exchanger, it merges with the LNG in the main path downstream of the LNG vaporizer and flows together to the LNG engine.

[0015] In the preferred technical solution of the above-mentioned vehicle LNG cold energy recovery system, a third three-way valve is provided in the LNG flow path, and the third three-way valve divides the LNG flow path into the main path and the branch path.

[0016] In a second aspect, the present invention also provides a vehicle comprising the LNG cold energy recovery system for vehicles described in any of the preceding claims.

[0017] Those skilled in the art will understand that the technical solution of the present invention provides an LNG cold energy recovery system for vehicles, including an LNG flow path and a refrigeration cycle loop. The LNG flow path is sequentially connected to an LNG storage tank, a first pump, and a heat exchanger. The first pump pumps LNG from the LNG storage tank and delivers it to the heat exchanger, where the LNG releases cold energy as it flows through the heat exchanger. The refrigeration cycle loop includes a refrigerant tank, a second pump, a heat exchanger, and at least one cooling module, all connected in sequence via pipelines. The second pump delivers refrigerant from the refrigerant tank through the heat exchanger and the cooling module, where the refrigerant is cooled by the cold energy released by the LNG as it flows through the heat exchanger. By adopting the above technical solution, the present invention can solve the problem that the cold energy released during the LNG vaporization process in existing vehicles cannot be effectively recovered and utilized. Specifically, the cold energy released during LNG vaporization is transferred to the refrigerant through the heat exchanger, and the cold energy in the refrigerant is then transferred to the cooling module. Thus, the waste cold energy in the LNG flow path can be effectively converted into valuable cooling capacity, improving energy utilization efficiency.

[0018] Furthermore, the refrigeration cycle loop of the present invention is also equipped with a cold storage module. The cold storage module is used to store cold energy during the operation of the LNG flow path and release cold energy to the refrigerant when the LNG flow path stops operating. Through this setting, it is ensured that the cooling module can continuously obtain the required cold energy and maintain normal operation, and there will be no shutdown of the cooling equipment due to the interruption of the LNG flow path, which greatly improves the stability and reliability of the entire cold energy recovery system.

[0019] Furthermore, the cooling module of the present invention includes a vehicle-mounted refrigerator, which includes a first evaporator for cooling the freezer compartment and a second evaporator for cooling the refrigerator compartment. A flow switching component is provided on the refrigeration cycle loop, and the flow switching component is configured to connect the first evaporator and the second evaporator to the refrigeration cycle loop in series or in parallel. Through this configuration, the flow switching component enables the system to flexibly adapt to different cooling load conditions in the freezer and refrigerator compartments. This flexibility allows the vehicle-mounted refrigerator to better adapt to various usage scenarios, improving the practicality and reliability of the system. Attached Figure Description

[0020] The preferred embodiments of the present invention are described below with reference to the accompanying drawings, in which: Figure 1 This is a schematic diagram of the LNG cold energy recovery system for vehicles according to the present invention.

[0021] List of reference numerals in the attached diagram: 1. LNG flow path; 11. LNG storage tank; 12. First pump; 13. Heat exchanger; 14. LNG vaporizer; 15. Third three-way valve; 16. LNG engine; 2. Refrigeration cycle loop; 21. Refrigerant tank; 22. Second pump; 231. First evaporator; 232. Second evaporator; 241. First three-way valve; 242. Second three-way valve; 3. Cold storage module. Detailed Implementation

[0022] Preferred embodiments of the present invention will now be described with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are merely illustrative of the technical principles of the invention and are not intended to limit the scope of protection of the invention. For example, although the following embodiments are described in conjunction with LNG vehicles, the LNG cold energy recovery system for vehicles provided by the present invention is equally applicable to other products where the cold energy released during LNG vaporization cannot be effectively recovered and utilized.

[0023] It should be noted that, in the description of this invention, unless otherwise explicitly specified and limited, the terms "set" and "connection" should be interpreted broadly, for example, they can refer to a fixed connection, a detachable connection, or an integral connection. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0024] Based on the background art, there is a problem that the cold energy released during the LNG vaporization process in existing vehicles cannot be effectively recovered and utilized. This invention provides an LNG cold energy recovery system for vehicles, which aims to effectively solve the problem of ineffective recovery and utilization of the cold energy released during LNG vaporization by setting up a heat exchanger to transfer the cold energy generated during LNG vaporization to other circulation loops requiring cooling.

[0025] like Figure 1 As shown, the present invention provides an LNG cold energy recovery system for vehicles, including an LNG flow path 1 and a refrigeration cycle loop 2. The LNG flow path 1 is sequentially connected to an LNG storage tank 11, a first pump 12, and a heat exchanger 13. The first pump 12 is used to pump LNG from the LNG storage tank 11 and deliver it to the heat exchanger 13. The LNG can release cold energy when flowing through the heat exchanger 13. The refrigeration cycle loop includes a refrigerant tank 21, a second pump 22, a heat exchanger 13, and at least one cooling module connected in sequence through pipelines. The second pump 22 is used to deliver the refrigerant in the refrigerant tank 21 to flow sequentially through the heat exchanger 13 and the cooling module. The refrigerant can be cooled by the cold energy released by the LNG when flowing through the heat exchanger 13.

[0026] LNG flow path 1 is sequentially connected to an LNG storage tank 11, a first pump 12, and a heat exchanger 13. Its operation is as follows: LNG is stored in the LNG storage tank 11. The first pump 12 is responsible for pumping the LNG from the tank and delivering it to the heat exchanger 13. When the LNG flows through the heat exchanger 13, it releases cooling energy. This is the source of cooling energy for the entire cooling recovery system. LNG itself possesses a large amount of usable cooling energy during the vaporization process, which can be transferred to other media through the heat exchanger 13.

[0027] The refrigeration cycle loop includes a refrigerant tank 21, a second pump 22, a heat exchanger 13, and at least one cooling module, all connected sequentially by piping. The operation is as follows: the second pump 22 delivers refrigerant from the refrigerant tank 21, allowing it to flow sequentially through the heat exchanger 13 and the cooling module. As the refrigerant flows through the heat exchanger 13, it is cooled by the LNG release. The cooled refrigerant then flows through the cooling module, providing the necessary cooling capacity and achieving efficient utilization of the cooling energy. It should be noted that the cooling module can be configured according to actual needs, such as a vehicle's air conditioning system or a refrigerated storage unit requiring low-temperature preservation of goods.

[0028] Therefore, this invention, through its vehicle-mounted LNG cold energy recovery system, recovers and reuses the cold energy that would otherwise be wasted during the LNG vaporization process in the vehicle. The cold energy released from the LNG is delivered to the cooling module via heat exchanger 13, improving energy utilization efficiency, reducing energy waste, and aligning with the current trend of energy conservation and emission reduction.

[0029] For example, the heat exchanger 13 in this invention can be a shell-and-tube heat exchanger 13, a plate heat exchanger 13, a microchannel heat exchanger 13, etc. This invention does not specifically limit the type of heat exchanger 13.

[0030] Preferably, such as Figure 1 As shown, the refrigeration module includes a vehicle refrigerator, which includes a first evaporator 231 for cooling the freezer compartment and a second evaporator 232 for cooling the refrigerator compartment. A flow switching component is provided on the refrigeration cycle loop, and the flow switching component is configured to connect the first evaporator 231 and the second evaporator 232 to the refrigeration cycle loop in series or in parallel.

[0031] This invention incorporates two evaporators inside the vehicle refrigerator: a first evaporator 231 for cooling the freezer compartment and a second evaporator 232 for cooling the refrigerator compartment. The evaporator is a key component of the refrigeration system; the refrigerant absorbs heat in the evaporator to achieve the cooling effect. The freezer compartment requires a lower temperature to preserve items that need deep freezing, such as meat and ice cream; the refrigerator compartment is used to preserve items that require low temperatures but not deep freezing, such as vegetables, fruits, and beverages. By using two evaporators with different functions, the freezer and refrigerator compartments can be independently and precisely controlled.

[0032] When the first evaporator 231 and the second evaporator 232 are connected in series in the refrigeration cycle loop, the refrigerant flows through the first evaporator 231 and the second evaporator 232 in sequence. In this case, the refrigerant first absorbs heat from the freezer compartment in the first evaporator 231, causing the freezer compartment temperature to decrease and the refrigerant temperature to increase. Then it flows into the second evaporator 232 to further absorb heat from the refrigerator compartment.

[0033] Therefore, by connecting the series, the low temperature requirement of the freezer compartment (such as -18°C) can be guaranteed first. The refrigerant flowing out of the freezer compartment has been heated and then used to maintain the low temperature of the refrigerator compartment (such as 0-4°C). This achieves the cascade utilization of cold energy, which is highly efficient and the system structure is relatively simple.

[0034] When connected in parallel, the refrigerant flows simultaneously into the first evaporator 231 and the second evaporator 232. This allows the freezer and refrigerator compartments to independently receive cooling from the refrigerant, enabling more precise temperature control based on their respective cooling requirements. For example, when the freezer requires a large amount of cooling while the refrigerator requires less, the refrigerant flow rates into the two evaporators can be adjusted separately to meet different refrigeration needs.

[0035] Therefore, the flow switching component allows the system to flexibly adapt to the different cooling loads of the freezer and refrigerator compartments. In actual use, the quantity and type of items in the freezer and refrigerator compartments may change at any time, resulting in different cooling requirements. When the freezer compartment is filled with a large number of items that need to be frozen, the evaporator connection method can be adjusted to a method more suitable for centralized cooling (such as series connection or adjusting the flow distribution when connected in parallel) to meet the large cooling demand of the freezer compartment; conversely, when the refrigerator compartment requires more cooling, corresponding adjustments can also be made. This flexibility allows the vehicle refrigerator to better adapt to various usage scenarios, improving the system's practicality and reliability.

[0036] Preferably, such as Figure 1 As shown, the flow path switching assembly includes a first three-way valve 241 and a second three-way valve 242; the inlet of the first three-way valve 241 is connected to the refrigerant outlet of the heat exchanger 13, the first outlet of the first three-way valve 241 is connected to the inlet of the first evaporator 231, and the second outlet of the first three-way valve 241 is connected to the inlet of the second evaporator 232; the inlet of the second three-way valve 242 is connected to the outlet of the first evaporator 231, the first outlet of the second three-way valve 242 is connected to the inlet of the first evaporator 231, and the second outlet of the second three-way valve 242 and the outlet of the second evaporator 232 merge and are connected to the inlet of the refrigerant tank 21.

[0037] When the first evaporator 231 and the second evaporator 232 need to be connected in series in the refrigeration cycle loop, this can be achieved by controlling the first three-way valve 241 and the second three-way valve 242. For example, the first three-way valve 241 can be adjusted to allow the refrigerant to flow from the heat exchanger 13 into the first evaporator 231, while the second three-way valve 242 can be adjusted to allow the refrigerant flowing from the first evaporator 231 into the second evaporator 232. In this way, the refrigerant will flow sequentially through the first evaporator 231 and the second evaporator 232, achieving series refrigeration. This series connection method is suitable for situations where centralized cooling is required and the cooling demand of the freezer and refrigerator compartments is not significantly different.

[0038] To connect the first evaporator 231 and the second evaporator 232 in parallel, the first three-way valve 241 can be adjusted to allow the refrigerant to flow to both evaporators. Simultaneously, the second three-way valve 242 controls the refrigerant flowing from the two evaporators to converge and return to the refrigerant tank 21. In parallel mode, the freezer and refrigerator compartments can independently receive cooling from the refrigerant, allowing for more precise temperature control based on their respective cooling requirements.

[0039] Preferably, the vehicle LNG cooling capacity recovery system further includes a control unit (not shown in the figure) and multiple temperature sensors (not shown in the figure) disposed in the refrigerator compartment and the freezer compartment. The first three-way valve 241 and the second three-way valve 242 are both electromagnetic three-way valves. The control unit is configured to switch the series / parallel connection mode between the first evaporator 231 and the second evaporator 232 by controlling the first three-way valve 241 and the second three-way valve 242 according to the signal of the temperature sensor. The control unit is also configured to adjust the opening degree of the first three-way valve 241 and the second three-way valve 242 in parallel mode according to the signal of the temperature sensor to distribute the refrigerant flow into the first evaporator 231 and the second evaporator 232.

[0040] The electromagnetic three-way valve features fast response and high control precision. It can precisely control the valve opening and flow direction through electromagnetic signals, thereby enabling flexible switching of the refrigerant flow path.

[0041] The control unit determines the difference between the actual temperature and the set temperature in the refrigerator and freezer compartments based on signals from the temperature sensors. When centralized cooling is required or the temperature difference between the two compartments is small, the control unit sends a control signal to activate the first three-way valve 241 and the second three-way valve 242, switching the first evaporator 231 and the second evaporator 232 into series mode, allowing the refrigerant to flow through the two evaporators sequentially. When independent and precise temperature control is required for the two compartments, the control unit switches the evaporators into parallel mode, allowing the refrigerant to flow into the two evaporators separately. This automated control method requires no frequent manual intervention and can make timely adjustments based on actual temperature conditions, ensuring that the refrigerator and freezer compartments remain within the set temperature range, greatly improving the accuracy of temperature control.

[0042] In parallel mode, the control unit continues to analyze the temperature changes in the refrigerator and freezer compartments in real time based on the signals from the temperature sensors. If the freezer compartment temperature is higher and more cooling capacity is needed, the control unit adjusts the opening of the first three-way valve 241 and the second three-way valve 242 to increase the refrigerant flow into the first evaporator 231; conversely, if the refrigerator compartment temperature is higher, the refrigerant flow into the second evaporator 232 is increased to achieve a reasonable distribution of refrigerant between the two evaporators. This dynamic flow adjustment method based on actual needs can more efficiently utilize the cooling capacity released by LNG, reduce system energy consumption, and improve the overall energy efficiency of the vehicle LNG cooling capacity recovery system.

[0043] Preferably, such as Figure 1As shown, LNG flow path 1 is split into a main path and a branch path downstream of the first pump 12. Heat exchanger 13 is installed on the branch path, and LNG vaporizer 14 is installed on the main path. After the LNG in the branch path flows through the heat exchanger 13, it merges with the LNG in the main path downstream of the LNG vaporizer 14 and flows together to the LNG engine 16.

[0044] By splitting the LNG flow path 1 and setting up a dedicated branch for the LNG to flow through heat exchanger 13, the large amount of cooling energy carried by the LNG itself can be fully recovered. In conventional systems, this cooling energy may be wasted as the LNG vaporizes. However, in this optimized design, the LNG in the branch exchanges heat with the refrigerant in heat exchanger 13, transferring its cooling energy to the refrigerant for refrigeration in the cold storage and freezer compartments, greatly improving energy utilization efficiency and reducing system energy consumption.

[0045] The LNG vaporizer 14 in the main pipeline converts liquid LNG into gaseous LNG, providing a stable fuel supply for the LNG engine 16. Simultaneously, the LNG processed by the heat exchanger 13 in the branch pipeline merges with the main pipeline LNG downstream of the vaporizer, further regulating the temperature and pressure of the mixed LNG. This design ensures that the LNG engine 16 receives gaseous fuel in the appropriate state under different operating conditions, avoiding problems such as unstable combustion and power reduction caused by excessively low or high LNG temperatures, thus improving the operational reliability and efficiency of the LNG engine 16.

[0046] Preferably, such as Figure 1 As shown, a third three-way valve 15 is installed in LNG flow path 1, which divides LNG flow path 1 into a main path and a branch path.

[0047] The third three-way valve 15 precisely controls the ratio of LNG flow into the main line and branch lines. The system can adjust the flow distribution between the main line and branch lines by regulating the opening of the third three-way valve 15 according to actual needs, such as the refrigeration load of the cold storage and freezer compartments and the fuel requirements of the LNG engine 16. For example, when the cold storage and freezer compartments require a larger cooling capacity, the flow rate of the branch lines can be appropriately increased to allow more LNG to participate in cooling recovery; conversely, when the LNG engine 16 is operating at a high load and requires more fuel, the flow rate of the main line can be increased to ensure sufficient fuel supply to the LNG engine 16. This precise flow control enables the system to maintain optimal operating conditions under various operating conditions.

[0048] Preferably, such as Figure 1 As shown, a cold storage module 3 is also provided in the refrigeration cycle loop. The cold storage module 3 is used to store cold energy when the LNG flow path 1 is running and to release cold energy to the refrigerant when the LNG flow path 1 stops running.

[0049] When LNG flow path 1 is in operation, LNG releases cold energy in heat exchanger 13. At this time, cold storage module 3 absorbs and stores this cold energy. It acts like a "cold energy warehouse," collecting the cold energy released by LNG that is not immediately used.

[0050] When LNG flow path 1 stops operating, meaning no new cooling capacity is released from LNG, the cold storage module 3 can release the previously stored cooling capacity to the refrigerant. This ensures that the refrigerant continues to receive cooling capacity, thereby maintaining the normal operation of the cooling module and preventing the entire refrigeration cycle from being interrupted due to the cessation of LNG flow path 1.

[0051] In practical use, LNG flow path 1 may stop operating for various reasons (such as vehicle parking, short-term LNG refueling, etc.). With the cold storage module 3, when LNG flow path 1 stops operating, it can release cold energy to the refrigerant in a timely manner, ensuring that the cooling module can continue to obtain the required cold energy and maintain normal operation. There will be no shutdown of the cooling equipment due to the interruption of LNG flow path 1, which greatly improves the stability and reliability of the entire cold energy recovery system.

[0052] Furthermore, when LNG flow path 1 is running, there may be situations where the cooling demand of the cooling module is less than the cooling capacity released by LNG. In this case, the cold storage module 3 stores the excess cooling capacity, avoiding waste. When LNG flow path 1 stops running, this stored cooling capacity can be utilized effectively, allowing for more complete and efficient use of the cooling capacity released by LNG, further improving energy efficiency.

[0053] Preferably, the cold storage module 3 is a cold storage device, and the cold storage device has a groove filled with a phase change material. The phase change material is used to store and release cold energy.

[0054] Phase change materials (PCMs) can absorb or release a large amount of latent heat during phase change. Compared to methods that rely solely on the material's own temperature changes to store cold energy, PCMs can store and release a large amount of cold energy within a relatively small temperature range. This allows the accumulator to quickly and effectively store cold energy while LNG flow path 1 is running, and to stably and continuously release cold energy when LNG flow path 1 stops, greatly improving the efficiency of cold energy storage and release.

[0055] Furthermore, phase change materials maintain a relatively constant temperature during the phase change process. For example, when it changes from a solid to a liquid state, it continuously absorbs cold energy while maintaining a temperature near the phase change temperature. This characteristic allows the refrigerant accumulator to provide a relatively stable low-temperature environment for the refrigerant when releasing cold energy, thereby ensuring that the cooling module can operate under stable temperature conditions and improving the performance and product quality of the cooling equipment. For example, in refrigerated transportation, a stable low-temperature environment can better protect the quality of goods and reduce damage caused by temperature fluctuations.

[0056] Furthermore, phase change materials (PCMs) exhibit excellent chemical and thermal cycling stability, allowing for multiple phase change processes without significant performance degradation. This means that PCMs in accumulators can be used repeatedly over extended periods without frequent replacement. Compared to some disposable or short-life refrigeration storage methods, this significantly reduces system operating and maintenance costs, improving the overall economics of the vehicle-mounted LNG refrigeration recovery system.

[0057] Preferably, the refrigerant is one of ethylene glycol aqueous solution, propylene glycol aqueous solution, or calcium chloride aqueous solution.

[0058] All three refrigerant solutions have the property of lowering the freezing point, enabling them to remain liquid in low-temperature environments and ensuring that the system can operate normally under various climatic conditions and operating conditions. Whether in cold winters or in vehicles traveling in high-altitude, low-temperature areas, the refrigerant will not freeze and clog pipes or damage equipment, ensuring the stability and reliability of the vehicle-mounted LNG cold energy recovery system.

[0059] In addition, the present invention also provides a vehicle that includes the above-described vehicle-mounted LNG cold energy recovery system.

[0060] The technical solution of the present invention has been described above with reference to the preferred embodiments shown in the accompanying drawings. However, it will be readily understood by those skilled in the art that the scope of protection of the present invention is obviously not limited to these specific embodiments. Without departing from the principles of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after such changes or substitutions will all fall within the scope of protection of the present invention.

Claims

1. A vehicle-mounted LNG cold energy recovery system, characterized in that, It includes an LNG flow path (1) and a refrigeration cycle loop (2). The LNG flow path (1) is connected in sequence to an LNG storage tank (11), a first pump (12) and a heat exchanger (13). The first pump (12) is used to pump LNG from the LNG storage tank (11) and deliver it to the heat exchanger (13). The LNG can release cold energy when it flows through the heat exchanger (13). The refrigeration cycle includes a refrigerant tank (21), a second pump (22), the heat exchanger (13), and at least one cooling module connected in sequence by pipelines. The second pump (22) is used to transport the refrigerant in the refrigerant tank (21) through the heat exchanger (13) and the cooling module in sequence. The refrigerant can be cooled by the cold energy released by the LNG when it flows through the heat exchanger (13).

2. The LNG cold energy recovery system for vehicles according to claim 1, characterized in that, The refrigeration cycle loop is also equipped with a cold storage module (3), which is used to store cold energy when the LNG flow path (1) is running and to release cold energy to the refrigerant when the LNG flow path (1) stops running.

3. The LNG cold energy recovery system for vehicles according to claim 2, characterized in that, The cold storage module (3) is a cold storage device. The cold storage device has a groove, which is filled with a phase change material. The phase change material is used to store and release cold energy.

4. The LNG cooling capacity recovery system for vehicles according to claim 1, characterized in that, The cooling module includes a vehicle refrigerator, which includes a first evaporator (231) for cooling the freezer compartment and a second evaporator (232) for cooling the refrigerator compartment. A flow switching component is provided on the refrigeration cycle loop, and the flow switching component is configured to connect the first evaporator (231) and the second evaporator (232) to the refrigeration cycle loop in series or in parallel.

5. The LNG cooling capacity recovery system for vehicles according to claim 4, characterized in that, The flow path switching component includes a first three-way valve (241) and a second three-way valve (242). The inlet of the first three-way valve (241) is connected to the refrigerant outlet of the heat exchanger (13), the first outlet of the first three-way valve (241) is connected to the inlet of the first evaporator (231), and the second outlet of the first three-way valve (241) is connected to the inlet of the second evaporator (232). The inlet of the second three-way valve (242) is connected to the outlet of the first evaporator (231), the first outlet of the second three-way valve (242) is connected to the inlet of the first evaporator (231), and the second outlet of the second three-way valve (242) merges with the outlet of the second evaporator (232) and is then connected to the inlet of the refrigerant tank (21).

6. The LNG cooling capacity recovery system for vehicles according to claim 5, characterized in that, The vehicle-mounted LNG cold energy recovery system also includes a control unit and multiple temperature sensors installed in the refrigeration compartment and the freezer compartment. The first three-way valve (241) and the second three-way valve (242) are both electromagnetic three-way valves. The control unit is configured to switch the series / parallel connection mode between the first evaporator (231) and the second evaporator (232) by controlling the first three-way valve (241) and the second three-way valve (242) based on the signal from the temperature sensor, and / or The control unit is configured to adjust the opening of the first three-way valve (241) and the second three-way valve (242) in parallel mode according to the signal from the temperature sensor to distribute the refrigerant flow into the first evaporator (231) and the second evaporator (232).

7. The LNG cold energy recovery system for vehicles according to any one of claims 1 to 6, characterized in that, The coolant is one of ethylene glycol aqueous solution, propylene glycol aqueous solution, or calcium chloride aqueous solution.

8. The LNG cooling capacity recovery system for vehicles according to any one of claims 1 to 6, characterized in that, The LNG flow path (1) is split into a main path and a branch path downstream of the first pump (12). The heat exchanger (13) is located on the branch path. An LNG vaporizer (14) is located on the main path. After the LNG in the branch path flows through the heat exchanger (13), it merges with the LNG in the main path downstream of the LNG vaporizer (14) and flows together to the LNG engine (16).

9. The LNG cold energy recovery system for vehicles according to claim 8, characterized in that, The LNG flow path (1) is provided with a third three-way valve (15), which divides the LNG flow path (1) into the main path and the branch path.

10. A vehicle, characterized in that, The vehicle-mounted LNG cold energy recovery system includes any one of claims 1 to 9.

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