Vortex tube-carbon dioxide transcritical cycle heat management system for motor home and temperature-humidity-net coordinated regulation and control method of vortex tube-carbon dioxide transcritical cycle heat management system

Abstract

The invention discloses a vortex tube-carbon dioxide transcritical cycle heat management system for a motor home and a temperature-humidity-net coordinated regulation and control method of the vortex tube-carbon dioxide transcritical cycle heat management system, and belongs to the technical field of vehicle heat management. In order to solve the problems of low energy efficiency, function dispersion, insufficient air quality control and the like of an existing limo heat management system, a two-phase vortex tube and carbon dioxide transcritical cycle technology is creatively integrated, and a multi-combined-supply efficient heat management framework is constructed. According to the system, a traditional throttling valve is replaced by the two-phase vortex tube, the characteristics that the two-phase vortex tube is free of moving parts and adjustable in cold and hot flow division are utilized, the environment-friendly advantage of a carbon dioxide working medium and the efficient thermodynamic property of transcritical circulation are coupled, and cooperative operation of refrigeration, heating and heat recovery is achieved. The system comprises an air purification module, a temperature and humidity regulation and control module, a vehicle-mounted refrigerator and a hot water supply module. The system breaks through the energy efficiency bottleneck of a traditional subsystem independent framework, efficient coordinated regulation and control over the temperature, humidity and air cleanliness are achieved in a limited space, meanwhile, the requirements for food refrigeration and instant hot water supply are met, the comprehensive energy efficiency ratio is remarkably improved, and the system is suitable for limo moving life scenes in the complex environment.

Description

Technical Field

[0001] The present invention relates to the technical field of vehicle thermal management, and in particular to a vortex tube-carbon dioxide transcritical cycle thermal management system for a recreational vehicle and a temperature-humidity-net coordinated control method thereof. Background Art

[0002] In recent years, driven by rising consumption and a growing popularity of outdoor living, RV travel, with its combined functions of transportation and accommodation, has gradually expanded from a niche market into the mass consumer sector, resulting in a continued expansion of the industry. As a mobile lifestyle vehicle, RVs must integrate diverse functional modules within a limited space, including comfort control (temperature, humidity, and air cleanliness), food refrigeration, and instant hot water supply. This places core technical demands on onboard thermal management systems, including multi-scenario energy coupling and refined dynamic regulation. While RV manufacturers are attempting to enhance user experience by introducing devices such as variable-frequency air conditioners, photovoltaic energy storage systems, and intelligent control terminals, core systems such as ventilation, temperature control, humidity regulation, and hot water supply remain bottlenecked by the RV's confined space, limited energy reserves, and high adaptability to complex environments.

[0003] Current RV ventilation systems generally use either passive or active air exchange mechanisms. Both solutions suffer from systemic flaws in air quality control. Passive designs primarily rely on pre-installed ventilation louvers on the vehicle body to achieve natural ventilation. However, due to insufficient natural convection driving force in static parking scenarios, ventilation efficiency is significantly reduced, and carbon dioxide concentrations within the vehicle increase rapidly, causing hypoxia symptoms such as decreased blood oxygen saturation, drowsiness, and headaches. For this reason, the industry has turned to active ventilation solutions using external axial flow fans. While this increases the number of air changes, its core flaw is that it only replaces basic air volume without a multi-stage filtration module. This allows harmful substances such as PM2.5, pollen, and VOCs to directly enter the vehicle through the airflow. In areas with smog or industrial pollution, the negative pressure created by forced exhaust exacerbates the backflow of external pollutants, creating a binary contradiction between "air exchange volume and cleanliness." This exposes the fundamental flaw of traditional ventilation technology: it is difficult to balance aerodynamic efficiency with the ability to remove pollutants.

[0004] The cooling requirements of RV internal thermal management systems encompass two core functions: air conditioning and food preservation. Existing technical solutions face systemic technical bottlenecks that urgently need to be overcome. Regarding the energy supply system, current mainstream solutions rely on high-power cooling systems, either onboard air conditioning or via external power supplies. These systems suffer from low thermodynamic efficiency and energy conversion rates, leading to a steep drop in the discharge curve of independent battery packs during parking conditions, significantly reducing the range of the independent power supply system. Some improved solutions utilize auxiliary temperature control devices powered by internal combustion engines. While these solutions can alleviate the power load, they face limitations such as excessive combustion noise spectrum (40-65dB), challenges controlling exhaust emissions, and safety regulations for onboard fuel storage. Regarding spatial layout, the volume parameters of traditional air conditioning outdoor unit modules conflict with the compact design principles of RVs, limiting the space available for optimizing vehicle aerodynamics. Notably, existing humidity control mechanisms rely excessively on the air conditioning system. This integrated control model not only results in significant sensible heat exchange during the dehumidification / humidification process, resulting in energy quality mismatch and heat and cold cancellation, but also leads to reduced humidity control accuracy and a significant decrease in the system's energy efficiency ratio (COP) under partial load conditions. Traditional solutions lack independent humidity control modules and dynamic compensation mechanisms, making it difficult to achieve decoupled control of temperature and humidity parameters. This is particularly true in high humidity gradients or extreme environmental conditions, where condensation and hysteresis are common. This severely limits the operational stability and energy efficiency of environmental control systems. Existing solutions often use decentralized humidifiers, which take up additional space in the vehicle and increase energy consumption.

[0005] Current RV hot water supply systems primarily utilize two traditional technologies: gas heating and electric heating. Both technologies present significant technical bottlenecks in their respective applications. Gas heating devices rely on combustible gases such as propane as a heat source, requiring frequent replacement of gas tanks and posing combustion safety hazards and the risk of carbon monoxide leaks. While electric heating devices avoid the risk of open flames, they are highly sensitive to ambient temperature, experience significant energy efficiency degradation at low temperatures, and are highly dependent on a continuous external power supply. While some improved systems utilize onboard engine waste heat recovery technology to achieve thermal energy conversion, this approach has significant operating limitations. When the vehicle is in a static parked state, the waste heat recovery system completely fails, limiting its functionality in high-frequency hot water use scenarios such as camping. These technical approaches fail to meet the actual needs of modern RV users in terms of core indicators such as energy supply stability, environmental adaptability, and all-weather heating capabilities.

[0006] This patent addresses the engineering and technical challenges of integrating multiple functional requirements into a limited space in an RV. It innovatively proposes a thermodynamic system architecture based on the coupling of vortex tube refrigeration and carbon dioxide transcritical circulation. Through energy cascade utilization and multi-condition collaborative control technology, it achieves the multi-generation functions of precise control of temperature and humidity in the living environment, air purification, food refrigeration and preservation, and real-time supply of domestic hot water. This system breaks through the energy efficiency bottleneck of the dispersed layout of traditional RV equipment. Relying on the environmentally friendly characteristics of carbon dioxide working fluid and the efficient thermal characteristics of the transcritical cycle, combined with the advantages of vortex tubes, a compact heat separation device with no moving parts, it constructs a compact energy hub device. While ensuring thermal comfort indicators, it significantly improves the overall energy efficiency of the system and meets the multi-modal energy demand in mobile living scenarios. Summary of the Invention

[0007] In view of the above-mentioned deficiencies, the present invention provides a vortex tube-carbon dioxide transcritical cycle thermal management system for RVs and a temperature-humidity-net coordinated control method thereof.

[0008] The system takes into account the characteristics of the vortex tube without moving parts, compact structure, and smaller throttling loss than the expansion valve. The two-phase vortex tube replaces the throttle valve in the traditional carbon dioxide transcritical circulation system. It has both heating and cooling functions, and the temperature and flow of hot and cold air can be adjusted. The system includes a front air intake grille 1 of the RV, a fan 2, an air purifier 3, an air volume regulating valve 4, a first heat exchanger 5, a two-phase vortex tube 6, a four-way reversing valve 7, a condensate discharge pipe 8, an air supply main 9, a first flow regulating valve 10, and a second heat exchanger. 11, onboard refrigerator 12, third heat exchanger 13, first temperature sensor 14, first check valve 15, second check valve 16, compressor 17, third check valve 18, second flow regulating valve 19, third flow regulating valve 20, hot water tank 21, PCM wave shield 22, fourth flow regulating valve 23, water tank inlet pipe 24, second temperature sensor 25, water level detector 26, fifth flow regulating valve 27, fourth heat exchanger 28, safety valve 29, sixth flow regulating valve 30, and nozzle 31. By coupling a two-phase vortex tube with a transcritical carbon dioxide circulation system, an integrated and efficient thermal management solution for RVs is proposed, addressing the low overall energy efficiency of the independent subsystem architecture of traditional vehicles.

[0009] In order to achieve the above technical objectives, the present invention adopts the following technical means:

[0010] A vortex tube-carbon dioxide transcritical cycle thermal management system for a recreational vehicle and a temperature-humidity-purity coordinated control method thereof include a front intake grille of the recreational vehicle, a fan, an air purifier, an air volume regulating valve, a first heat exchanger, a two-phase vortex tube, a four-way reversing valve, a condensate discharge pipe, an air supply main, a first flow regulating valve, a second heat exchanger, an on-board refrigerator, a third heat exchanger, a first temperature sensor, a first check valve, a second check valve, a compressor, a third check valve, a second flow regulating valve, a third flow regulating valve, a hot water tank, a PCM wave-breaking plate, a fourth flow regulating valve, a water tank inlet pipe, a second temperature sensor, a water level detector, a fifth flow regulating valve, a fourth heat exchanger, a safety valve, a sixth flow regulating valve, and a nozzle.

[0011] When the outdoor temperature is high, the outdoor air introduced by the front air intake grille of the RV is connected through the inlet of the air purifier. The airflow purified by the air purifier passes through the first heat exchanger in turn for cooling and dehumidification, and is then transported through the air supply main to the second heat exchanger for reheating adjustment to form comfortable air supply and be sent into the interior of the RV. The cold gas outlet pipe of the two-phase vortex tube is connected to the inlet of the first heat exchanger, the saturated cold liquid pipe of the two-phase vortex tube is connected to the inlet of the third heat exchanger, and the superheated gas outlet pipe of the two-phase vortex tube is connected to the inlet of the second heat exchanger. The bypass branch of the second flow control valve forms a parallel topology with the first heat exchanger outlet pipe, the second heat exchanger outlet pipe and the third heat exchanger outlet pipe, and is connected to the suction end of the compressor. The exhaust end pipeline of the compressor adopts a dual-channel design: the main channel runs through the interior of the hot water tank for heat exchange, and the bypass branch is connected to the inlet of the fourth heat exchanger to form an auxiliary heat exchange channel. Finally, the outlet of the fourth heat exchanger and the hot water tank outlet pipeline are connected to the high-pressure gas inlet pipe of the two-phase vortex tube after parallel convergence, completing the construction of a complete circulation system.

[0012] When the outdoor temperature is low, the outdoor air introduced by the front air intake grille of the RV is connected to the system through the air purifier inlet. The air flow purified by the air purifier is sequentially heated through the first heat exchanger and then transported to the humidification section through the air supply main. The hot water in the hot water tank is atomized and humidified through the nozzle, mixed with the air heated by the first heat exchanger, and then enters the second heat exchanger for cooling and regulation, finally forming a comfortable air supply with appropriate temperature and humidity and introducing it into the interior of the RV. The cold gas outlet pipe of the two-phase vortex tube is connected to the inlet of the second heat exchanger, the saturated cold liquid pipe of the two-phase vortex tube is connected to the inlet of the third heat exchanger, and the superheated gas outlet pipe of the two-phase vortex tube is connected to the inlet of the first heat exchanger. The bypass branch of the second flow regulating valve forms a parallel topology with the first heat exchanger outlet pipe, the second heat exchanger outlet pipe and the third heat exchanger outlet pipe, and then is connected to the suction end of the compressor. The exhaust end pipeline of the compressor adopts a dual-channel design: the main channel runs through the interior of the hot water tank for heat exchange, and the bypass branch is connected to the inlet of the fourth heat exchanger to form an auxiliary heat exchange channel. Finally, the outlet of the fourth heat exchanger and the hot water tank outlet pipeline are connected to the high-pressure gas inlet pipe of the two-phase vortex tube after parallel convergence, completing the construction of a complete circulation system.

[0013] Furthermore, the four-way reversing valve switches the hot and cold modes according to the working conditions, and controls the communication paths between the cold gas outlet pipe and the superheated gas outlet pipe of the two-phase vortex tube and the first heat exchanger and the second heat exchanger.

[0014] Furthermore, the two-phase vortex tube is provided with the cold end orifice plate, the conical baffle and the saturated cold liquid pipe on the basis of the basic structure of the vortex tube, namely the cold gas outlet pipe, the superheated gas outlet pipe and the vortex chamber.

[0015] Furthermore, the hot water tank is provided with the PCM wave-breaking plate, the interlayer is embedded with phase change material (PCM), the interlayer edge is double-sealed (for example, hot pressing welding + silicone coating), and a certain gap is left at the bottom from the hot water tank to stabilize the water flow in the water tank and store phase change heat energy.

[0016] Furthermore, in the dual-channel design of the compressor exhaust end, the flow ratio of the main channel and the bypass branch is coordinated by the third flow regulating valve and the fifth flow regulating valve.

[0017] Furthermore, the third heat exchanger is integrated with the vehicle-mounted refrigerator, and provides cooling for the refrigerator through the saturated cold liquid pipe of the two-phase vortex tube.

[0018] Furthermore, the air purifier is linked to the air volume regulating valve to dynamically adjust the fresh air volume according to the air quality inside the RV.

[0019] Furthermore, the first temperature sensor and the second temperature sensor are used to monitor the temperatures of the vehicle refrigerator and the hot water tank in real time, and feedback is used to adjust the opening of each flow regulating valve and the frequency of the compressor.

[0020] Furthermore, the water level detector is linked to the fourth flow regulating valve to control the water replenishment operation of the water tank inlet pipe.

[0021] Furthermore, the air purifier is provided with the flow equalizer at the air inlet, the front filter adopts the gauze, the front-stage activated carbon filter element, the HEPA (High efficiency particulate air Filter) filter screen, the electrostatic dust collection device is placed in the middle, and the rear-stage activated carbon filter element is placed at the rear.

[0022] The present invention further discloses a vortex tube-carbon dioxide transcritical cycle thermal management system for RVs and a temperature-humidity-net coordinated control method thereof:

[0023] When the system is running, the front air intake grille 1 located on the windward side of the RV is opened to introduce outdoor air. When the vehicle is not in driving state or the air volume is insufficient, the fan 2 is turned on to supply air; then, the outdoor air enters the air purifier 3 through the pipe. In the air purifier 3, the outdoor air is evenly dispersed by the flow plate 36, and then passes through the gauze 37 that can filter out larger particles of dust and impurities in the outdoor air, the front-stage activated carbon filter 38 that can adsorb some toxic gases and flammable gases, and the HEPA filter 39 that can filter out particles and bacteria with a diameter greater than 0.3µm. The remaining dust in the outdoor air after filtering by the front filter is captured and adsorbed by the electrostatic dust collector 40. At the same time, the electrostatic dust collector 40 generates corona discharge to generate negative ions that are beneficial to the human body. The purified air is finally sent out of the air purifier 3 after the odor is removed by the rear-stage activated carbon filter 41.

[0024] In a hot environment, the cold gas outlet pipe 43 of the two-phase vortex tube 6 transports saturated carbon dioxide gas to the internal coil of the first heat exchanger 5, which exchanges heat with the purified outdoor air and then flows out; the superheated gas outlet pipe 44 of the two-phase vortex tube 6 transports superheated carbon dioxide gas, which is sent to the internal coil of the second heat exchanger 11 through the first flow regulating valve 10, exchanges heat with the clean air with a lower temperature and then flows out, and at the same time, is diverted through the bypass branch of the second flow regulating valve 19; the saturated cold liquid pipe 48 of the two-phase vortex tube 6 transports saturated carbon dioxide liquid to the internal coil of the third heat exchanger 13 for cooling the vehicle refrigerator 12.

[0025] Clean air passes through air volume control valve 4 and flows through first heat exchanger 5 for cooling and dehumidification. When water vapor in the air drops to the dew point, it undergoes phase change and condensation, resulting in condensed water that is discharged from condensate drain pipe 8 to the exterior of the RV. Since the air temperature after dew point treatment is generally too low, clean, dry air flows through air supply main 9 into second heat exchanger 11, where it is heated to an appropriate supply temperature before being delivered to the interior of the RV.

[0026] The saturated carbon dioxide gas after heat exchange in the first heat exchanger 5, the superheated carbon dioxide gas after heat exchange in the second heat exchanger 11, the superheated carbon dioxide gas in the bypass branch, and the saturated carbon dioxide liquid after heat exchange in the third heat exchanger 13 are mixed and sent to the compressor 17 for compression. The compressed high-temperature and high-pressure carbon dioxide gas enters the hot water tank 21 after passing through the third flow regulating valve 20, and heats the hot water stored in the hot water tank and the phase change material inside the PCM wave-breaking plate 22. The second temperature sensor 25 monitors the internal temperature of the hot water tank 21 at all times. When the temperature is too high, the third flow regulating valve 20 and the fifth flow regulating valve are adjusted. The flow regulating valve 27 allows the high-temperature and high-pressure carbon dioxide gas to enter the fourth heat exchanger 28 placed in the middle area of the bottom of the RV through the bypass branch for heat dissipation; a water level detector 26 is provided inside the hot water tank 21. When the water volume is insufficient, the fourth flow regulating valve 23 is opened to draw water from the RV's clean water tank through the water tank inlet pipe 23; the carbon dioxide gas cooled by the fourth heat exchanger 28 is mixed with the carbon dioxide gas after heat exchange in the hot water tank 21, and after passing through the safety valve 29 that can play the role of overpressure protection and emergency pressure relief, it enters the high-pressure gas inlet pipe 42 of the two-phase vortex tube 6 for expansion, completing a flow tube-carbon dioxide transcritical cycle.

[0027] In a cold environment, the superheated gas outlet pipe 44 of the two-phase vortex tube 6 transports superheated carbon dioxide gas to the internal coil of the first heat exchanger 5, which exchanges heat with the purified outdoor air and then flows out; the cold gas outlet pipe 43 of the two-phase vortex tube 6 transports saturated carbon dioxide gas through the first flow regulating valve 10 to the internal coil of the second heat exchanger 11, exchanges heat with the clean air with a higher temperature and then flows out, and at the same time realizes diversion through the bypass branch of the second flow regulating valve 19; the saturated cold liquid pipe 48 of the two-phase vortex tube 6 transports saturated carbon dioxide liquid to the internal coil of the third heat exchanger 13 for refrigeration of the vehicle refrigerator 12.

[0028] The clean air passes through the first heat exchanger 5 through the air volume regulating valve 4 for temperature treatment, and is then transported to the humidification section through the air supply main 9; the hot water in the hot water tank 21 is atomized and humidified through the nozzle 31, mixed with the air heated by the first heat exchanger 5, and then enters the second heat exchanger 11 for temperature reduction and adjustment, finally forming comfortable air supply with appropriate temperature and humidity and sending it into the RV.

[0029] The superheated carbon dioxide gas after heat exchange in the first heat exchanger 5, the saturated carbon dioxide gas after heat exchange in the second heat exchanger 11, the saturated carbon dioxide gas in the bypass branch, and the saturated carbon dioxide liquid after heat exchange in the third heat exchanger 13 are mixed and sent to the compressor 17 for compression. The compressed high-temperature and high-pressure carbon dioxide gas enters the hot water tank 21 after passing through the third flow regulating valve 20, and heats the hot water stored in the hot water tank and the phase change material inside the PCM wave-breaking plate 22. The second temperature sensor 25 monitors the internal temperature of the hot water tank 21 at all times. When the temperature is too high, the third flow regulating valve 20 and the fifth flow regulating valve are adjusted. The flow regulating valve 27 allows the high-temperature and high-pressure carbon dioxide gas to enter the fourth heat exchanger 28 placed in the middle area of the bottom of the RV through the bypass branch for heat dissipation; a water level detector 26 is provided inside the hot water tank 21. When the water volume is insufficient, the fourth flow regulating valve 23 is opened to draw water from the RV's clean water tank through the water tank inlet pipe 23; the carbon dioxide gas cooled by the fourth heat exchanger 28 is mixed with the carbon dioxide gas after heat exchange in the hot water tank 21, and after passing through the safety valve 29 that can play the role of overpressure protection and emergency pressure relief, it enters the high-pressure gas inlet pipe 42 of the two-phase vortex tube 6 for expansion, completing a flow tube-carbon dioxide transcritical cycle.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] 1. This invention utilizes a vortex tube-CO2 transcritical cycle thermal management system for RVs and its coordinated temperature-humidity-purity control method. This system integrates a two-phase vortex tube with a CO2 transcritical cycle system to achieve unified control of onboard refrigerator refrigeration, in-vehicle air conditioning, and domestic hot water supply, thereby improving the overall energy efficiency of the vehicle.

[0032] 2. The present invention employs a vortex tube-CO2 transcritical cycle thermal management system for RVs and its coordinated temperature-humidity-net control method. This system uses a two-phase vortex tube to replace the conventional throttle valve, a throttling and pressure-reducing element. This simple structure reduces throttling losses, thereby improving the performance of the transcritical cycle system.

[0033] 3. This invention utilizes a vortex tube-CO2 transcritical cycle thermal management system for RVs and its coordinated temperature-humidity-net control method. Heat from the high-temperature CO2 working fluid at the compressor outlet is recovered through a hot water tank and combined with PCM phase change material heat storage to effectively reduce the energy consumption for domestic hot water heating.

[0034] 4. This invention utilizes a vortex tube-CO2 transcritical cycle thermal management system for RVs and its coordinated temperature-humidity-purity control method. The hot water tank features a built-in PCM wave shield and double sealing (hot-press welding + silicone coating) to effectively prevent leakage caused by vehicle vibrations, effectively extending its service life.

[0035] 5. This invention utilizes a vortex tube-CO2 transcritical cycle thermal management system for RVs and its coordinated temperature-humidity-purity control method. The air purifier incorporates a built-in multi-layer filter (gauze + activated carbon + HEPA + electrostatic dust collector), achieving a PM2.5 filtration efficiency of ≥ 99% while removing harmful gases, ensuring in-vehicle air quality meets ISO 14644 cleanliness standards.

[0036] 6. This invention utilizes a vortex tube-CO2 transcritical cycle thermal management system for RVs and its coordinated temperature-humidity-purity control method. By linking a flow control valve with a temperature sensor, the system can independently regulate the cold / hot airflow ratio and hot water temperature, achieving a temperature control accuracy of ±0.5°C.

[0037] 7. The present invention adopts a vortex tube-carbon dioxide transcritical cycle thermal management system for RVs and its temperature-humidity-net coordinated control method. The two-phase vortex tube design has no moving parts, reducing the failure rate and enhancing system reliability.

[0038] 8. This invention utilizes a vortex tube-CO2 transcritical cycle thermal management system for RVs and its coordinated temperature-humidity-net control method. A hot water tank and a gas cooler are connected in parallel at the compressor outlet. When the hot water tank is full and the PCM phase change material completes phase change heat storage, heat dissipation automatically switches to the gas cooler, preventing ineffective discharge of high-temperature working fluid. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 This is a working principle diagram of a vortex tube-carbon dioxide transcritical cycle thermal management system for RVs and its temperature-humidity-net coordinated control method.

[0040] Figure 2 This is a schematic diagram of the seasonal working mode principle of the four-way reversing valve used in the vortex tube-carbon dioxide transcritical cycle thermal management system for RVs and the temperature-humidity-net coordinated control method thereof of the present invention.

[0041] Figure 3 This is a simplified planar structural diagram of an air purifier used in a vortex tube-carbon dioxide transcritical cycle thermal management system for a recreational vehicle and a temperature-humidity-purity coordinated control method thereof according to the present invention.

[0042] Figure 4 This is a cross-sectional view of the overall structure of a two-phase vortex tube used in a vortex tube-carbon dioxide transcritical cycle thermal management system for a recreational vehicle and a temperature-humidity-net coordinated control method thereof according to the present invention.

[0043] Figure 5 for Figure 4 Schematic cross-sectional view of the structure at line AA.

[0044] Reference numerals in the accompanying drawings:

[0045] 1. Front air intake grille, 2. Fan, 3. Air purifier, 4. Air volume control valve, 5. First heat exchanger, 6. Two-phase vortex tube, 7. Four-way reversing valve, 8. Condensate discharge pipe, 9. Air supply main, 10. First flow control valve, 11. Second heat exchanger, 12. Car refrigerator, 13. Third heat exchanger, 14. First temperature sensor, 15. First check valve, 16. Second check valve, 17. Compressor, 18. Third check valve, 19. Second flow control valve, 20. Third flow control valve, 2 1. Hot water tank, 22. PCM wave shield, 23. Fourth flow control valve, 24. Water tank inlet pipe, 25. Second temperature sensor, 26. Water level detector, 27. Fifth flow control valve, 28. Fourth heat exchanger, 29. Safety valve, 30. Sixth flow control valve, 31. Nozzle, 32. Pipeline 1, 33. Pipeline 2, 34. Pipeline 3, 35. Pipeline 4, 36. Flow equalizer, 37. Gauze, 38. Pre-stage activated carbon filter, 39. HEPA (High Efficiency Partial Emission Control) 40. Electrostatic dust collector, 41. Post-stage activated carbon filter, 42. High-pressure gas inlet pipe, 43. Cold gas outlet pipe, 44. Superheated gas outlet pipe, 45. Saturated cold liquid pipe, 46. Cold-end orifice plate, 47. Vortex chamber, 48. Conical baffle, 49. Hot-end valve, 50. Metal casing, 51. Nozzle 1, 52. Nozzle 2, 53. Nozzle 3. DETAILED DESCRIPTION

[0046] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the specific embodiments of the present invention are described in further detail below in conjunction with the accompanying drawings. The following embodiments or drawings are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0047] 1. Device connection method

[0048] When the outdoor temperature is high, the outdoor air introduced by the RV air conditioning system through the front air intake grille 1 is processed by the air purifier 3 and then flows through the first heat exchanger 5 and the air supply main 9 in sequence. Finally, it is reheated and conditioned by the second heat exchanger 11 before being delivered into the vehicle. The two-phase vortex tube cold gas outlet pipe 43 is connected to the first heat exchanger 5 through pipe 1 32 in the four-way reversing valve 7. The vortex tube superheated gas outlet pipe 44 is connected to the second heat exchanger 11 through pipe 2 33 in the four-way reversing valve 7. The vortex tube saturated cold liquid pipe 45 is connected to the inlet of the third heat exchanger 13. The bypass branch of the second flow control valve 19 forms a parallel topology with the outlet pipes of the first heat exchanger 5, the second heat exchanger 11, and the third heat exchanger 13, and then is connected to the intake end of the compressor 17. The exhaust end of the compressor 17 adopts a dual-channel design: the main channel runs through the hot water tank 21 for heat exchange, and the bypass branch is connected to the inlet of the fourth heat exchanger 28. The two channels finally converge and connect to the vortex tube high-pressure gas inlet pipe 42 to form a complete cycle.

[0049] When the outdoor temperature is low, the outdoor air introduced by the RV air conditioning system through the front air intake grille 1 is processed by the air purifier 3, flows through the first heat exchanger 5 and the air supply main 9, and then flows through the hot water in the hot water tank 21 through the nozzle 31 for atomization and humidification. Finally, it is cooled and regulated by the second heat exchanger 11 before being delivered into the vehicle. The two-phase vortex tube cold gas outlet pipe 43 is connected to the second heat exchanger 11 through the pipe 4 35 in the four-way reversing valve 7. The vortex tube superheated gas outlet pipe 44 is connected to the first heat exchanger 5 through the pipe 3 34 in the four-way reversing valve 7. The vortex tube saturated cold liquid pipe 45 is connected to the inlet of the third heat exchanger 13. The bypass branch of the second flow control valve 19 forms a parallel topology with the outlet pipes of the first heat exchanger 5, the second heat exchanger 11, and the third heat exchanger 13, and then is connected to the intake end of the compressor 17. The exhaust end of the compressor 17 adopts a dual-channel design: the main channel runs through the hot water tank 21 for heat exchange, and the bypass branch is connected to the inlet of the fourth heat exchanger 28. The two channels finally converge and connect to the vortex tube high-pressure gas inlet pipe 42 to form a complete cycle.

[0050] 2. Operating principle of two-phase vortex tube

[0051] When the two-phase vortex tube 6 begins operation, the supercritical pressure carbon dioxide gas entering from supersonic nozzle 1 51, nozzle 2 52, and nozzle 3 53 is accelerated to the speed of sound and then sent into the vortex chamber 47 for high-speed rotation. The carbon dioxide gas is divided into two layers, the inner and outer layers. The temperature of the outer layer of carbon dioxide gas gradually increases and is discharged from the superheated gas outlet pipe 44 at the hot end through the hot end valve 49. The carbon dioxide gas in the inner layer gradually cools down and is blocked by the hot end valve 49 before flowing to the cold end and out through the cold gas outlet pipe 43. The hot end valve 49 can be used to adjust the ratio of hot and cold flow rates to achieve the optimal cooling or heating effect. The periodic oscillation of the shock wave train of supercritical pressure carbon dioxide gas in supersonic nozzle 1 51, nozzle 2 52, and nozzle 3 53 causes a sudden drop in local pressure, causing the carbon dioxide working medium to cross the gas-liquid equilibrium line and enter the metastable region, thereby condensing to form droplets. The condensed carbon dioxide is then discharged from the saturated cold liquid pipe 45.

[0052] 3. Phase change material of PCM wave shield

[0053] The phase-change energy storage material of the present invention is preferably a paraffin compound. This material exhibits significant solid-liquid phase transition properties within the temperature range required by RV hot water systems (40-60°C), with n-tricosane being particularly outstanding due to its phase transition point of 46°C. Thermodynamic parameters of this material reveal a latent heat of phase change of 180-230 kJ / kg, a liquid specific heat capacity of 2.27 J / (g·K), and a solid specific heat capacity of 2.1 J / (g·K). This high heat capacity provides excellent thermal energy storage capabilities. Of particular note, the 46°C phase transition temperature ideally matches the operating temperature of hot water in RV domestic hot water systems (including kitchen washing and bathing applications), effectively storing waste heat energy while ensuring a comfortable hot water output temperature.

[0054] 4. System operation mode

[0055] When the system is running, the front air intake grille 1 located on the windward side of the RV is opened to introduce hot and humid outdoor air. When the vehicle is not in driving state or the air volume is insufficient, the fan 2 is turned on to supply air; then, the outdoor air enters the air purifier 3 through the pipe. In the air purifier 3, the outdoor air is evenly dispersed by the flow plate 36, and then passes through the gauze 37 that can filter out larger particles of dust and impurities in the outdoor air, the front-stage activated carbon filter 38 that can adsorb some toxic gases and flammable gases, and the HEPA filter 39 that can filter out particles and bacteria with a diameter greater than 0.3µm. The remaining dust in the outdoor air after filtering by the front filter is captured and adsorbed by the electrostatic dust collector 40. At the same time, the electrostatic dust collector 40 generates corona discharge to generate negative ions that are beneficial to the human body. The purified air is finally sent out of the air purifier 3 after the odor is removed by the rear-stage activated carbon filter 41.

[0056] When the outdoor temperature is high, the cold gas outlet pipe 43 of the two-phase vortex tube 6 transports saturated carbon dioxide gas through the pipe 1 32 of the four-way reversing valve 7 to be connected to the internal coil of the first heat exchanger 5, and flows out after heat exchange with the purified outdoor air; the superheated gas outlet pipe 44 of the two-phase vortex tube 6 transports superheated carbon dioxide gas through the pipe 2 33 of the four-way reversing valve 7, and is sent to the internal coil of the second heat exchanger 11 through the first flow regulating valve 10, and flows out after heat exchange with the clean air with a lower temperature, and at the same time, is diverted through the bypass branch of the second flow regulating valve 19; the saturated cold liquid pipe 48 of the two-phase vortex tube 6 transports saturated carbon dioxide liquid to the internal coil of the third heat exchanger 13 for cooling the vehicle refrigerator 12.

[0057] Clean air passes through air volume control valve 4 and flows through first heat exchanger 5 for cooling and dehumidification. When water vapor in the air drops to the dew point, it undergoes phase change and condensation, resulting in condensed water that is discharged from condensate drain pipe 8 to the exterior of the RV. Since the air temperature after dew point treatment is generally too low, clean, dry air flows through air supply main 9 into second heat exchanger 11, where it is heated to an appropriate supply temperature before being delivered to the interior of the RV.

[0058] The saturated carbon dioxide gas after heat exchange in the first heat exchanger 5, the superheated carbon dioxide gas after heat exchange in the second heat exchanger 11, the superheated carbon dioxide gas in the bypass branch, and the saturated carbon dioxide liquid after heat exchange in the third heat exchanger 13 are mixed and sent to the compressor 17 for compression. The compressed high-temperature and high-pressure carbon dioxide gas enters the hot water tank 21 after passing through the third flow regulating valve 20, and heats the hot water stored in the hot water tank and the phase change material inside the PCM wave-breaking plate 22. The second temperature sensor 25 monitors the internal temperature of the hot water tank 21 at all times. When the temperature is too high, the third flow regulating valve 20 and the fifth flow regulating valve are adjusted. The flow regulating valve 27 allows the high-temperature and high-pressure carbon dioxide gas to enter the fourth heat exchanger 28 placed in the middle area of the bottom of the RV through the bypass branch for heat dissipation; a water level detector 26 is provided inside the hot water tank 21. When the water volume is insufficient, the fourth flow regulating valve 23 is opened to draw water from the RV's clean water tank through the water tank inlet pipe 23; the carbon dioxide gas cooled by the fourth heat exchanger 28 is mixed with the carbon dioxide gas after heat exchange in the hot water tank 21, and after passing through the safety valve 29 that can play the role of overpressure protection and emergency pressure relief, it enters the high-pressure gas inlet pipe 42 of the two-phase vortex tube 6 for expansion, completing a flow tube-carbon dioxide transcritical cycle.

[0059] When the outdoor temperature is low, the superheated gas outlet pipe 44 of the two-phase vortex tube 6 transports the superheated carbon dioxide gas to the internal coil of the first heat exchanger 5 through the pipe three 34 of the four-way reversing valve 7, and flows out after exchanging heat with the purified outdoor air; the cold gas outlet pipe 43 of the two-phase vortex tube 6 transports the saturated carbon dioxide gas through the pipe four 35 of the four-way reversing valve 7 through the first flow regulating valve 10 to the internal coil of the second heat exchanger 11, exchanges heat with the clean air with a higher temperature and flows out, and at the same time realizes diversion through the bypass branch of the second flow regulating valve 19; the saturated cold liquid pipe 48 of the two-phase vortex tube 6 transports the saturated carbon dioxide liquid to the internal coil of the third heat exchanger 13 for refrigeration of the vehicle refrigerator 12.

[0060] The clean air passes through the first heat exchanger 5 through the air volume regulating valve 4 for temperature treatment, and is then transported to the humidification section through the air supply main 9; the hot water in the hot water tank 21 is atomized and humidified through the nozzle 31, mixed with the air heated by the first heat exchanger 5, and then enters the second heat exchanger 11 for temperature reduction and adjustment, finally forming comfortable air supply with appropriate temperature and humidity and sending it into the RV.

[0061] The superheated carbon dioxide gas after heat exchange in the first heat exchanger 5, the saturated carbon dioxide gas after heat exchange in the second heat exchanger 11, the saturated carbon dioxide gas in the bypass branch, and the saturated carbon dioxide liquid after heat exchange in the third heat exchanger 13 are mixed and sent to the compressor 17 for compression. The compressed high-temperature and high-pressure carbon dioxide gas enters the hot water tank 21 after passing through the third flow regulating valve 20, and heats the hot water stored in the hot water tank and the phase change material inside the PCM wave-breaking plate 22. The second temperature sensor 25 monitors the internal temperature of the hot water tank 21 at all times. When the temperature is too high, the third flow regulating valve 20 and the fifth flow regulating valve are adjusted. The flow regulating valve 27 allows the high-temperature and high-pressure carbon dioxide gas to enter the fourth heat exchanger 28 placed in the middle area of the bottom of the RV through the bypass branch for heat dissipation; a water level detector 26 is provided inside the hot water tank 21. When the water volume is insufficient, the fourth flow regulating valve 23 is opened to draw water from the RV's clean water tank through the water tank inlet pipe 23; the carbon dioxide gas cooled by the fourth heat exchanger 28 is mixed with the carbon dioxide gas after heat exchange in the hot water tank 21, and after passing through the safety valve 29 that can play the role of overpressure protection and emergency pressure relief, it enters the high-pressure gas inlet pipe 42 of the two-phase vortex tube 6 for expansion, completing a flow tube-carbon dioxide transcritical cycle.

[0062] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A vortex tube-carbon dioxide transcritical cycle thermal management system for RVs and a temperature-humidity-net coordinated control method thereof, characterized by: The RV comprises a front air intake grille (1), a fan (2), an air purifier (3), an air volume regulating valve (4), a first heat exchanger (5), a two-phase vortex tube (6), a four-way reversing valve (7), a condensed water discharge pipe (8), an air supply main pipe (9), a first flow regulating valve (10), a second heat exchanger (11), an onboard refrigerator (12), a third heat exchanger (13), a first temperature sensor (14), a first one-way valve (15), a second one-way valve (16), a compressor (17), a third one-way valve (18), a second flow regulating valve (19), a third flow regulating valve (20), a hot water tank (21), a PCM wave-breaking plate (22), a fourth flow regulating valve (23), a water tank water inlet pipe (24), a second temperature sensor (25), a water level detector (26), a fifth flow regulating valve (27), a fourth heat exchanger (28), a safety valve (29), a sixth flow regulating valve (30), and a nozzle (31). When the outdoor temperature is high, the outdoor air introduced by the front air intake grille (1) of the RV is connected to the inlet of the air purifier (3). The air flow purified by the air purifier (3) is sequentially passed through the first heat exchanger (5) for cooling and dehumidification, and then transported to the second heat exchanger (11) through the air supply main (9) for reheating adjustment to form a comfortable air supply temperature before being sent to the interior of the RV. The cold gas outlet pipe of the two-phase vortex tube (6) is connected to the inlet of the first heat exchanger (5), the saturated cold liquid pipe of the two-phase vortex tube (6) is connected to the inlet of the third heat exchanger (13), and the superheated gas outlet pipe of the two-phase vortex tube (6) is connected to the inlet of the second heat exchanger (11). The bypass branch of the second flow regulating valve (19) forms a parallel topological structure with the outlet pipe of the first heat exchanger (5), the outlet pipe of the second heat exchanger (11) and the outlet pipe of the third heat exchanger (13), and then is connected to the suction end of the compressor (17). The exhaust pipe of the compressor (17) adopts a dual-channel design: the main channel runs through the interior of the hot water tank (21) for heat exchange, and the bypass branch is connected to the inlet of the fourth heat exchanger (28) to form an auxiliary heat exchange channel. Finally, the outlet of the fourth heat exchanger (28) and the outlet pipe of the hot water tank (21) are connected in parallel and then connected to the high-pressure gas inlet pipe of the two-phase vortex tube (6), completing the construction of a complete circulation system. When the outdoor temperature is low, the outdoor air introduced by the front air intake grille (1) of the RV is connected to the system through the inlet of the air purifier (3). The air flow purified by the air purifier (3) passes through the first heat exchanger (5) in turn for temperature treatment, and is then transported to the humidification section through the air supply main pipe (9); the hot water in the hot water tank (21) is atomized and humidified through the nozzle (31), mixed with the air heated by the first heat exchanger (5), and then enters the second heat exchanger (11) for temperature reduction regulation, finally forming clean and comfortable air supply with appropriate temperature and humidity and introducing it into the interior of the RV.The cold gas outlet pipe of the two-phase vortex tube (6) is connected to the inlet of the second heat exchanger (11), the saturated cold liquid pipe of the two-phase vortex tube (6) is connected to the inlet of the third heat exchanger (13), and the superheated gas outlet pipe of the two-phase vortex tube (6) is connected to the inlet of the first heat exchanger (5). The bypass branch of the second flow regulating valve (19) forms a parallel topological structure with the outlet pipe of the first heat exchanger (5), the outlet pipe of the second heat exchanger (11) and the outlet pipe of the third heat exchanger (13), and then is connected to the suction end of the compressor (17). The exhaust end pipeline of the compressor (17) adopts a dual-channel design: the main channel runs through the interior of the hot water tank (21) for heat exchange, and the bypass branch is connected to the inlet of the fourth heat exchanger (28) to form an auxiliary heat exchange channel. Finally, the outlet of the fourth heat exchanger (28) and the outlet pipeline of the hot water tank (21) are connected in parallel and then connected to the high-pressure gas inlet pipe of the two-phase vortex tube (6), completing the construction of a complete circulation system.

2. A vortex tube-carbon dioxide transcritical cycle thermal management system for a recreational vehicle and a temperature-humidity-net coordinated control method thereof according to claim 1, characterized in that: The four-way reversing valve (7) switches between the cold and hot modes according to the working conditions, and controls the communication paths between the cold gas outlet pipe and the superheated gas outlet pipe of the two-phase vortex tube (6) and the first heat exchanger (5) and the second heat exchanger (11).

3. A vortex tube-carbon dioxide transcritical cycle thermal management system for a recreational vehicle and a temperature-humidity-net coordinated control method thereof according to claim 1, characterized in that: The two-phase vortex tube (6) is provided with the cold end orifice plate (46), the conical baffle (48) and the saturated cold liquid pipe (45) on the basis of the basic structure of the vortex tube, namely the cold gas outlet pipe (43), the superheated gas outlet pipe (44) and the vortex chamber (47).

4. A vortex tube-carbon dioxide transcritical cycle thermal management system for a recreational vehicle and a temperature-humidity-net coordinated control method thereof according to claim 1, characterized in that: The PCM anti-wave plate (22) is provided in the hot water tank (21), a phase change material (PCM) is embedded in the interlayer, the edge of the interlayer is double-sealed (e.g., hot pressing welding + silicone coating), and a certain gap is left at the bottom from the hot water tank to stabilize the water flow in the water tank and store phase change heat energy.

5. The vortex tube-carbon dioxide transcritical cycle thermal management system for RVs and the temperature-humidity-net coordinated control method thereof according to claim 1, characterized in that: In the dual-channel design of the exhaust end of the compressor (17), the flow ratio of the main channel and the bypass branch is coordinated by the third flow regulating valve (20) and the fifth flow regulating valve (27).

6. A vortex tube-carbon dioxide transcritical cycle thermal management system for a recreational vehicle and a temperature-humidity-net coordinated control method thereof according to claim 1, characterized in that: The third heat exchanger (13) is integrated with the vehicle-mounted refrigerator (12) and provides cooling capacity for the refrigerator through the saturated cold liquid pipe of the two-phase vortex tube (6).

7. The vortex tube-carbon dioxide transcritical cycle thermal management system for a recreational vehicle and the temperature-humidity-net coordinated control method thereof according to claim 1, characterized in that: The air purifier (3) is linked to the air volume regulating valve (4) to dynamically adjust the fresh air volume according to the air quality inside the RV.

8. The vortex tube-carbon dioxide transcritical cycle thermal management system for a recreational vehicle and the temperature-humidity-net coordinated control method thereof according to claim 1, characterized in that: The first temperature sensor (14) and the second temperature sensor (25) monitor the temperature of the vehicle refrigerator (12) and the hot water tank (21) in real time, and feedback adjusts the opening of each flow regulating valve and the frequency of the compressor.

9. The vortex tube-carbon dioxide transcritical cycle thermal management system for RVs and the temperature-humidity-net coordinated control method thereof according to claim 1, characterized in that: The water level detector (26) is linked to the fourth flow regulating valve (23) to control the water replenishment operation of the water tank inlet pipe (24).

10. The vortex tube-carbon dioxide transcritical cycle thermal management system for a recreational vehicle and the temperature-humidity-net coordinated control method thereof according to claim 1, characterized in that: The air inlet of the air purifier (3) is provided with the flow equalizer (29), the front filter screen adopts the gauze screen (30), the front stage activated carbon filter element (31), the HEPA (High Efficiency Particulate Air Filter) filter screen (32), the electrostatic dust collection device (33) is arranged in the middle, and the rear stage activated carbon filter element (34) is arranged at the rear.

Images