Supercritical CO2 dry airtight closed thermal management system based on vortex tube

Abstract

The invention relates to the field of supercritical CO2 Brayton cycle, and provides a supercritical CO2 dry airtight closed heat management system based on a vortex tube, which is characterized in that a vortex chamber is communicated with a compressor working medium outlet through a vortex tube air inlet pipeline, and high-temperature hot air flowing out of a hot end pipe enters a compressor end sealing cavity through a vortex tube hot end air outlet pipeline; the compressor end sealing cavity is communicated with the compressor medium outlet through the compressor end sealing cavity air outlet gap, so that a working medium in the compressor end sealing cavity flows back to the vortex tube air inlet pipeline; the vortex tube cold end air outlet pipeline is communicated with the cooling cavity air inlet, so that low-temperature cold air flowing out of the cold end tube enters the cooling cavity; and the cooling cavity air outlet is communicated with the compressor medium outlet, so that the working medium in the cooling cavity flows back to the vortex tube air inlet pipeline. The method is of great significance to high-efficiency, low-leakage and stable operation of the supercritical CO2 Brayton cycle power generation turbine unit.

Description

Technical Field

[0001] The present invention relates to the field of supercritical carbon dioxide Brayton cycle, and in particular to a supercritical CO2 Brayton cycle based on a vortex tube. 2 Dry gas sealed closed thermal management system. Background Art

[0002] Supercritical CO 2 The Brayton cycle power generation system is a Brayton cycle system that uses supercritical carbon dioxide as the working fluid. Its cycle process is: first, the supercritical carbon dioxide is pressurized by a compressor; then, the working fluid is heated at isobaric pressure using a heat exchanger; secondly, the working fluid enters the turbine, drives the turbine to do work, and the turbine drives the motor to generate electricity; finally, the working fluid enters the cooler, returns to its initial state, and then enters the compressor to form a closed cycle.

[0003] Supercritical CO 2 The Brayton cycle power generation system is one of the most promising energy conversion systems in the future. In order to ensure the competitiveness of the energy conversion system, the high efficiency and low leakage operation of the compressor and high temperature turbine (turbine), which are the core equipment of the system, are crucial. Non-contact dry gas seals have become the main form of shaft end seals for compressors and high temperature turbines because of their excellent leakage control capabilities under high parameter conditions.

[0004] When supercritical CO 2 When the turbine is running, the supercritical CO drawn from the compressor diffuser outlet 2 After filtering, heating and pressure regulation, the medium is introduced into the compressor end sealing chamber as the medium gas for the compressor end dry gas seal. At the same time, part of the gas is led back to the compressor diffuser through the compressor wheel back gap (compressor end sealing chamber outlet gap). Since the gas led out of the compressor diffuser outlet needs to pass through various flow resistance elements before entering the compressor end sealing chamber, causing a significant temperature drop, if there is no heating measure, it will cause a lower temperature when entering the compressor end sealing chamber. At a lower intake temperature, supercritical CO 2 The dry gas seal at the compressor end may undergo phase change during operation, and liquid or even solid CO may appear on the seal end surface. 2 , which will destroy the stability of the gas film and increase the risk of leakage, while solid dry ice will directly cause friction and wear on the sealing end face, causing the seal to fail prematurely. 2 The unfavorable phase transition of liquid or solid phase at the sealing end face is the key to ensure the supercritical CO 2The dry gas seal at the compressor end is one of the key factors for stable operation, and increasing the intake air temperature in the compressor end seal cavity is an effective means to control this unfavorable phase change. The current method to deal with this problem is to add a heating device to the intake air pipeline of the compressor end seal cavity to increase the intake air temperature. On the one hand, this temperature control method will make the auxiliary system very complicated and occupy a large space, resulting in its application being limited in some space-constrained occasions. On the other hand, since the heating device is an energy-consuming component, this will reduce the overall operating economy of the unit. For supercritical CO 2 The dry gas seal at the high-temperature turbine end has a high temperature in the sealing cavity at the turbine end (up to 500°C). At this temperature, the sealing end face will experience large thermal deformation. At the same time, under high temperature conditions, supercritical CO 2 The corrosion of sealing parts is relatively serious. At present, the general measure is to add insulation devices or cooling systems to reduce the medium temperature in the sealing chamber of the turbine end. However, the use of insulation devices will increase the overall axial size of the turbine unit, and the external cooling system also needs to be supplemented with energy-consuming components such as heat exchangers, thereby reducing the unit's operating economy and increasing its structural complexity. Summary of the invention

[0005] In order to solve the above problems, the present invention provides a supercritical CO 2 The dry gas sealed closed thermal management system has an ingenious design and good economy. This application realizes supercritical CO by setting up a vortex tube. 2 The hot and cold fluids of the high-pressure gas drawn out of the compressor are separated, so that the hot fluid is used as the sealing gas of the dry gas seal at the compressor end to avoid liquid condensation on the sealing end face, and the cold fluid is used to cool the high-temperature turbine end sealing cavity to avoid large thermal deformation of the sealing end face and serious corrosion of the sealing components. The present application does not need to set up energy-consuming components such as the medium gas heating device and the cooling system of the turbine end dry gas sealing pair, nor does it need to set up a heat insulation device, which reduces the space occupation and greatly improves the overall operation economy of the unit, which is very important for supercritical CO 2 The high efficiency, low leakage and stable operation of the Brayton cycle power generation turbine unit is of great significance. The technical solution adopted in this application is as follows:

[0006] A supercritical CO dry gas sealed closed thermal management system based on a vortex tube, comprising:

[0007] The compressor end seal assembly includes a compressor end seal cavity, a compressor end dry gas seal pair and a compressor end seal cavity outlet gap, wherein the compressor end seal cavity is arranged around the outer periphery of the compressor end dry gas seal pair, and the compressor end seal cavity outlet gap is connected with the compressor end seal cavity. The turbine end seal assembly includes a turbine end seal cavity, a turbine end dry gas seal pair and a cooling cavity, wherein the turbine end seal cavity is arranged around the outer periphery of the turbine end dry gas seal pair, and the cooling cavity is arranged at the outer periphery of the turbine end seal cavity, and the cooling cavity is provided with a cooling cavity air inlet hole and a cooling cavity air outlet hole. The vortex tube includes a vortex chamber, a hot end tube and a cold end tube, wherein the hot end tube and the cold end tube are respectively connected to the two sides of the vortex chamber; the medium temperature and pressure measurement and control system includes a vortex tube air inlet pipeline, a vortex tube hot end air outlet pipeline and a vortex tube cold end air outlet pipeline.

[0008] The vortex chamber is connected to the compressor diffuser outlet through the vortex tube inlet pipeline, and the hot gas with a higher temperature flowing out of the hot end tube enters the compressor end sealed cavity through the vortex tube hot end outlet pipeline; the compressor end sealed cavity is connected to the compressor diffuser through the compressor end sealed cavity outlet gap, so that the working medium in the compressor end sealed cavity flows back to the vortex tube inlet pipeline. The vortex tube cold end outlet pipeline is connected to the cooling cavity inlet hole, so that the cold air with a lower temperature flowing out of the cold end tube enters the cooling cavity; the cooling cavity outlet hole is connected to the compressor diffuser, so that the working medium in the cooling cavity flows back to the vortex tube inlet pipeline.

[0009] In some embodiments, the compressor end sealing assembly also includes a compressor end sealing cavity, a compressor end dynamic ring assembly, and a compressor end static ring assembly. The compressor end sealing cavity is arranged in the compressor end sealing cavity. The compressor end dynamic ring assembly includes a compressor end dynamic ring. The compressor end static ring assembly includes a compressor end static ring. The compressor end dynamic ring and the compressor end static ring constitute the compressor end dry gas sealing pair.

[0010] In some embodiments, the turbine end sealing assembly also includes a turbine end sealing cavity, a turbine end dynamic ring assembly and a turbine end static ring assembly, the turbine end sealing cavity is arranged in the turbine end sealing cavity, the cooling cavity is opened on the turbine end sealing cavity, the turbine end dynamic ring assembly includes a turbine end dynamic ring, the turbine end static ring assembly includes a turbine end static ring, and the turbine end dynamic ring and the turbine end static ring constitute the turbine end dry gas sealing pair.

[0011] In some embodiments, the compressor end sealing assembly also includes a compressor wheel back pressure cover, which is arranged between the compressor end sealing cavity and the impeller of the compressor, and an air outlet gap of the compressor end sealing cavity is formed between the compressor wheel back pressure cover and the impeller.

[0012] In some embodiments, a baffle is provided in the cooling chamber.

[0013] In some embodiments, a first pressure regulating valve, a first temperature sensor and a first pressure sensor are provided on the vortex tube inlet pipe, a second pressure regulating valve, a second temperature sensor and a second pressure sensor are provided on the hot end outlet pipe of the vortex tube, a third temperature sensor is provided on the cold end outlet pipe of the vortex tube, and a fourth temperature sensor and a third pressure sensor are provided on the connecting path between the cooling chamber outlet hole and the compressor diffuser.

[0014] The present application provides a supercritical CO based on a vortex tube. 2 The dry gas sealed closed thermal management system has at least one of the following beneficial effects:

[0015] 1. A supercritical CO2 reactor based on a vortex tube provided in this application 2 The dry gas sealed closed thermal management system realizes the thermal management of supercritical CO by setting up vortex tubes. 2 The hot and cold fluids of the high-pressure gas drawn out of the compressor are separated, so that the hot fluid is used as the sealing gas of the dry gas seal at the compressor end to avoid liquid condensation on the sealing end face, and the cold fluid is used to cool the high-temperature turbine end sealing cavity to avoid large thermal deformation of the sealing end face and serious corrosion of the sealing parts. This is very important for supercritical CO 2 The high efficiency, low leakage and stable operation of Brayton cycle power generation turbine units are of great significance.

[0016] 2. A supercritical CO2 reactor based on a vortex tube provided in this application 2 Dry gas sealed closed thermal management system, existing supercritical CO 2 The simulation system of dry gas seal at the shaft end of the turbine unit includes a heater for increasing the intake temperature of the compressor end and a heat exchanger or cooling system for reducing the temperature of the sealing chamber at the turbine end. The vortex tube with the function of separating hot and cold fluids is used to replace the energy-consuming elements such as the heater and heat exchanger in the auxiliary system. On the one hand, it improves the operating efficiency and economic efficiency of the system. On the other hand, it also makes the sealing auxiliary system simpler and more compact, expanding its application in some space-constrained occasions. The present application does not require the installation of energy-consuming components such as the medium gas heating device and the cooling system of the dry gas seal pair at the turbine end, nor does it require the installation of a heat insulation device, which reduces the space occupied and greatly improves the overall operating economy of the unit.

[0017] 3. A supercritical CO2 reactor based on a vortex tube provided in this application 2 Dry gas seal closed thermal management system, the outlet temperature of the hot end of the vortex tube is relatively high, and it is used as the sealing gas source of the dry gas seal at the compressor end, which can effectively avoid supercritical CO 2The medium will condense into liquid or even solid dry ice at the dry gas seal end face of the compressor due to the low outlet temperature, which reduces the failure probability of the dry gas seal pair at the compressor end and improves operational reliability.

[0018] 4. A supercritical CO2 reactor based on a vortex tube provided in this application 2 The dry gas sealed closed thermal management system can increase the flow path of the medium gas in the cooling chamber and improve the heat exchange efficiency between the cooling chamber and the turbine end sealing chamber by setting a baffle in the cooling chamber.

[0019] 5. This application provides a supercritical CO based on a vortex tube 2 In the dry gas sealed closed thermal management system, the outlet gas temperature at the cold end of the vortex tube is relatively low, and it is introduced into a cooling chamber with a tortuous flow channel to take away part of the heat in the turbine end sealing chamber, acting as a heat exchanger to cool the turbine end sealing chamber. The lower turbine end sealing chamber temperature helps to reduce the risk of thermal deformation and high-temperature corrosion failure of sealing components. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The following will describe the preferred embodiment in a clear and understandable manner with reference to the accompanying drawings. 2 The above characteristics, technical features, advantages and implementation methods of the dry gas sealed closed thermal management system are further explained:

[0021] Figure 1 It is a schematic diagram of the overall structure of the closed thermal management system of the present application;

[0022] Figure 2 It is a structural cross-sectional view of the high-temperature turbine end seal assembly;

[0023] Figure 3 is a structural cross-sectional view of the compressor end seal assembly;

[0024] Figure 4 It is a schematic diagram of the vortex tube structure.

[0025] Description of Figure Numbers:

[0026] Compressor end sealing assembly 1, impeller locking nut 11, impeller 121, compressor diffuser 122, compressor end sealing cavity 13, compressor wheel back pressure cover 131, sealing cavity air inlet 132, compressor end dynamic ring assembly 14, compressor end dynamic ring 141, compressor end dynamic ring seat 142, compressor end dynamic ring pressing sleeve 143, compressor end static ring assembly 15, compressor end static ring 151, compressor end static ring push ring 152, compressor end static ring spring 153, compressor end spring seat 154, compressor end sealing cavity 16, turbine end sealing assembly 2, high temperature turbine 21, turbine end sealing cavity 22, cooling cavity 222, baffle 223, cooling cavity air inlet 224, cooling cavity air outlet 225, turbine end dynamic ring assembly 23, turbine end dynamic ring 231, turbine end dynamic ring seat 232, turbine end dynamic ring pressing sleeve 233, turbine end static ring Component 24, turbine end static ring 241, turbine end elastic element 242, turbine end static ring seat 243, turbine end locking nut 25, turbine end sealing chamber 26, vortex tube 3, vortex chamber 31, vortex tube air inlet 311, intake fluid 312, hot end tube 32, conical hot end valve 321, vortex tube hot end outlet 322, hot gas 323, cold end tube 33, cold orifice plate 331, vortex tube cold end outlet 332, cold gas 333, medium temperature and pressure measurement and control system 4, vortex tube air inlet pipeline 41, first pressure regulating valve 411, first temperature sensor 412, first pressure sensor 413, vortex tube hot end outlet pipeline 42, second pressure regulating valve 421, second temperature sensor 422, second pressure sensor 423, vortex tube cold end outlet pipeline 43, third temperature sensor 431, fourth temperature sensor 432, third pressure sensor 433. DETAILED DESCRIPTION

[0027] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the specific implementation methods of the present application will be described below with reference to the accompanying drawings. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings and other implementation methods can be obtained based on these drawings without creative work.

[0028] In order to simplify the drawings, only the parts related to the present application are schematically shown in each figure, and they do not represent the actual structure of the product. In addition, in order to simplify the drawings and facilitate understanding, in some figures, only one of the parts with the same structure or function is schematically drawn or marked. In this article, "one" not only means "only one", but also means "more than one".

[0029] It should be further understood that the term “and / or” used in the specification and appended claims refers to any combination and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0030] In this document, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0031] In addition, in the description of the present application, the terms "first", "second", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0032] refer to Figure 1-Figure 4 The present application provides a supercritical CO based on a vortex tube. 2 Dry gas sealed closed thermal management system for supercritical CO 2 The Brayton cycle power generation system includes: a compressor end sealing assembly 1, a turbine end sealing assembly 2, a vortex tube 3 and a medium temperature and pressure measurement and control system 4.

[0033] The compressor end sealing assembly 1 includes a compressor end sealing cavity 16, a compressor end dry gas sealing pair and a compressor end sealing cavity air outlet gap. The compressor end sealing cavity 16 is arranged around the outer periphery of the compressor end dry gas sealing pair, and the compressor end sealing cavity air outlet gap is connected to the compressor end sealing cavity 16.

[0034] The turbine end sealing assembly 2 includes a turbine end sealing chamber 26, a turbine end dry gas sealing pair and a cooling chamber 222. The turbine end sealing chamber 26 is arranged around the outer periphery of the turbine end dry gas sealing pair, and the cooling chamber 222 is arranged on the outer periphery of the turbine end sealing chamber 26. The cooling chamber 222 is provided with a cooling chamber air inlet hole 224 and a cooling chamber air outlet hole 225.

[0035] The vortex tube 3 includes a vortex chamber 31, a hot end tube 32 and a cold end tube 33, and the hot end tube 32 and the cold end tube 33 are respectively connected to the two sides of the vortex chamber 31; the medium temperature and pressure measurement and control system 4 includes a vortex tube air inlet pipeline 41, a vortex tube hot end air outlet pipeline 42 and a vortex tube cold end air outlet pipeline 43.

[0036] The vortex chamber 31 is connected with the outlet of the compressor diffuser 122 through the vortex tube inlet pipeline 41, and the hot gas 323 with a higher temperature flowing out of the hot end pipe 32 enters the compressor end sealing cavity 16 through the vortex tube hot end outlet pipeline 42; the compressor end sealing cavity 16 is connected with the compressor diffuser 122 through the compressor end sealing cavity outlet gap, so that the working medium in the compressor end sealing cavity 16 flows back to the vortex tube inlet pipeline 41.

[0037] The vortex tube cold end air outlet pipe 43 is connected with the cooling chamber air inlet hole 224, so that the cold air 333 with a lower temperature flowing out of the cold end pipe 33 enters the cooling chamber 222; the cooling chamber air outlet hole 225 is connected with the compressor diffuser 122, so that the working medium in the cooling chamber 222 flows back to the vortex tube air inlet pipe 41.

[0038] refer to Figure 1 , Figure 3 In one embodiment, the compressor end sealing assembly 1 also includes a compressor end sealing cavity 13, a compressor end dynamic ring assembly 14, and a compressor end static ring assembly 15. The compressor end sealing cavity 16 is arranged in the compressor end sealing cavity 13. The compressor end dynamic ring assembly 14 includes a compressor end dynamic ring 141. The compressor end static ring assembly 15 includes a compressor end static ring 151. The compressor end dynamic ring 141 and the compressor end static ring 151 constitute the compressor end dry gas sealing pair.

[0039] Specifically, the compressor end moving ring assembly 14 includes a compressor end moving ring 141, a compressor end moving ring seat 142 and a compressor end moving ring compression sleeve 143, and the compressor end static ring assembly 15 includes a compressor end static ring 151, a compressor end static ring push ring 152, a compressor end static ring spring 153 and a compressor end spring seat 154. The compressor end moving ring 141 and the compressor end static ring 151 form a compressor end dry gas seal pair. The impeller 121, the compressor end moving ring seat 142 and the compressor end moving ring compression sleeve 143 are axially fixed to the rotor through the impeller locking nut 11, and the compressor end moving ring 141 is fixedly installed on the compressor end moving ring seat 142 and is axially compressed through the compressor end moving ring compression sleeve 143. The compressor end static ring 151 is installed in a floating manner on the compressor end spring seat 154. A compressor end static ring push ring 152 and a compressor end static ring spring 153 are provided axially between the compressor end static ring 151 and the compressor end spring seat 154. The compressor end static ring spring 153 is used to provide auxiliary closing force for the compressor end static ring 151. The compressor end sealing cavity 13 is provided with a sealing cavity air inlet 132. The hot gas 323 flowing out of the hot end outlet 322 of the vortex tube enters the compressor end sealing cavity 16 after passing through the sealing cavity air inlet 132. Since the hot gas 323 has a high temperature, when it leaks and flows through the compressor end dry gas seal secondary end face, the medium gas is not easy to condense in the liquid phase or even form solid dry ice due to the low temperature at the outlet of the sealing end face, thereby reducing the probability of phase change failure of the compressor end dry gas seal and improving the reliability and stability of the sealing operation.

[0040] refer to Figure 1 , Figure 2 In one embodiment, the turbine end sealing assembly 2 also includes a turbine end sealing cavity 22, a turbine end dynamic ring assembly 23 and a turbine end static ring assembly 24, the turbine end sealing cavity is arranged in the turbine end sealing cavity 22, the cooling cavity 222 is opened on the turbine end sealing cavity 22, the turbine end dynamic ring assembly 23 includes a turbine end dynamic ring 231, the turbine end static ring assembly 24 includes a turbine end static ring 241, the turbine end dynamic ring 231 and the turbine end static ring 241 constitute the turbine end dry gas sealing pair.

[0041] Specifically, the turbine end moving ring assembly 23 includes a turbine end moving ring 231, a turbine end moving ring seat 232, and a turbine end moving ring pressing sleeve 233. The turbine end stationary ring assembly 24 includes a turbine end stationary ring 241, a turbine end elastic element 242, and a turbine end stationary ring seat 243. The turbine end moving ring 231 and the turbine end stationary ring 241 form a turbine end dry gas seal pair. The high-temperature turbine 21, the turbine end moving ring seat 232, and the turbine end moving ring pressing sleeve 233 are axially fixed to the rotor through the turbine end locking nut 25. The turbine end moving ring 231 is fixedly mounted on the turbine end moving ring seat 232 and is axially pressed by the turbine end moving ring pressing sleeve 233. The turbine end stationary ring 241 is floatingly mounted on the turbine end stationary ring seat 243. The turbine end elastic element 242 is used to provide auxiliary closing force to the turbine end stationary ring 241. The turbine end elastic element 242 preferably adopts a metal bellows to adapt to high temperature environment. A cooling chamber 222 is provided on the turbine end sealing chamber 22. The cooling chamber 222 is not connected to the turbine end sealing chamber 26. A plurality of staggered baffles 223 are used in the cooling chamber 222 to form a tortuous flow path to enhance the heat exchange effect. The cooling chamber 222 is connected to the vortex tube cold end outlet pipe 43 through the cooling chamber air inlet 224, and the cooling chamber 222 is connected to the compressor diffuser 122 through the cooling chamber outlet 225. The low-temperature cold air 333 flowing out from the vortex tube cold end outlet 332 enters the cooling chamber 222 from the cooling chamber air inlet 224, flows along the tortuous flow path formed by the baffle 223 toward the cooling chamber outlet 225, and continuously absorbs the heat derived from the high-temperature turbine end sealing chamber 26 during the flow, thereby gradually increasing the temperature of the fluid. At the same time, the ambient temperature in the turbine end sealing chamber 26 decreases, thereby improving the operating environment of the turbine end dry gas seal and reducing the thermal deformation and high-temperature corrosion strength of the sealing components.

[0042] refer to Figure 1 , Figure 3 In one embodiment, the compressor end sealing assembly 1 further includes a compressor wheel back pressure cover 131, which is disposed between the compressor end sealing cavity 16 and the impeller 121 of the compressor, and an air outlet gap of the compressor end sealing cavity is formed between the compressor wheel back pressure cover 131 and the impeller 121.

[0043] refer to Figure 4It can be understood that the structure of the vortex tube 3 is the prior art. Specifically, the vortex tube 3 is composed of a vortex chamber 31, a hot end tube 32 and a cold end tube 33. The intake fluid 312 drawn from the compressor diffuser 122 enters the vortex chamber 31 tangentially through the vortex tube inlet 311 and generates a cyclone. The cyclone-generating fluid enters the hot end tube 32 and flows in a spiral shape along the inner wall toward the vortex tube hot end outlet 322. During the flow, on the one hand, the temperature rises due to the viscous friction between the fluid and the tube wall, and on the other hand, the energy of the inner layer of the hot end tube 32 gradually transfers to the outside, and the temperature of the outer layer of the fluid rises, becoming hot gas 323 with a higher temperature and entering the hot end outlet pipe 42 of the vortex tube. The fluid in the hot end tube 32 becomes the inner fluid after encountering the conical hot end valve 321 in the vortex tube 3 and gradually flows toward the cold end outlet 332 of the vortex tube. During the flow, the fluid is cooled due to the heat transfer to the outer fluid. At the same time, the temperature is further reduced when passing through the cold hole plate 331, and becomes cold air 333 with a lower temperature and enters the cold end outlet pipe 43 of the vortex tube. The vortex tube 3 is a non-energy-consuming device. Through the ingenious design of the internal vortex chamber 31, the cold end tube 33 and the hot end tube 32 structure, it realizes the significant cooling of the cold end fluid and the significant heating of the hot end fluid. Compared with the heater, heat exchanger and other equipment in the previous dry gas seal auxiliary system, it has the advantages of good operation economy and simple and compact structure.

[0044] refer to Figure 1 In one embodiment, the vortex tube inlet pipeline 41 is provided with a first pressure regulating valve 411, a first temperature sensor 412 and a first pressure sensor 413, the vortex tube hot end outlet pipeline 42 is provided with a second pressure regulating valve 421, a second temperature sensor 422 and a second pressure sensor 423, the vortex tube cold end outlet pipeline 43 is provided with a third temperature sensor 431, and the communication path between the cooling chamber outlet hole 225 and the compressor diffuser 122 is provided with a fourth temperature sensor 432 and a third pressure sensor 433.

[0045] Specifically, the first temperature sensor 412 and the first pressure sensor 413 are used to monitor whether the temperature and pressure of the vortex tube inlet pipeline 41 are normal. If they are not normal, the first pressure regulating valve 411 is required to adjust. The second temperature sensor 422 and the second pressure sensor 423 are used to monitor the pressure and temperature of the vortex tube hot end outlet pipeline 42 to ensure that the temperature of the vortex tube hot end outlet pipeline 42 is far away from CO 2 The critical temperature of the vortex tube is set, and the pressure of the vortex tube hot end outlet pipe 42 is adjusted to be close to the pressure of the cooling chamber outlet 225 by adjusting the second pressure regulating valve 421. The third temperature sensor 431 is used to monitor the temperature of the cold fluid near the vortex tube cold end outlet 332 to prevent the cold fluid from changing phase due to too low temperature.

[0046] It is worth noting that the vortex tube 3 is the core component of the entire closed thermal management system. The medium gas from the outlet of the compressor diffuser 122 enters the vortex chamber 31 of the vortex tube 3 after passing through the vortex tube inlet pipe 41, and is heated up in the hot end pipe 32 to become hot gas 323 and cooled down in the cold end pipe 33 to become cold gas 333. The hot gas 323 passes through the vortex tube hot end outlet pipe 42 and enters the compressor end sealing cavity 16. A part of the fluid leaks and flows from the gap between the end faces of the compressor end dynamic ring 141 and the compressor end static ring 151, and the other part leaks and flows. Part of the fluid flows back to the compressor diffuser 122 through the gap between the compressor wheel back pressure cover 131 and the impeller 121 to form the first closed cycle; the cold air 333 enters the cooling chamber 222 opened on the turbine end sealing chamber 22 after passing through the vortex tube cold end outlet pipe 43, and gradually takes away part of the heat in the turbine end sealing chamber 26 when flowing in the tortuous flow channel of the cooling chamber 222 to achieve cooling of the cavity environment, and the gas flowing out of the cooling chamber 222 also flows back to the compressor diffuser 122 through the gas pipeline to form the second closed cycle. Through the reasonable design of the internal structure of the vortex tube 3, the hot end outlet temperature and the cold end outlet temperature can be regulated within a certain range; through the design of the tortuous flow channel in the cooling chamber 222, the temperature rise of the cold end gas after passing through the cooling chamber 222 can be controlled, and the outlet temperature of the cooling chamber 222 is basically consistent with the mainstream temperature in the compressor diffuser 122. Pressure regulating valves and pressure sensors for gas pressure control and monitoring, as well as temperature sensors for temperature monitoring are arranged on the vortex tube inlet pipeline 41, the vortex tube cold end outlet pipeline 43 and the vortex tube hot end outlet pipeline 42 to realize real-time online control and monitoring of the closed thermal management system.

[0047] It should be noted that the above embodiments can be freely combined as needed. The above are only preferred implementations of the present application. 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 application, and these improvements and modifications should also be regarded as the protection scope of the present application.

Claims

1. A supercritical CO2 dry gas sealed closed thermal management system based on a vortex tube, characterized in that: include: A compressor end sealing assembly 1, comprising a compressor end sealing cavity 16, a compressor end dry gas sealing pair and a compressor end sealing cavity outlet gap, wherein the compressor end sealing cavity 16 is arranged around the periphery of the compressor end dry gas sealing pair, and the compressor end sealing cavity outlet gap is communicated with the compressor end sealing cavity 16; The turbine end seal assembly 2 comprises a turbine end seal cavity 26, a turbine end dry gas seal pair and a cooling cavity 222, wherein the turbine end seal cavity 26 is arranged around the outer periphery of the turbine end dry gas seal pair, the cooling cavity 222 is arranged at the outer periphery of the turbine end seal cavity 26, and the cooling cavity 222 is provided with a cooling cavity air inlet hole 224 and a cooling cavity air outlet hole 225; The vortex tube 3 comprises a vortex chamber 31, a hot end tube 32 and a cold end tube 33, wherein the hot end tube 32 and the cold end tube 33 are respectively connected to two sides of the vortex chamber 31; The medium temperature and pressure measurement and control system 4 includes a vortex tube air inlet pipeline 41, a vortex tube hot end air outlet pipeline 42 and a vortex tube cold end air outlet pipeline 43; The vortex chamber 31 is connected to the outlet of the compressor diffuser 122 through the vortex tube inlet pipeline 41, and the hot gas 323 with a relatively high temperature flowing out of the hot end pipe 32 enters the compressor end sealed cavity 16 through the vortex tube hot end outlet pipeline 42; the compressor end sealed cavity 16 is connected to the compressor diffuser 122 through the compressor end sealed cavity outlet gap, so that the working medium in the compressor end sealed cavity 16 flows back to the vortex tube inlet pipeline 41; The vortex tube cold end air outlet pipe 43 is connected with the cooling chamber air inlet hole 224, so that the cold air 333 with a lower temperature flowing out of the cold end pipe 33 enters the cooling chamber 222; the cooling chamber air outlet hole 225 is connected with the compressor diffuser 122, so that the working medium in the cooling chamber 222 flows back to the vortex tube air inlet pipe 41.

2. A supercritical CO2 dry gas sealed closed thermal management system based on a vortex tube according to claim 1, characterized in that: The compressor end sealing assembly 1 also includes a compressor end sealing cavity 13, a compressor end dynamic ring assembly 14, and a compressor end static ring assembly 15. The compressor end sealing cavity 16 is arranged in the compressor end sealing cavity 13. The compressor end dynamic ring assembly 14 includes a compressor end dynamic ring 141. The compressor end static ring assembly 15 includes a compressor end static ring 151. The compressor end dynamic ring 141 and the compressor end static ring 151 constitute the compressor end dry gas sealing pair.

3. A supercritical CO2 dry gas sealed closed thermal management system based on a vortex tube according to claim 2, characterized in that: The turbine end sealing assembly 2 also includes a turbine end sealing cavity 22, a turbine end dynamic ring assembly 23 and a turbine end static ring assembly 24. The turbine end sealing cavity is arranged in the turbine end sealing cavity 22. The cooling cavity 222 is opened on the turbine end sealing cavity 22. The turbine end dynamic ring assembly 23 includes a turbine end dynamic ring 231. The turbine end static ring assembly 24 includes a turbine end static ring 241. The turbine end dynamic ring 231 and the turbine end static ring 241 constitute the turbine end dry gas sealing pair.

4. A supercritical CO2 dry gas sealed closed thermal management system based on a vortex tube according to claim 3, characterized in that: The compressor end sealing assembly 1 also includes a compressor wheel back pressure cover 131, which is arranged between the compressor end sealing cavity 16 and the impeller 121 of the compressor, and the compressor end sealing cavity air outlet gap is formed between the compressor wheel back pressure cover 131 and the impeller 121.

5. A supercritical CO2 dry gas sealed closed thermal management system based on a vortex tube according to any one of claims 1 to 4, characterized in that: A baffle 223 is disposed in the cooling cavity 222 .

6. A supercritical CO2 dry gas sealed closed thermal management system based on a vortex tube according to claim 5, characterized in that: The vortex tube air inlet pipeline 41 is provided with a first pressure regulating valve 411, a first temperature sensor 412 and a first pressure sensor 413, the vortex tube hot end air outlet pipeline 42 is provided with a second pressure regulating valve 421, a second temperature sensor 422 and a second pressure sensor 423, the vortex tube cold end air outlet pipeline 43 is provided with a third temperature sensor 431, and the communication path between the cooling chamber air outlet hole 225 and the compressor diffuser 122 is provided with a fourth temperature sensor 432 and a third pressure sensor 433.

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