Supercritical CO2 turbine inter-shaft cooling test system

Abstract

The present disclosure provides a supercritical carbon dioxide turbine inter-shaft cooling test system, comprising: a rotor, wherein micro-grooves are symmetrically opened on the surface of the rotor in the axial direction, and a plurality of temperature measuring points are evenly distributed in the micro-grooves; a rotary cooling device, wherein both ends have openings, and the rotor is inserted into the rotary cooling device to form a cooling cavity with the rotary cooling device; interfaces for supercritical carbon dioxide to enter and be discharged are respectively arranged along the circumferential direction of the rotary cooling device; an electromagnetic heating device, which is detachably connected to one end of the rotary cooling device, and a heating cavity is arranged on the inner surface of the electromagnetic heating device, and the head end of the rotor is close to the heating cavity; a sealing and temperature measuring device, which is electrically connected to the plurality of temperature measuring points; one end of the sealing and temperature measuring device is detachably connected to the other end of the rotary cooling device, and the other end cooperates with the tail end of the rotor to form a static seal.

Description

Technical Field

[0001] The present invention relates to the technical field of supercritical carbon dioxide Brayton cycle power generation, and in particular to a supercritical carbon dioxide turbine inter-shaft cooling test system. Background Art

[0002] Supercritical carbon dioxide (SCO2) Brayton cycle power generation technology uses SCO2 as the working fluid, which has excellent environmental friendliness and high energy utilization. The high-temperature turbine is the energy conversion device of the SCO2 Brayton cycle power generation system. The performance of the high-temperature turbine directly affects the system cycle efficiency. For the high-temperature turbine, the high-pressure dynamic seal during high-speed rotation is the bottleneck that directly affects the turbine efficiency.

[0003] In the related technology, the SCO2 turbine inter-shaft cooling test system uses dry gas seals as the shaft end dynamic seals of the SCO2 turbine. However, due to the poor temperature resistance of dry gas seals, when combined with high-temperature turbines, it is easy to overheat due to heat accumulation, resulting in equipment damage. Therefore, efficient cooling is required between the high-temperature turbine and the seal to quickly remove the heat.

[0004] However, there is no experimental system available to study the cooling technology of SCO2 high-temperature turbine. Therefore, it is necessary to design a suitable cooling test system for the cooling structure of SCO2 high-temperature turbine to verify the cooling effect and study the cooling characteristics. Summary of the invention

[0005] In view of this, the present disclosure provides a supercritical carbon dioxide turbine inter-shaft cooling test system, comprising: a rotor, wherein micro grooves are symmetrically opened on the surface of the rotor in the axial direction, and a plurality of temperature measuring points are evenly distributed in the micro grooves; a rotary cooling device, wherein both ends have openings, and the rotor is inserted into the rotary cooling device to form a cooling cavity with the rotary cooling device; interfaces for supercritical carbon dioxide to enter and be discharged are respectively provided along the circumferential direction of the rotary cooling device; an electromagnetic heating device, which is detachably connected to one end of the rotary cooling device, and a heating cavity is provided on the inner surface of the electromagnetic heating device, and the head end of the rotor is close to the heating cavity; a sealing and temperature measuring device, which is electrically connected to the plurality of temperature measuring points; one end of the sealing and temperature measuring device is detachably connected to the other end of the rotary cooling device, and the other end cooperates with the tail end of the rotor to form a static seal.

[0006] Preferably, the rotary cooling device includes a cooling inner ring and a cooling outer ring nested on the cooling inner ring, the two ends of the cooling outer ring are respectively detachably connected to the electromagnetic heating device, the sealing and temperature measuring device, the rotor is inserted into the rotary cooling device and forms a cooling cavity with the cooling inner ring; a plurality of air inlets and exhaust ports are circumferentially arranged on the cooling outer ring to form an external interface of the rotary cooling device; an air inlet cavity and an exhaust cavity are arranged on the inner surface of the cooling inner ring, and a plurality of air holes are evenly distributed circumferentially on the air inlet cavity and the exhaust cavity of the cooling inner ring to form an inlet and an outlet of the cooling cavity, and the inlet and the outlet of the cooling cavity are respectively connected to the air inlet and the exhaust port of the cooling outer ring.

[0007] Preferably, a diverter channel is provided in the cooling outer ring, one end of the diverter channel is communicated with the inlet of the cooling cavity, and the other end of the diverter channel is communicated with the air inlet of the cooling outer ring.

[0008] Preferably, the sealing and temperature measuring device includes a bearing seat, a slip ring and a magnetic coupling, wherein: the two ends of the bearing seat are detachably connected to the other end of the rotating cooling device and the magnetic coupling, and the magnetic coupling cooperates with the tail end of the rotor to form a static seal; the slip ring is installed between the front and rear bearings of the bearing seat, and is installed on the rotor, and is electrically connected to multiple temperature measuring points.

[0009] Preferably, a plurality of cooling channels are provided in the bearing seat.

[0010] Preferably, the supercritical carbon dioxide turbine inter-shaft cooling test system also includes a supercritical carbon dioxide gas supply circulation device, which is respectively connected to the interfaces for supercritical carbon dioxide entry and exhaust on the rotary cooling device to realize the circulation of supercritical carbon dioxide through the cooling cavity and cool the rotor.

[0011] Preferably, the supercritical carbon dioxide gas supply circulation device includes a supercritical carbon dioxide supply device, an electric booster pump, an electric heater, a switching valve, a check valve, a water cooler, an inlet pipeline, an outlet pipeline and a bypass pipeline; wherein: on the inlet pipeline, the electric booster pump, the electric heater and the switching valve are connected in series in sequence along the direction of the supercritical carbon dioxide; on the outlet pipeline, the check valve and the water cooler are connected in series in sequence along the direction of the supercritical carbon dioxide; wherein, the interfaces for the supercritical carbon dioxide to enter and discharge on the rotary cooling device are respectively connected to the output end of the switching valve and the input end of the check valve; the bypass pipeline is respectively connected to the output end of the switching valve and the input end of the check valve.

[0012] Preferably, the supercritical carbon dioxide gas supply circulation device further comprises a regulating valve, which is arranged between the electric booster pump and the electric heater.

[0013] Preferably, the supercritical carbon dioxide gas supply circulation device further comprises a storage tank, which is arranged between the water cooler and the supercritical carbon dioxide supply device, wherein the storage tank is connected to the first vent valve.

[0014] Preferably, the supercritical carbon dioxide turbine inter-shaft cooling test system further comprises a second vent valve, and the second vent valve is connected to the rotary cooling device.

[0015] The present disclosure provides a supercritical carbon dioxide turbine inter-shaft cooling test system, which has at least the following beneficial effects:

[0016] 1. The present invention not only can flexibly arrange the positions of temperature measurement points but also improve the temperature measurement accuracy by designing structures such as slip rings and micro grooves.

[0017] 2. The rotary cooling device disclosed in the present invention can be detachably mounted on the rotor, which is convenient for manufacturing, assembling and installing the rotor. The rotary cooling device includes a cooling inner ring and a cooling outer ring detachably nested on the cooling inner ring, which is convenient for flexibly replacing the inner ring to change the size of the test channel and realize the test implementation of channels with various geometric parameters.

[0018] 3. The present invention converts the shaft end dynamic seal into a static seal through the isolation effect of the isolation plate, so that the rotary cooling system is completely closed, thereby achieving stable operation with zero leakage.

[0019] 4. The present disclosure provides a method for heating a rotor using the principle of electromagnetic induction, which has a fast heating speed and a stable thermal boundary. In addition, the electromagnetic coil can be flexibly selected according to the needs to meet different heating requirements.

[0020] 5. The present invention adopts self-lubricating ceramic bearings, which can meet the support requirements under high-pressure environments and avoid complex oil circuit design and lubricating oil systems.

[0021] 6. The present invention provides multiple water channels at the bottom of the bearing seat to cool the bearing, thereby avoiding bearing damage and extending the service life of the test system.

[0022] 7. The present invention couples the temperature measuring device, the sealing device and the bearing seat to save space and make the test system structure more compact. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 A cross-sectional view schematically shows the structure of a supercritical carbon dioxide turbine inter-shaft cooling test system according to an embodiment of the present disclosure;

[0024] Figure 2 A schematic diagram of the matching structure of the rotor and the slip ring in an embodiment of the present disclosure is shown.

[0025] Description of Reference Numerals

[0026] 11-sealed housing 111-screw 12-electromagnetic coil

[0027] 13-lead seal 14-heating chamber 20-rotor

[0028] 201-micro groove 202-key groove 31-cooling inner ring

[0029] 311-intake cavity 312-exhaust cavity 313-cooling cavity

[0030] 32- cooling outer ring 321- air inlet 322- diversion channel

[0031] 323-exhaust port 41-bearing seat 411-cooling channel

[0032] 412-Self-lubricating ceramic bearing 42-Cover plate 43-Slip ring

[0033] 431-slip ring stator 432-slip ring rotor 50-magnetic coupling

[0034] 51-external magnet 52-isolation plate 53-internal magnet

[0035] 61-Supercritical carbon dioxide supply device 62-Electric booster pump

[0036] 63- regulating valve 64- electric heater 65- switching valve

[0037] 66- Check valve 67- Water cooler 68- Storage tank

[0038] 611-inlet pipeline 612-exhaust pipeline 613-bypass pipeline

[0039] 70-driving device 71-mounting seat DETAILED DESCRIPTION

[0040] In order to make the objectives, technical solutions and advantages of the present disclosure more clearly understood, the present disclosure is further described in detail below in combination with specific embodiments and with reference to the accompanying drawings.

[0041] It should be noted that in the drawings or descriptions, similar or identical parts all use the same figure numbers. The implementation methods not shown or described in the drawings are forms known to those of ordinary skill in the art. In addition, although demonstrations of parameters containing specific values ​​may be provided herein, it should be understood that the parameters do not need to be exactly equal to the corresponding values, but can be approximated to the corresponding values ​​within an acceptable error tolerance or design constraint. In addition, the directional terms mentioned in the following embodiments, such as "up", "down", "front", "back", "left", "right", "inside", "outside", etc., are only reference directions of the drawings. Therefore, the directional terms used are used to illustrate and are not used to limit the present disclosure.

[0042] In addition, relational terms such as "first" and "second", etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "comprises", "comprising", or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article, or device that includes a series of elements includes not only those elements, but also other elements that are not explicitly listed, or also includes elements that are inherent to such process, method, article, or device. In the absence of further restrictions, an element defined by the statement "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or device that includes the element.

[0043] The characteristics and performance of the supercritical carbon dioxide turbine inter-shaft cooling test system disclosed in the present invention are further described in detail below in conjunction with the embodiments.

[0044] Figure 1 A schematic structural diagram of a supercritical carbon dioxide turbine inter-shaft cooling test system in an embodiment of the present disclosure is shown.

[0045] like Figure 1 As shown, in this embodiment, a supercritical carbon dioxide turbine inter-shaft cooling test system is provided, and the supercritical carbon dioxide turbine inter-shaft cooling test system includes: an electromagnetic heating device, a rotor 20, a rotary cooling device, a sealing and temperature measuring device, a driving device, and a supercritical carbon dioxide gas supply circulation device. Among them, the electromagnetic heating device, the rotary cooling device, the sealing and temperature measuring device, the driving transposition and other structures form a closed experimental body, and the rotary cooling device is provided with a supercritical carbon dioxide inlet and outlet interface connected to the supercritical carbon dioxide gas supply circulation device.

[0046] The electromagnetic heating device includes a sealed shell 11 and an electromagnetic coil 12. The sealed shell 11 is detachably connected to one end of the rotary cooling device, and a heating chamber 14 is provided on the inner surface of the sealed shell 11, and the head end of the rotor 20 is close to the heating chamber 14. The electromagnetic coil 12 is installed in the heating chamber 14 through a lead seal 13 to heat the rotor 20 to a preset temperature (i.e., the test temperature), wherein the preset temperature can be set according to the test needs and is not limited here. In this embodiment, electromagnetic eddy currents are generated in the heated surface of the rotor 20 close to the electromagnetic coil 12 by a non-contact electromagnetic heating method, thereby generating self-heating, realizing rapid heating of the heated surface of the head end of the rotor 20, and providing stable experimental thermal boundary conditions. In addition, electromagnetic heating can provide a variety of different rotor heating surface temperatures by stepless power regulation, so that it can adapt to different test temperature requirements.

[0047] The rotary cooling device is the core device for the supercritical carbon dioxide rotary cooling test, which includes a cooling inner ring 31 and a cooling outer ring 32, wherein the cooling inner ring 31 is installed and nested in the cooling outer ring through a thread (not shown in the figure). Both ends of the cooling inner ring 31 and the cooling outer ring 32 have openings for the rotor 20 to extend therein. When the rotor 20 is inserted into the rotary cooling device, it forms a cooling cavity 313 with the cooling inner ring 31. Figure 1 As shown, the left end of the cooling outer ring 32 is connected to the sealing shell 11 of the electromagnetic heating device, for example, by a screw 111, and the right end of the cooling outer ring 32 can be connected to the bearing seat 41 in the sealing and temperature measuring device, for example, by a flange. The various structures can be connected, for example, by threads, or by a combination of end teeth and pull rods, or by splines and pull rods, pins, etc. The specific connection method can be flexibly selected according to the experimental requirements and is not limited here.

[0048] In this embodiment, the cooling inner and outer rings of the rotating cooling device adopt a detachable nesting design, which is not only convenient for manufacturing, assembling and installing the rotor, but also convenient for flexibly replacing the inner ring to change the size of the test channel, thereby realizing the test implementation of channels with various geometric parameters.

[0049] According to the embodiment of the present disclosure, a plurality of air inlets 321 and exhaust ports 323 are respectively provided along the circumference of the cooling outer ring 32, which are respectively connected to the supercritical carbon dioxide supply circulation device to allow the supercritical carbon dioxide to enter and be discharged. For ease of manufacturing and taking into account factors such as the cooling gas flow rate, preferably, in this embodiment, two air inlets 321 and exhaust ports 323 are respectively symmetrically provided along the circumference of the cooling outer ring 32.

[0050] The inner surface of the cooling inner ring 31 is provided with an air inlet cavity 311 and an air outlet cavity 312. A plurality of air holes are evenly distributed in the circumference of the air inlet cavity 311 and the air outlet cavity 312 of the cooling inner ring 31 to form the inlet and outlet of the cooling cavity 313. The inlet and outlet of the cooling cavity 313 are respectively connected with the air inlet 321 and the air outlet 323 of the cooling outer ring 32. The inlet of the cooling cavity 313 is preferably a constriction with a sudden change in radial size to increase the flow rate of supercritical carbon dioxide when it is discharged from the air inlet hole on the air inlet cavity 311. In other embodiments, a structure of equal diameter may also be used.

[0051] In the embodiment disclosed herein, the inlet and outlet of the cooling chamber 313 are staggered so that the supercritical carbon dioxide entering and exiting are drained separately, thereby avoiding interference between the supercritical carbon dioxide entering and exiting, and forming turbulence in the cooling chamber 313 that affects the heat dissipation of the rotor 20 and the normal circulation of the cooling gas, thereby ensuring that the supercritical carbon dioxide can circulate smoothly. Figure 1As shown, the outlet of the cooling chamber 313 is located at the left end, and the inlet of the cooling chamber 313 is located at the right end, so that the supercritical carbon dioxide can flow from the right end to the left end of the rotary cooling transpose, that is, the direction in which the supercritical carbon dioxide flows in the cooling chamber 313 is opposite to the rotation direction of the rotor 20, so that the supercritical carbon dioxide can evenly dissipate the heat of the rotor 20 located in the cooling chamber 313, thereby ensuring the heat dissipation effect and effectively controlling the temperature rise of the rotor.

[0052] In some embodiments of the present disclosure, a shunt groove 322 is further provided in the cooling outer ring 32, one end of the shunt groove 322 is connected to the inlet or outlet of the cooling cavity 313, and the other end is connected to the air inlet 321 or the exhaust port 323 of the cooling outer ring 32. Supercritical carbon dioxide is shunted through the shunt groove 322 of the cooling outer ring 32 to the multiple air holes of the cooling inner ring 31 and enters the air inlet cavity 311, so that the circumferential air intake and exhaust are more uniform.

[0053] Please continue to refer to Figure 1 In this embodiment, the supercritical carbon dioxide rotation cooling test is specifically carried out in the cooling chamber 313. Figure 1 The arrows in the diagram schematically show the circulation flow direction of supercritical carbon dioxide in the cooling chamber 313. Specifically, after supercritical carbon dioxide enters the rotary cooling device from the multiple air inlets 321 of the cooling outer ring 32, it enters the cooling chamber 313 through the air inlet holes on the air inlet chamber 311 of the cooling inner ring 32, and cools the rotor 20 in the cooling chamber 313, that is, cooling gas is introduced into the cooling chamber 313 to exchange heat with the rotor 20, so as to reduce the temperature of the rotor 20. At this time, the test parameters such as the temperature, pressure, rotation speed, and cooling gas flow rate in the cooling chamber 313 can be monitored. In addition, according to the test needs, the detachable cooling inner and outer ring structures can be used to set different axial lengths of the cooling area, the height of the cooling area gap, the rotor radius, etc., so as to obtain the relevant test parameters required for the cooling test, so as to verify the cooling effect and study the cooling characteristics.

[0054] Please continue to refer to Figure 1 ,like Figure 1 As shown, the sealing and temperature measuring device includes a bearing seat 41, a slip ring 43, a cover plate 42 and a magnetic coupling 50. The left end of the bearing seat 41 and the right end of the cooling outer ring 32 can be connected by, for example, a flange, and the right end of the bearing seat 41 and the isolation plate 52 in the magnetic coupling 50 can be connected by, for example, threads. The slip ring 43 is installed between the front and rear bearings 412 of the bearing seat 41, the slip ring rotor 432 is installed on the rotor 20 by threads, and the slip ring stator 431 is installed on the cover plate 42 at the upper end of the bearing seat 41.

[0055] The magnetic coupling 50 is composed of an inner magnet 53, an isolation plate 52 and an outer magnet 51. The isolation plate 52 is installed at the right end of the bearing seat 41, and the inner magnet 53 is arranged on the inner side of the isolation plate 52 and is installed at the tail end of the rotor 20 (such as Figure 1 As shown, a keyway 202 is provided at the tail end of the rotor, and the external magnet 51 is mounted on the output shaft head of a driving device 70, such as a high-speed motor, and the driving device 70 can be fixed by a mounting seat 71. In this embodiment, the shaft end dynamic seal can be converted into a static seal by the isolation effect of the isolation plate 52, so that the rotating cooling device is completely closed, thereby achieving stable operation with zero leakage. In addition, in this embodiment, the magnetic coupling technology is used to drive the internal magnet 53 on the rotor 20 to ensure that the rotor 20 can operate normally at the speed required by the experiment in a closed environment.

[0056] In this embodiment, the bearing 412 between the bearing seats 41 can adopt a self-lubricating ceramic bearing, which can meet the support requirements under high pressure environment, reduce the difficulty of sealing the test section, and also avoid complex oil circuit design and lubricating oil system. In addition, in the disclosed embodiment, a multi-channel cooling channel 411 can be opened at the lower part of the bearing seat 41, and the multi-channel cooling channel does not interfere with the rotating cooling test area, and a cooling medium, such as cooling water or other suitable cooling medium, can be introduced into the multi-channel cooling channel to cool the bearing 411, thereby avoiding bearing damage.

[0057] Figure 2 A schematic diagram of the matching structure of the rotor and the slip ring in the embodiment of the present disclosure is further shown.

[0058] Please refer to Figure 1 and Figure 2 The rotor 20 in this embodiment is cylindrical, and micro grooves 201 are symmetrically opened on the surface of the rotor 20 in the axial direction. The opening length of the micro groove 201 can be, for example, from the head end of the rotor 20 to the place where the slip ring 43 is installed on the rotor 20. Different lengths can also be set according to experimental needs in other embodiments of the present disclosure.

[0059] There are multiple temperature measurement points evenly distributed in the micro slot 201. The multiple temperature measurement points can be realized by, for example, arranging multiple micro thermocouples in the micro slot 201. For example, the micro thermocouples can be installed in the mounting holes in the micro slot 201 by high-temperature thermosetting adhesive. The signal line of the micro thermocouple is directly connected to the slip ring 43 through the micro slot 201 to transmit the temperature measurement signal to the stationary structure such as the casing. The embodiment of the present disclosure can flexibly arrange the positions of the temperature measurement points by designing structures such as the slip ring 43 and the micro slot 201, realize multi-point temperature measurement, and improve the temperature measurement accuracy.

[0060] It should be noted that the rotors described in this disclosure and Figure 1 and Figure 2 The shape, structure and size of the rotor 20 shown in the figure are only exemplary to help those skilled in the art understand the technical solution of the present disclosure, and are not intended to limit the protection scope of the present disclosure. The shape, size and structure of the rotor can be changed according to the test needs. For example, in some other embodiments, the shape of the rotor can be a disc or other shapes, which are not limited here.

[0061] like Figure 1 As shown, in this embodiment, by coupling the temperature measuring device, the sealing device and the bearing seat, space is saved, making the entire test system more compact.

[0062] Please continue to refer to Figure 1 ,like Figure 1 As shown, the supercritical carbon dioxide turbine inter-shaft cooling test system also includes a supercritical carbon dioxide gas supply circulation device. An inlet pipeline 611 is connected between the supercritical carbon dioxide gas supply circulation device and the air inlet 321 of the cooling outer ring 32, and an outlet pipeline 612 is connected between the supercritical carbon dioxide gas supply circulation device and the exhaust port 323 of the cooling outer ring 32, so as to achieve the purpose of recycling supercritical carbon dioxide.

[0063] Specifically, on the inlet pipeline 611, an electric booster pump 62, an electric heater 64 and a switching valve 65 are sequentially connected in series along the direction in which the supercritical carbon dioxide advances. Among them, the electric booster pump 62 is used to pump the supercritical carbon dioxide into the electric heater 64, and at the same time pressurize the supercritical carbon dioxide. The electric heater 64 heats the pumped supercritical carbon dioxide to a preset temperature (wherein the preset temperature can be set by itself according to the needs of the test, and is not limited here), and sends it to the rotary cooling device. The switching valve 65 is used to switch different circulation loops according to the different stages of the test to avoid sending the supercritical carbon dioxide that has not reached the preset temperature into the rotary cooling device.

[0064] On the discharge pipeline 612, a check valve 66 and a water cooler 67 are connected in series in the direction of the supercritical carbon dioxide. The check valve 66 plays a one-way role, which can prevent the supercritical carbon dioxide in the rotating cooling device from flowing back into the supercritical carbon dioxide supply device 61. When the temperature of the supercritical carbon dioxide increases after heat exchange with the rotor 20, it can be cooled by the water cooler 67, and the cooled supercritical carbon dioxide is stored in the supercritical carbon dioxide supply device 61.

[0065] In addition, the above-mentioned supercritical carbon dioxide gas supply circulation device is also connected to a bypass pipeline 613 before the output end of the switching valve 65 and the input end of the check valve 66. Before the test phase, the supercritical carbon dioxide has not reached the preset temperature. At this time, the switching valve 62 can be switched to connect the entry pipeline 611 with the bypass pipeline 613, and the connection between the supercritical carbon dioxide circulation loop and the rotary cooling device is disconnected. The supercritical carbon dioxide that has not reached the preset temperature is circulated back to the supercritical carbon dioxide supply device 61 through the bypass pipeline 613 through the check valve 66 and the water cooler 67 (the water cooler 67 is not started at this time), so that the supercritical carbon dioxide that has not reached the preset temperature can be avoided from being sent to the rotary cooling device. When the supercritical carbon dioxide reaches the preset temperature, it is connected to the air inlet 321 and the exhaust port 323 of the cooling outer ring 32 by switching the switching valve 65, and the connection with the bypass pipeline is disconnected. At this time, the supercritical carbon dioxide that has reached the preset temperature can enter the rotary cooling device, and then the test test of rotary cooling under different working conditions can be realized.

[0066] In the disclosed embodiment, the supercritical carbon dioxide gas supply circulation device further includes a regulating valve 63, which is disposed between the electric booster pump 62 and the electric heater 64. The regulating valve 63 is used to regulate the flow rate of the supercritical carbon dioxide gas in the supercritical carbon dioxide gas supply circulation loop, so as to study the influence of the cooling gas flow rate on the cooling effect. In the present embodiment, the regulating valve 63 may be, for example, a solenoid valve, which automatically controls the flow rate of the fluid upon receiving a control signal.

[0067] In order to avoid unstable gas source pressure caused by the supercritical carbon dioxide supply device 61 directly supplying gas to the rotary cooling device, in the disclosed embodiment, the supercritical carbon dioxide gas supply circulation device is also provided with a storage tank 68, which is located between the water cooler 67 and the supercritical carbon dioxide supply device 61. The storage tank 68 is used to store the circulating gas source to provide a supercritical carbon dioxide gas source for the rotary cooling test. In addition, the storage tank 68 is also connected to the first vent valve (not shown in the figure), and when an emergency occurs, the pressure can be released through the first vent valve to enhance the safety of the storage of the supercritical carbon dioxide gas supply circulation device.

[0068] In the disclosed embodiment, the supercritical carbon dioxide turbine inter-shaft cooling test system further includes a second vent valve (not shown in the figure), which is connected to the rotary cooling device. When an emergency occurs or the test needs to be temporarily stopped, the cooling test system can be depressurized through the second vent valve to enhance the safety of the entire cooling test system.

[0069] The following will be combined Figure 1 The process of performing a rotation cooling test using the supercritical carbon dioxide turbine inter-shaft cooling test system according to an embodiment of the present disclosure is briefly described.

[0070] Specifically, the implementation of the rotary cooling test includes four stages: working fluid modulation stage, preparation stage, startup stage and test stage.

[0071] In the working medium modulation stage, the switching valve 65 is first switched to connect the inlet pipeline 611 with the bypass pipeline 613, and the connection between the supercritical carbon dioxide circulation loop and the rotary cooling device is disconnected, and the water cooler 67 is not started. Then, the supercritical carbon dioxide working medium required for the rotary cooling test is charged into the storage tank 68 from the supercritical carbon dioxide supply device 61, and the electric booster pump 62 and the electric heater 64 are started to increase the temperature and pressure of the supercritical carbon dioxide working medium in the circulation loop until the temperature and pressure required for the test are reached and maintained in a stable state, and the gas supply of the supercritical carbon dioxide supply device 61 is cut off, and the supercritical carbon dioxide reaching the temperature and pressure required for the test is stored in the storage tank 68.

[0072] In the preparation stage, the switching valve 65 cuts off the connection with the bypass line 613, connects the air inlet 321 and the exhaust port 323 of the cooling outer ring 32, starts the driving device, and accelerates the rotor 20 to a preset test speed.

[0073] In the startup phase, the storage tank 68 is used as the circulating gas source, and the supercritical carbon dioxide working medium returns to the storage tank 68 after passing through the electric booster pump 62, the regulating valve 63, the electric heater 64, the switching valve 65, the rotary cooling device, the check valve 66 and the water cooler 67. The electromagnetic heating device is started, the heating power is adjusted, the heating surface of the rotor 20 is quickly heated, and the temperature of the heating surface is kept stable.

[0074] During the test phase: after reaching the preset test conditions, the temperature of the surface of the rotor 20 is recorded in real time through the sealing and temperature measuring devices. By controlling the driving devices such as the motor 70, the regulating valve 63, the electric heater 64, the water cooler 67 and the electric booster pump 62, the speed, flow, temperature and pressure are adjusted respectively to realize the experimental test of rotary cooling under different working conditions.

[0075] In addition, when a serious failure or other emergency shutdown is required in the supercritical carbon dioxide turbine inter-shaft cooling test system, the electric heater 64, electromagnetic heating device and drive device are shut down, and the second vent valve (not shown) is opened to ensure safety.

[0076] In summary, the present disclosure provides a supercritical carbon dioxide turbine inter-shaft cooling test system, which can be used for the heat exchange performance test of the cantilever supercritical carbon dioxide turbine inter-shaft cooling structure. The supercritical carbon dioxide turbine inter-shaft cooling test system includes an electromagnetic heating device, a rotor, a rotary cooling device, a sealing and temperature measuring device, a drive transposition and a supercritical carbon dioxide gas supply circulation device, wherein the present disclosure can flexibly replace the inner ring to change the size of the test channel by designing a detachable rotary cooling device, thereby realizing the test implementation of a variety of channels with different geometric parameters; the shaft end dynamic seal is converted into a static seal through the isolation effect of the isolation plate, so that the rotary cooling system is completely closed, thereby achieving stable operation with zero leakage; in addition, a method for heating the rotor using the principle of electromagnetic induction is also provided, with fast heating speed and stable thermal boundary. In addition, the present disclosure can flexibly arrange the temperature measurement point positions and improve the temperature measurement accuracy by designing structures such as slip rings and micro-grooves.

[0077] The specific embodiments described above further illustrate the purpose, technical solutions and beneficial effects of the present disclosure. It should be understood that the above description is only a specific embodiment of the present disclosure and is not intended to limit the present disclosure. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present disclosure should be included in the protection scope of the present disclosure.

Claims

1. A supercritical carbon dioxide turbine inter-shaft cooling test system, characterized in that: include: A rotor, wherein micro grooves are symmetrically provided on the surface of the rotor in the axial direction, and a plurality of temperature measuring points are evenly distributed in the micro grooves; The rotary cooling device has openings at both ends, the rotor is inserted into the rotary cooling device to form a cooling cavity with the rotary cooling device; the rotary cooling device is provided with interfaces for supercritical carbon dioxide to enter and discharge in the circumferential direction; An electromagnetic heating device is detachably connected to one end of the rotary cooling device, wherein a heating cavity is provided on the inner surface of the electromagnetic heating device, and the head end of the rotor is close to the heating cavity; A sealing and temperature measuring device, electrically connected to the plurality of temperature measuring points; one end of the sealing and temperature measuring device is detachably connected to the other end of the rotary cooling device, and the other end cooperates with the tail end of the rotor to form a static seal; The sealing and temperature measuring device comprises a bearing seat, a slip ring and a magnetic coupling, wherein: The two ends of the bearing seat are detachably connected to the other end of the rotary cooling device and the magnetic coupling, respectively, and the magnetic coupling cooperates with the tail end of the rotor to form a static seal; The slip ring is installed between the front and rear bearings of the bearing seat, and is mounted on the rotor, and is electrically connected to the plurality of temperature measuring points; A plurality of cooling channels are provided in the bearing seat; The magnetic coupling consists of an inner magnet, an isolation plate and an outer magnet. The isolation plate is installed at the right end of the bearing seat. The inner magnet is arranged on the inner side of the isolation plate and is installed at the tail end of the rotor through a fixing part. The outer magnet is installed on the output shaft head of the driving device, and the driving device is fixed by a mounting seat.

2. The supercritical carbon dioxide turbine inter-shaft cooling test system according to claim 1, characterized in that: The rotary cooling device comprises a cooling inner ring and a cooling outer ring nested on the cooling inner ring, the two ends of the cooling outer ring are detachably connected to the electromagnetic heating device, the sealing and temperature measuring device, the rotor is inserted into the rotary cooling device and forms the cooling cavity with the cooling inner ring; the cooling outer ring is provided with a plurality of air inlets and exhaust ports along the circumferential direction to form an external interface of the rotary cooling device; The inner surface of the cooling inner ring is provided with an air inlet cavity and an exhaust cavity, and a plurality of air holes are evenly distributed in the circumference of the air inlet cavity and the exhaust cavity of the cooling inner ring to form an inlet and an outlet of the cooling cavity, and the inlet and the outlet of the cooling cavity are respectively connected to the air inlet and the exhaust port of the cooling outer ring.

3. The supercritical carbon dioxide turbine inter-shaft cooling test system according to claim 2, characterized in that: A diverter channel is provided in the cooling outer ring, one end of the diverter channel is communicated with the inlet of the cooling cavity, and the other end of the diverter channel is communicated with the air inlet of the cooling outer ring.

4. The supercritical carbon dioxide turbine inter-shaft cooling test system according to claim 1, characterized in that: The supercritical carbon dioxide turbine inter-shaft cooling test system also includes a supercritical carbon dioxide gas supply circulation device, which is respectively connected to the interfaces for supercritical carbon dioxide to enter and discharge on the rotary cooling device, so as to realize the circulation of supercritical carbon dioxide through the cooling cavity and cool the rotor.

5. The supercritical carbon dioxide turbine inter-shaft cooling test system according to claim 4, characterized in that: The supercritical carbon dioxide gas supply circulation device comprises a supercritical carbon dioxide supply device, an electric booster pump, an electric heater, a switching valve, a check valve, a water cooler, an inlet pipeline, a discharge pipeline and a bypass pipeline; wherein: On the inlet pipeline, the electric booster pump, the electric heater and the switching valve are sequentially connected in series along the direction in which the supercritical carbon dioxide moves; On the discharge pipeline, the check valve and the water cooler are connected in series in sequence along the direction in which the supercritical carbon dioxide moves; Wherein, the interfaces for supercritical carbon dioxide to enter and to be discharged on the rotary cooling device are respectively connected to the output end of the switching valve and the input end of the check valve; The bypass pipeline is communicated with the output end of the switching valve and the input end of the check valve respectively.

6. The supercritical carbon dioxide turbine inter-shaft cooling test system according to claim 5, characterized in that: The supercritical carbon dioxide gas supply circulation device also includes a regulating valve, which is arranged between the electric booster pump and the electric heater.

7. The supercritical carbon dioxide turbine inter-shaft cooling test system according to claim 5, characterized in that: The supercritical carbon dioxide gas supply circulation device further includes a storage tank disposed between the water cooler and the supercritical carbon dioxide supply device, wherein the storage tank is communicated with a first vent valve.

8. The supercritical carbon dioxide turbine inter-shaft cooling test system according to claim 1, characterized in that: The supercritical carbon dioxide turbine inter-shaft cooling test system further includes a second vent valve, which is connected to the rotary cooling device.

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