Experimental equipment for heterogeneous unbalanced condensation and liquefaction of hydrogen

Abstract

The utility model discloses experimental equipment for hydrogen heterogeneous unbalanced condensation and liquefaction, and solves the technical problem that the liquid hydrogen yield cannot be effectively improved as the structure of a hydrogen heterogeneous unbalanced condensation and hydrogen supersonic liquefaction expansion machine cannot be explored in the prior art. The experimental equipment comprises a hydrogen supply unit, a pre-cooling unit, a heterogeneous particle adding unit and a spray pipe for simulating a hydrogen supersonic liquefaction expansion machine which are sequentially connected, the gas outlet side of the spray pipe is connected with a circulating unit, and the liquid outlet side of the spray pipe is sequentially connected with a measuring unit, a centrifugal separator and a collecting unit. The heterogeneous particle adding unit is used for adding solid particles into precooled hydrogen, the spraying pipe is used for simulating heterogeneous unbalanced condensation of the hydrogen, the humidity in the spraying pipe is measured through the optical measuring module, the hydrogen liquefaction efficiency is measured, and the liquid hydrogen yield is increased; the number and the radius of the added solid particles are regulated and controlled, and simulation verification is combined, so that the hydrogen supersonic liquefaction expansion machine is guided to improve the liquid hydrogen yield.

Description

Technical Field

[0001] The utility model relates to the technical field of hydrogen liquefaction, in particular to experimental equipment for hydrogen heterogeneous non-equilibrium condensation and liquefaction. Background Art

[0002] Hydrogen liquefaction methods mainly rely on various refrigeration cycles, mainly focusing on the equilibrium liquefaction process induced by physical cooling and expansion. High energy consumption, high cost and complex equipment are the problems that need to be solved in the current development of hydrogen liquefaction technology.

[0003] Compared with the traditional hydrogen liquefaction method, the Chinese invention patent with an application publication date of 2021.11.26 and an application publication number of CN113701450 A discloses a hydrogen supersonic two-phase direct expansion liquefaction device, including a liquefaction pipeline and a precooling pipeline. The gaseous hydrogen in the liquefaction pipeline flows through the hydrogen compressor, the first heat exchanger to the first supersonic liquefaction expander in sequence. The liquid outlet side of the first supersonic liquefaction expander is connected to the liquid hydrogen storage tank, and the gas outlet side of the first supersonic liquefaction expander flows through the first heat exchanger and reaches the inlet side of the hydrogen compressor. The hydrogen is precooled by the first precooling pipeline and the second precooling pipeline, and the gaseous hydrogen in the liquefaction pipeline is quickly cooled. The supersonic liquefaction expander is used as an expansion refrigeration device, which has the advantages of safety, reliability, compact structure, and the ability to achieve two-phase expansion.

[0004] Supersonic liquefaction expanders can reduce the energy consumption of hydrogen liquefaction, but in long-term use, their liquefaction efficiency often fails to reach the ideal state due to factors such as fluid dynamics loss and friction loss. In order to achieve better liquefaction effect and increase the yield of liquid hydrogen, further research is needed on the liquefaction law of hydrogen. Utility Model Content

[0005] In view of the deficiencies in the above-mentioned background technology, the utility model proposes an experimental device for hydrogen heterogeneous non-equilibrium condensation and liquefaction. The problem to be solved is: the existing technology is unable to explore the structure of hydrogen heterogeneous non-equilibrium condensation and hydrogen supersonic liquefaction expansion machine, and thus cannot effectively improve the technical problem of liquid hydrogen yield.

[0006] The technical solution of this application is:

[0007] The experimental equipment for hydrogen heterogeneous non-equilibrium condensation and liquefaction comprises a hydrogen supply unit, a precooling unit, a heterogeneous particle adding unit and a nozzle simulating a hydrogen supersonic liquefaction expander which are connected in sequence, the gas outlet side of the nozzle is connected to a circulation unit, the liquid outlet side of the nozzle is connected to a measuring unit, a centrifugal separator and a collecting unit in sequence, the heterogeneous particle adding unit comprises a solid particle storage tank, a flow valve and a premixing chamber which are connected in sequence, the inlet of the premixing chamber is respectively connected to the precooling unit and the flow valve, the outlet of the premixing chamber is connected to the gas inlet side of the nozzle, the cross section of the nozzle is rectangular, and light-transmitting panels connected to the measuring unit are arranged on the left and right sides of the nozzle along the hydrogen flow direction.

[0008] The hydrogen supply unit and precooling unit of the technical solution can provide hydrogen and compress and cool the hydrogen. The heterogeneous particle adding unit is used to add solid particles to the flowing hydrogen. The added solid particles can be of different numbers and sizes. The nozzle is used to simulate the hydrogen supersonic liquefaction expander. The hydrogen undergoes volume compression and expansion in the nozzle. During the volume change process, the hydrogen will undergo heterogeneous non-equilibrium condensation with the solid particles as the condensation core, generating condensed droplets attached to the surface of the solid particles. The condensed droplets are liquid hydrogen. The air intake, liquid discharge and air discharge methods of the nozzle are the same as those of the hydrogen supersonic liquefaction expander. A valve 2 is provided between the heterogeneous particle adding unit and the precooling unit. The test unit and the collection unit are sequentially arranged along the flow direction of the hydrogen. The measuring unit can perform humidity test on the liquid hydrogen in the nozzle. The higher the humidity, the higher the liquefaction efficiency of the hydrogen and the higher the yield of liquid hydrogen. The nozzle includes a contraction section and an expansion section, and the expansion section to the outlet are all the liquid outlet side. A vortex generator similar to the hydrogen supersonic liquefaction expander is arranged on the air inlet side of the nozzle. Hydrogen, liquid hydrogen and solid particles are separated by centrifugal force and collected separately. Liquid hydrogen and solid particles flow to the end of the liquid outlet side of the nozzle under the action of centrifugal force. After solid-liquid separation, liquid hydrogen is led out from the end of the liquid outlet side of the nozzle to the collecting unit for collection, and the solid particles are returned to the heterogeneous particle adding unit through the pipeline. Unliquefied hydrogen is led out from the air outlet side of the nozzle, and is recovered through the circulation unit and flows back into the precooling unit.

[0009] Furthermore, the solid particles in the solid particle storage tank flow into the premixing chamber through a flow valve, and enter the nozzle after being evenly mixed with the hydrogen in the premixing chamber. A valve three is provided between the premixing chamber and the nozzle. The flow valve can control the amount of solid particles entering the premixing chamber. There can be one or more solid particle storage tanks. The size of the added solid particles can be changed by replacing the solid particle storage tank connected to the flow valve.

[0010] Furthermore, the shape of the nozzle first contracts and then expands along the flow direction of hydrogen, which facilitates the hydrogen to reach a transcritical state, and then a heterogeneous non-equilibrium condensation process occurs. The upper and lower sides of the nozzle are arc panels that first contract and then expand. The upper and lower symmetrical arc panels and the light-transmitting panels on the left and right sides are sealed and connected to form a hydrogen channel that first contracts and then expands, leaving only the inlet and outlet at both ends for the hydrogen and solid particle mixture to flow in and out. End caps are set at both ends of the nozzle or directly connected to the main pipeline; the rectangular cross-section is convenient for manufacturing and also convenient for the nozzle to connect to the measurement unit. The light-transmitting panel can be applied to a variety of optical measurement modules.

[0011] Preferably, the solid outlet of the centrifuge is connected to the solid particle storage tank, and the liquid outlet of the centrifuge is connected to the collection unit. The centrifuge collects liquid hydrogen and solid particles through the liquid hydrogen pipeline and the solid particle pipeline respectively, the liquid hydrogen enters the collection unit through the liquid hydrogen pipeline, and the solid particles enter the solid particle storage tank through the solid particle pipeline.

[0012] Preferably, there are several solid particle storage tanks, one of which is connected to the inlet of the premixing chamber through a flow valve. The premixing chamber is provided with multiple inlets and one outlet, each solid particle storage tank stores different types of solid particles, the opening and closing of the flow valve controls the duration of solid particle addition, and further controls the amount of solid particles added, and according to experimental needs, the flow valves of multiple solid particle storage tanks are opened in sequence or simultaneously, the composition of the mixture of hydrogen and solid particles in the premixing chamber is changed, and the liquefaction efficiency of hydrogen in the nozzle is measured.

[0013] Preferably, the liquid outlet side of the nozzle includes overflow holes evenly spaced along the upper and lower side walls of the nozzle, and each overflow hole is connected to a collection unit. The liquid outlet side of the nozzle includes a nozzle and overflow holes located on the upper and lower side walls of the nozzle. The hydrogen and solid particle mixture flows along the nozzle after passing through the air inlet side. Due to the shape of the nozzle that first contracts and then expands, the volume of hydrogen is first compressed and then expanded. In this process, the hydrogen undergoes heterogeneous non-equilibrium condensation and liquefaction. The overflow hole is set at the end of the flow direction of the hydrogen and solid particle mixture, and the outlet direction of the overflow hole matches the centrifugal force direction. The sizes of the overflow holes are the same, and the outlet direction of the overflow hole simulates the liquid outlet side direction of the hydrogen supersonic liquefaction expander. The liquid hydrogen and solid particle mixture obtained by expansion and liquefaction in the nozzle flows to the centrifuge through the overflow hole.

[0014] Preferably, the measuring unit comprises a density measuring module and a humidity measuring module arranged on a sliding mechanism, the measuring direction of the density measuring module is perpendicular to the light-transmitting panel, and the sliding direction of the sliding mechanism is parallel to the nozzle. Specifically, the density measuring module adopts optical measurement, and measures the position, size and growth data of the condensed droplets by shear interference method. The humidity measuring module measures the diameter and number of the condensed droplets by extinction method, and the humidity measuring module is arranged between the density measuring module and the overflow hole of the nozzle. The humidity measuring module comprises an optical fiber and a laser emission box connected by electrical signals, and the optical fiber is slidably connected to the light-transmitting panels on the left and right sides of the nozzle by a sliding mechanism, and the position of the optical fiber should avoid interference with the laser optical path of the density measuring module. The humidity measurement measures the diameter and number of the condensed droplets by extinction method, and then converts them to obtain the humidity. The higher the humidity, the higher the heterogeneous non-condensation efficiency of hydrogen and the higher the liquid hydrogen yield. The number of solid particles added on the air inlet side of the nozzle and the size of other solid particles are changed in turn. In each test, the optical fiber is fixed at different positions of the nozzle for multiple measurements to obtain the hydrogen expansion conditions when the liquefaction efficiency is the highest.

[0015] Preferably, the density measurement module includes a laser transmitter, a laser attenuator, a beam expander, and a collimating lens connected in sequence to one side of the nozzle; a 50% beam splitter, a reflector, and a camera are connected in sequence to the other side of the nozzle, and the 50% beam splitter and the reflector are arranged in pairs. The laser emission direction is perpendicular to the flow direction of the mixture of hydrogen and solid particles in the nozzle. The module on the left side of the nozzle can emit a laser beam in a specific direction, and the module on the right side of the nozzle can record the laser imaging after the laser is reflected or refracted. The density measurement module records the change process of the refractive index in the nozzle in real time through the shearing interferometer method, obtains the density through conversion, and outputs a clear pattern at each moment for analyzing the starting position of condensation.

[0016] Preferably, the sliding mechanism includes a movable bracket slidably connected to the light-transmitting panel, and the humidity measuring module is fixedly connected to the movable bracket. The sliding mechanism includes a movable bracket and a transmission rod that are threaded together. The optical fiber of the humidity measuring module is connected to the movable bracket of the sliding mechanism. The transmission rod is fixedly connected to the top of the nozzle through a fixed frame. One end of the transmission rod is connected to a driving motor. One end of the movable bracket is provided with an internal thread that cooperates with the transmission rod, and the other end is provided with a connection hole that is symmetrical with respect to the nozzle and is plugged in with the optical fiber. The movable bracket can also be plugged in with the transmission rod, and the position of the movable bracket can be directly adjusted manually.

[0017] Preferably, the precooling unit includes a hydrogen pipeline, a first cooling medium pipeline and a second cooling medium pipeline, the hydrogen pipeline includes a first hydrogen compressor, a second heat exchanger, a third heat exchanger, a second hydrogen compressor and a temperature and pressure sensor, the first cooling medium pipeline includes a first cooling medium compressor, a second heat exchanger and a supersonic liquefaction expander, a third heat exchanger, and the second cooling medium pipeline includes a second heat exchanger. A second cooling medium is introduced into the second cooling medium pipeline, and a first cooling medium is introduced into the first cooling medium pipeline. The first cooling medium flows through the first cooling medium compressor and the second heat exchanger. The second cooling medium cools down the first cooling medium in the second heat exchanger. The first cooling medium after the first cooling continues to flow through the supersonic liquefaction expander for expansion and liquefaction. Hydrogen is introduced into the hydrogen pipeline. The hydrogen is compressed by the first hydrogen compressor, cooled by heat exchange with the second cooling medium in the second heat exchanger, cooled by heat exchange with the liquefied first cooling medium in the third heat exchanger, and compressed twice by the second hydrogen compressor. Whether the hydrogen reaches the target temperature and target pressure is monitored by a temperature and pressure sensor. If the target temperature and target pressure are reached, valve 2 is opened to allow the hydrogen to enter the nozzle through the air intake side. If the target temperature and target pressure are not reached, the hydrogen is compressed and cooled to the target temperature and target pressure by adjusting the parameters of the first hydrogen compressor and the second hydrogen compressor and replacing the first cooling medium and the second cooling medium.

[0018] Preferably, the second cooling medium pipeline includes a second heat exchanger and a first heat exchanger, and the hydrogen pipeline also includes a first heat exchanger connected between the first hydrogen compressor and the second heat exchanger. The first heat exchanger is added before the second heat exchanger, and the hydrogen is cooled by heat exchange three times through the first heat exchanger, the second heat exchanger, and the third heat exchanger in sequence, thereby enhancing the cooling effect of the hydrogen.

[0019] Preferably, the circulation unit comprises a hydrogen circulation pipeline and a valve 5, one end of the hydrogen circulation pipeline is connected to the outlet side of the nozzle, and the other end is connected to the first hydrogen compressor. A part of the precooled hydrogen expands and liquefies in the nozzle to become liquid hydrogen, and the unliquefied hydrogen is discharged through the outlet side of the nozzle or flows into the hydrogen circulation pipeline, re-enters the precooling unit and the nozzle, and is re-precooled and liquefied.

[0020] Compared with the prior art, the technical solution disclosed in the utility model has the following beneficial effects:

[0021] 1. The nozzle is used to simulate the hydrogen supersonic liquefaction expander to simulate the non-equilibrium condensation and liquefaction phenomenon of hydrogen. The humidity in the nozzle is measured by the optical measurement module, which realizes the measurement of hydrogen liquefaction phenomenon and hydrogen liquefaction efficiency, filling the gap in the existing technology of the lack of hydrogen supersonic liquefaction expander for hydrogen liquefaction experimental equipment;

[0022] 2. Use a heterogeneous particle adding unit to add solid particles to the pre-cooled hydrogen, so that the hydrogen undergoes heterogeneous non-equilibrium condensation in the nozzle. Compared with the prior art that directly expands and liquefies the hydrogen, this enhances the liquefaction effect and helps improve the yield of liquid hydrogen;

[0023] 3. By regulating the solid particle storage tank and the flow valve to control the number of solid particles added to the nozzle and the radius of the solid particles, the liquid hydrogen yield of the nozzle is optimized. The relationship between the number of solid particles, the radius of the solid particles, the longitudinal section of the nozzle and the hydrogen liquefaction efficiency is verified by simulation. This can guide the addition of a specific number and size of solid particles to the hydrogen supersonic liquefaction expander to improve the liquid hydrogen yield. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the embodiments of the present utility model, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0025] Figure 1 It is the working principle diagram of the test equipment of the utility model;

[0026] Figure 2 This is a working principle diagram of the precooling module of the utility model;

[0027] Figure 3 This is a schematic diagram of the liquid hydrogen density measurement of the utility model;

[0028] Figure 4 This is a schematic diagram of the liquid hydrogen yield measurement of the utility model;

[0029] Figure 5 It is a structural schematic diagram of the nozzle of the utility model;

[0030] Figure 6 is a schematic diagram of the longitudinal section structure of a nozzle embodiment;

[0031] Figure 7 is the relationship between the nozzle longitudinal section and the liquid hydrogen yield when adding different numbers of nanometers;

[0032] Figure 8 It is a graph showing the relationship between the number of nanoparticles added and the liquid hydrogen yield.

[0033] Description of Figure Numbers:

[0034] 1 hydrogen supply unit, 2 valve one, 3 precooling unit, 301 first cooling medium compressor, 302 first hydrogen compressor, 303 supersonic liquefaction expander, 304 second hydrogen compressor, 305 first heat exchanger, 306 second heat exchanger, 307 third heat exchanger, 308 temperature and pressure sensor, 4 valve two, 5 premixing chamber, 6 flow valve, 7 solid particle storage tank, 8 valve three, 9 nozzle, 901 light-transmitting panel, 10 measuring unit, 1001 laser transmitter, 1002 laser attenuator, 1003 beam expander, 1004 collimating lens, 1005 50% beam splitter, 1006 reflector, 1007 camera, 1008 fixed frame, 1009 transmission rod, 1010 movable bracket, 1011 optical fiber, 11 centrifugal separator, 12 valve four, 13 collecting unit, 14 valve five. DETAILED DESCRIPTION

[0035] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the core concept of the utility model and the following embodiments, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0036] Example 1, experimental equipment for heterogeneous non-equilibrium condensation and liquefaction of hydrogen, such as Figure 1 As shown, it includes a hydrogen supply unit 1, a precooling unit 3, a heterogeneous particle adding unit and a nozzle 9 for simulating a hydrogen supersonic liquefaction expander connected in sequence, the gas outlet side of the nozzle 9 is connected to the circulation unit, and the liquid outlet side of the nozzle 9 is connected to the measuring unit 10, the centrifugal separator 11 and the collecting unit 13 in sequence, the heterogeneous particle adding unit includes a solid particle storage tank 7, a flow valve 6, and a premixing chamber 5 connected in sequence, the inlet of the premixing chamber 5 is respectively connected to the precooling unit 3 and the flow valve 6, and the outlet of the premixing chamber 5 is connected to the gas inlet side of the nozzle 9, the cross-section of the nozzle 9 is rectangular, and the left and right sides of the nozzle 9 are provided with light-transmitting panels 901 connected to the measuring unit 10 along the hydrogen flow direction.

[0037] Specifically, the hydrogen supply unit 1 and the precooling unit 3 can provide hydrogen and compress and cool the hydrogen. A valve 2 is provided between the hydrogen supply unit 1 and the precooling unit 3. The heterogeneous particle adding unit is used to add solid particles to the flowing hydrogen. The nozzle 9 is used to simulate the hydrogen supersonic liquefaction expander to expand and liquefy the mixture of hydrogen and solid particles reaching the target temperature and target pressure to obtain liquid hydrogen. The air intake mode, liquid outlet mode, and air outlet mode of the nozzle 9 are the same as those of the hydrogen supersonic liquefaction expander. A valve 2 4 is provided between the heterogeneous particle adding unit and the precooling unit 3. A valve 3 8 is provided between the heterogeneous particle adding unit and the air intake side of the nozzle 9. The measuring unit 10 and the collecting unit 13 are sequentially arranged along the flow direction of the hydrogen. The measuring unit 10 can perform a humidity test on the liquid hydrogen in the nozzle 9. The higher the humidity, the higher the hydrogen liquefaction efficiency and the higher the liquid hydrogen yield. The nozzle 5 includes a contraction section and an expansion section, and the expansion section to the outlet are both liquid outlet sides. A vortex generator identical to the hydrogen supersonic liquefaction expander is arranged on the air inlet side of the nozzle 5. Hydrogen, liquid hydrogen and solid particles are separated by centrifugal force and then collected separately. Liquid hydrogen and solid particles flow to the overflow hole of the nozzle 9 under the action of centrifugal force in the nozzle 9, and then pass through the centrifuge 11 for solid-liquid separation. Liquid hydrogen flows from the overflow hole of the nozzle 9 to the collection unit 13 for collection. The solid particles are returned to the heterogeneous particle adding unit through the pipeline or are directly discharged. Unliquefied hydrogen is directly discharged from the air outlet side of the nozzle 9, or is led to the circulation unit for recovery and then flows into the precooling unit 3 again.

[0038] like Figure 1 As shown, the solid particles in the solid particle storage tank 7 flow into the premixing chamber 5 through the flow valve 6, and enter the nozzle 9 after being evenly mixed with the hydrogen in the premixing chamber 5. A valve 3 8 is provided between the premixing chamber 5 and the nozzle 9. The flow valve 6 can control the amount of solid particles entering the premixing chamber 5. There can be one or more solid particle storage tanks 7. By replacing the solid particle storage tanks 7 connected to the flow valve 6, the size of the added solid particles can be changed.

[0039] like Figure 5As shown, in order to facilitate the display of the contraction and expansion structure, the expansion area at both ends of the nozzle 5 is specially enlarged and displayed. The shape of the nozzle 9 first contracts and then expands along the flow direction of hydrogen, which is convenient for hydrogen to reach a transcritical state, and then a heterogeneous non-equilibrium condensation process occurs. The nozzle 9 should be a cylindrical shape with a smooth and frictionless interior. The upper and lower sides of the nozzle 9 are arc panels that first contract and then expand. The upper and lower symmetrical arc panels and the light-transmitting panels 501 on the left and right sides are sealed and connected to form a hydrogen channel that first contracts and then expands, leaving only the inlet and outlet at both ends for the hydrogen and solid particle mixture to flow in and out. The connection method can be welding or connecting or bonding through bracket bolts. As long as the connection is leak-proof, end caps can be set at both ends of the nozzle 9 or directly connected to the main pipeline; the rectangular cross-section is convenient for production and also convenient for the nozzle 9 to connect the measurement unit 10. The light-transmitting panel 901 can be applied to a variety of optical measurement modules. The light-transmitting panel 901 is set on the left and right to facilitate the connection of the measurement unit 10. Preferably, the light-transmitting panel 901 is made of colorless and transparent tempered glass, and the upper and lower side surfaces of the nozzle 9 can be made of colorless and transparent tempered glass, or can be made of smooth and frictionless metal.

[0040] To facilitate experimental operation, the hydrogen supply unit 1 is a hydrogen storage tank, the precooling unit 3 uses a cooling medium to cool the hydrogen by heat exchange, the heterogeneous particle addition unit uses a solid particle injection pump or a solid particle storage tank 7 plus a flow valve 6, the nozzle 9 is made of transparent material, the measuring unit 10 uses an optical measurement module, and the collecting unit 13 is a liquid hydrogen storage tank.

[0041] Example 2, based on Example 1, an experimental device for heterogeneous non-equilibrium condensation and liquefaction of hydrogen, such as Figure 1 As shown, the solid outlet of the centrifuge 11 is connected to the solid particle storage tank 7, and the liquid outlet of the centrifuge 11 is connected to the collection unit 13. The centrifuge 11 collects liquid hydrogen and solid particles through the liquid hydrogen pipeline and the solid particle pipeline respectively. The solid particles enter the solid particle storage tank 7 through the solid particle pipeline, and the liquid hydrogen enters the collection unit 13 through the liquid hydrogen pipeline. A valve 12 is provided between the collection unit 13. To facilitate experimental operation, the collection unit 13 is a liquid hydrogen storage tank.

[0042] Embodiment 3, based on Embodiment 2, an experimental device for heterogeneous non-equilibrium condensation and liquefaction of hydrogen is provided, wherein a plurality of solid particle storage tanks 7 are provided, and one solid particle storage tank 7 is connected to the inlet of the premixing chamber 5 through a flow valve 6. The premixing chamber 5 is provided with a plurality of inlets and an outlet, and each solid particle storage tank 7 stores different kinds of solid particles. The opening and closing of the flow valve 6 controls the duration of solid particle addition, thereby controlling the amount of solid particles added. According to experimental needs, the flow valves 6 of a plurality of solid particle storage tanks 7 are opened in sequence or simultaneously, the composition of the mixture of hydrogen and solid particles in the premixing chamber 5 is changed, and the liquefaction efficiency of hydrogen in the nozzle 9 is measured. Preferably, the premixing chamber 5 is a box body provided with spiral stirring blades along the flow direction of hydrogen, and the hydrogen is fully mixed with the solid particles in the premixing chamber 5 during the flow along the stirring blades.

[0043] Embodiment 4, based on Embodiment 1, an experimental device for heterogeneous non-equilibrium condensation and liquefaction of hydrogen, the liquid outlet side of the nozzle 9 includes overflow holes evenly spaced along the upper and lower side walls of the nozzle 9, and each overflow hole is connected to the collection unit 13. The liquid outlet side of the nozzle 9 includes the nozzle 9 and the overflow holes located on the upper and lower side walls of the nozzle 9. The hydrogen and solid particle mixture flows along the nozzle 9 after passing through the air inlet side. Due to the shape of the nozzle 5 that first contracts and then expands, the volume of hydrogen is first compressed and then expanded. In this process, the hydrogen takes the solid particles as the condensation core, and heterogeneous non-equilibrium condensation and liquefaction occurs. The liquid hydrogen and solid particle mixture flows out along the overflow holes on the upper and lower side walls of the nozzle 9 under the action of flow velocity and centrifugal force. The overflow hole is set at the end of the flow direction of the hydrogen and solid particle mixture, and the outlet direction of the overflow hole matches the centrifugal flow direction of the liquid hydrogen and solid particle mixture. The liquid hydrogen and solid particle mixture in the nozzle 9 flows to the collection unit 13 through the overflow hole. Preferably, the collecting unit 13 is a liquid hydrogen storage tank, the overflow holes are of the same size, and the outlet direction of the overflow holes simulates the liquid outlet direction of a hydrogen supersonic liquefaction expander.

[0044] Example 5, based on Example 1, an experimental device for heterogeneous non-equilibrium condensation and liquefaction of hydrogen is provided, such as Figure 3-Figure 4As shown, the measuring unit 10 includes a density measuring module and a humidity measuring module arranged on a sliding mechanism. The measuring direction of the density measuring module is perpendicular to the light-transmitting panel 901, and the sliding direction of the sliding mechanism is parallel to the nozzle 9. The density measuring module adopts optical measurement, and measures the position, size and growth data of the heterogeneous condensation droplets of hydrogen by shear interference method. The laser of the density measuring module vertically passes through the light-transmitting panel 901, which is convenient for measuring and recording the hydrogen in the entire nozzle 9. When condensation droplets of hydrogen appear, the optical signal of the laser passing through the condensation droplets will change. The humidity measuring module measures the diameter and number of condensation droplets by extinction method. The humidity measuring module is arranged between the density measuring module and the overflow hole of the nozzle 9. The humidity measuring module includes an optical fiber 1011 and a laser emission box connected by electrical signals. The optical fiber 1011 is slidably connected to the light-transmitting panels 901 on the left and right sides of the nozzle 9 by a sliding mechanism. The position of the optical fiber 1011 should avoid interference with the laser optical path of the density measuring module. Humidity measurement uses the extinction method to measure the diameter and number of condensed droplets, which are then converted into humidity. The number and size of solid particles on the air inlet side of the nozzle 9 are changed in turn. In each test, the optical fiber 1011 is fixed at different positions of the nozzle 9 for multiple measurements to obtain the hydrogen expansion conditions when the liquefaction efficiency is highest.

[0045] Example 6, based on Example 5, an experimental device for heterogeneous non-equilibrium condensation and liquefaction of hydrogen, such as Figure 3 As shown, the density measurement module includes a laser emitter 1001, a laser attenuator 1002, a beam expander 1003, and a collimating lens 1004 connected in sequence to one side of the nozzle; a 50% beam splitter 1005, a reflector 1006, and a camera 1007 are connected in sequence to the other side of the nozzle, and the 50% beam splitter and the reflector are arranged in pairs. The laser emission direction is perpendicular to the flow direction of the hydrogen and solid particle mixture in the nozzle 9. The module on the left side of the nozzle 9 can emit a laser beam in a specific direction, and the module on the right side of the nozzle 9 can record the laser imaging after the laser is reflected or refracted. The density measurement module records the change process of the refractive index in the nozzle 9 in real time through the shearing interferometer method, obtains the density through conversion, and outputs a clear pattern at each moment for analyzing the starting position of condensation.

[0046] Example 7, based on Example 5, an experimental device for heterogeneous non-equilibrium condensation and liquefaction of hydrogen, such as Figure 4As shown, the sliding mechanism includes a movable bracket 1010 that is slidably connected to the light-transmitting panel 901, and the humidity measurement module is fixedly connected to the movable bracket 1010. The sliding mechanism includes a threaded movable bracket 1010 and a transmission rod 1009, and the optical fiber 1011 of the humidity measurement module is connected to the movable bracket 1010 of the sliding mechanism. The transmission rod 1009 is fixedly connected to the top of the nozzle 9 through a fixed frame 1008. One end of the transmission rod 1009 is connected to a driving motor. One end of the movable bracket 1010 is provided with an internal thread that matches the transmission rod 1009, and the other end is provided with a connection hole that is symmetrical with respect to the nozzle 9 and is plugged and matched with the optical fiber 1011. The movable bracket 1010 can also be plugged with the transmission rod 1009, and the position of the movable bracket 1010 can be directly adjusted manually.

[0047] Example 8, based on Example 1, an experimental device for heterogeneous non-equilibrium condensation and liquefaction of hydrogen is provided, such as Figure 2 As shown, the precooling unit 3 includes a hydrogen pipeline, a first cooling medium pipeline and a second cooling medium pipeline. The hydrogen pipeline includes a first hydrogen compressor 302, a second heat exchanger 306, a third heat exchanger 307, a second hydrogen compressor 304 and a temperature and pressure sensor 308. The first cooling medium pipeline includes a first cooling medium compressor 301, a second heat exchanger 306 and a supersonic liquefaction expander 303, a third heat exchanger 307, and the second cooling medium pipeline includes a second heat exchanger 306.

[0048] During precooling, the second cooling medium is introduced into the second cooling medium pipeline, the first cooling medium is introduced into the first cooling medium pipeline, the first cooling medium flows through the first cooling medium compressor 301 and the second heat exchanger 306, the second cooling medium cools the first cooling medium in the second heat exchanger 306, the first cooling medium after once cooling continues to flow through the supersonic liquefaction expander 303 for expansion and liquefaction, hydrogen is introduced into the hydrogen pipeline, the hydrogen is compressed by the first hydrogen compressor 302, exchanged with the second cooling medium in the second heat exchanger 306, and the first cooling medium is cooled and cooled. Thermal cooling, heat exchange cooling with the liquefied first cooling medium in the third heat exchanger 307, and then secondary compression by the second hydrogen compressor 304, and monitoring whether the hydrogen reaches the target temperature and target pressure through the temperature and pressure sensor 308. If the target temperature and target pressure are reached, open the valve 2 4 to allow the hydrogen to enter the premixing chamber 5. If the target temperature and target pressure are not reached, the hydrogen is compressed and cooled to the target temperature and target pressure by adjusting the parameters of the first hydrogen compressor 302 and the second hydrogen compressor 304, and replacing the first cooling medium and the second cooling medium.

[0049] Preferably, the first cooling medium and the second cooling medium are both inert gases, the first cooling medium is helium and the second cooling medium is nitrogen; the first cooling medium may also be nitrogen and the second cooling medium may be liquefied natural gas, as long as the liquefaction temperature of the first cooling medium is lower than the liquefaction temperature of the second cooling medium.

[0050] Example 9, based on Example 8, an experimental device for heterogeneous non-equilibrium condensation and liquefaction of hydrogen, such as Figure 2 As shown, the second cooling medium pipeline includes a second heat exchanger 306 and a first heat exchanger 305, and the hydrogen pipeline also includes a first heat exchanger 305 connected between the first hydrogen compressor 302 and the second heat exchanger 306. The first heat exchanger 305 is added before the second heat exchanger 306, and the hydrogen is cooled three times by heat exchange through the first heat exchanger 305, the second heat exchanger 306, and the third heat exchanger 307 in sequence. The first heat exchanger 305 and the second heat exchanger 306 are both auxiliary cooling, and the third heat exchanger 307 is the main cooling process. The three coolings enhance the cooling effect of the hydrogen.

[0051] Example 10, based on Example 8, an experimental device for heterogeneous non-equilibrium condensation and liquefaction of hydrogen, such as Figure 1 As shown, the circulation unit includes a hydrogen circulation pipeline and a valve 5 14, one end of the hydrogen circulation pipeline is connected to the outlet side of the nozzle 9, and the other end is connected to the first hydrogen compressor 302. A part of the precooled hydrogen expands and liquefies in the nozzle 9 to become liquid hydrogen, and the unliquefied hydrogen is directly discharged through the outlet side of the nozzle 9, or flows into the hydrogen circulation pipeline, re-enters the precooling unit 3 and the nozzle 9, and is re-compressed, precooled and liquefied. Based on the upward flow of hydrogen, the hydrogen circulation pipeline is arranged above the outlet side of the nozzle 9.

[0052] When implementing Example 10, the hydrogen liquefaction efficiency is measured by using experimental equipment and combined with simulation analysis and verification. The experimental and verification methods are as follows:

[0053] The first step: close the valve 2 4 controlling the connection between the precooling unit 3 and the premixing chamber 5, open the valve 2 controlling the switch of the hydrogen storage tank 1, so that hydrogen enters the hydrogen pipeline of the precooling unit 3, passes the second cooling medium of the second cooling medium pipeline into the second heat exchanger 306, and passes the first cooling medium of the first cooling medium pipeline into the first cooling medium compressor 301;

[0054] Step 2: Use the temperature and pressure sensor 308 to determine whether the temperature and pressure of the hydrogen after secondary compression have reached the required target critical conditions, open the valve 2 4 and the flow valve 6, and allow the hydrogen and solid particles that have reached the target pressure and target temperature to enter the premixing chamber 5 and be fully mixed;

[0055] Step 3: by adjusting the flow valve 6 to change the number of solid particles entering the premixing chamber 5 and the radius of the solid particles, the valve 3 8 is opened to measure the density of liquid hydrogen and the hydrogen liquefaction efficiency in the nozzle 9, and the hydrogen liquefaction efficiency when different numbers of solid particles and radii of solid particles are added is measured respectively;

[0056] Step 4: Construct a simulation model according to the radius of the solid particles, the number of solid particles, the hydrogen temperature, the hydrogen pressure and the structural parameters of the nozzle 9 set each time, and simulate and verify the liquid hydrogen yield in each area of ​​the nozzle 9 according to the radius of the solid particles and the number of solid particles controlled by the experimental equipment, and obtain the relationship between the radius of the solid particles, the number of solid particles, the structure of the nozzle 9 and the liquid hydrogen yield, so as to guide the addition of a specific number and size of solid particles to the hydrogen supersonic liquefaction expander to improve the hydrogen liquefaction efficiency.

[0057] like Figure 6-Figure 8 As shown, Figure 6 To construct the simulation model of the nozzle 9, the nozzle 9 uses the front section l 1 Compress the hydrogen and use the rear section l 2 The expansion of hydrogen, Figure 7 It is a simulation diagram of liquid hydrogen yield. It can be seen that under the conditions of not changing the nozzle 9, hydrogen pressure and hydrogen temperature, and the size of the added solid particles, the amount of solid particles added changes, and the liquid hydrogen yield changes along the hydrogen flow direction in the nozzle 9. Figure 8 It is a dot graph of liquid hydrogen yield and the number of solid particles added. It can be seen that the liquid hydrogen yield of nozzle 9 at x=0.06m is the highest, and when the number of solid particles added is Number 4, the liquid hydrogen yield is the highest. Therefore, the liquid hydrogen yield can be improved by controlling the number and size of solid particles to guide the hydrogen supersonic liquefaction expander.

[0058] The parts not described in detail in the present invention are all conventional technical means known to those skilled in the art.

[0059] The above content shows and describes the basic principle, main features and beneficial effects of the utility model. The above description is only a preferred embodiment of the utility model and is not intended to limit the utility model. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the utility model shall be included in the protection scope of the utility model.

Claims

1. Experimental equipment for heterogeneous non-equilibrium condensation and liquefaction of hydrogen, characterized by: The invention comprises a hydrogen supply unit (1), a precooling unit (3), a heterogeneous particle addition unit and a nozzle (9) simulating a hydrogen supersonic liquefaction expander connected in sequence, wherein the gas outlet side of the nozzle (9) is connected to a circulation unit, and the liquid outlet side of the nozzle (9) is connected to a measuring unit (10), a centrifugal separator (11) and a collecting unit (13) in sequence, wherein the heterogeneous particle addition unit comprises a solid particle storage tank (7), a flow valve (6) and a premixing chamber (5) connected in sequence, wherein the inlet of the premixing chamber (5) is respectively connected to the precooling unit (3) and the flow valve (6), and the outlet of the premixing chamber (5) is connected to the gas inlet side of the nozzle (9), wherein the cross section of the nozzle (9) is rectangular, and light-transmitting panels (901) connected to the measuring unit (10) are arranged on the left and right sides of the nozzle (9) along the hydrogen flow direction.

2. The experimental equipment for heterogeneous non-equilibrium condensation and liquefaction of hydrogen according to claim 1, characterized in that: The solid outlet of the centrifuge (11) is connected to the solid particle storage tank (7), and the liquid outlet of the centrifuge (11) is connected to the collection unit (13).

3. The experimental equipment for heterogeneous non-equilibrium condensation and liquefaction of hydrogen according to claim 2, characterized in that: A plurality of solid particle storage tanks (7) are provided, and one solid particle storage tank (7) is connected to the inlet of the premixing chamber (5) via a flow valve (6).

4. The experimental equipment for heterogeneous non-equilibrium condensation and liquefaction of hydrogen according to claim 1, characterized in that: The liquid outlet side of the nozzle (9) comprises overflow holes evenly spaced along the upper and lower side walls of the nozzle (9), and each overflow hole is connected to a collection unit (13).

5. The experimental equipment for heterogeneous non-equilibrium condensation and liquefaction of hydrogen according to claim 1, characterized in that: The measuring unit (10) comprises a density measuring module and a humidity measuring module arranged on a sliding mechanism, the measuring direction of the density measuring module is perpendicular to the light-transmitting panel (901), and the sliding direction of the sliding mechanism is parallel to the nozzle (9).

6. The experimental device for heterogeneous non-equilibrium condensation and liquefaction of hydrogen according to claim 5, characterized in that: The density measurement module comprises a laser emitter (1001), a laser attenuator (1002), a beam expander (1003), and a collimating lens (1004) which are sequentially connected to one side of the nozzle (9); a 50% beam splitter (1005), a reflector (1006), and a camera (1007) are sequentially connected to the other side of the nozzle (9); the 50% beam splitter (1005) and the reflector (1006) are arranged in pairs.

7. The experimental equipment for heterogeneous non-equilibrium condensation and liquefaction of hydrogen according to claim 5, characterized in that: The sliding mechanism comprises a movable bracket (1010) slidably connected to the light-transmitting panel (901), and the humidity measurement module is fixedly connected to the movable bracket (1010).

8. The experimental equipment for heterogeneous non-equilibrium condensation and liquefaction of hydrogen according to claim 1, characterized in that: The precooling unit (3) comprises a hydrogen pipeline, a first cooling medium pipeline and a second cooling medium pipeline; the hydrogen pipeline comprises a first hydrogen compressor (302), a second heat exchanger (306), a third heat exchanger (307), a second hydrogen compressor (304) and a temperature and pressure sensor (308); the first cooling medium pipeline comprises a first cooling medium compressor (301), a second heat exchanger (306) and a supersonic liquefaction expander (303), and a third heat exchanger (307); and the second cooling medium pipeline comprises the second heat exchanger (306).

9. The experimental device for heterogeneous non-equilibrium condensation and liquefaction of hydrogen according to claim 8, characterized in that: The second cooling medium pipeline includes a second heat exchanger (306) and a first heat exchanger (305), and the hydrogen pipeline also includes a first heat exchanger (305) connected between the first hydrogen compressor (302) and the second heat exchanger (306).

10. The experimental equipment for heterogeneous non-equilibrium condensation and liquefaction of hydrogen according to claim 8, characterized in that: The circulation unit comprises a hydrogen circulation pipeline and a valve five (14), one end of the hydrogen circulation pipeline is connected to the gas outlet side of the nozzle (9), and the other end is connected to the first hydrogen compressor (302).

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