A gas-liquid two-phase visualization test system, safe operation method and data processing method

Abstract

The present invention belongs to the technical field of ion compressors, and in particular, relates to a gas-liquid two-phase visualization test system, a safe operation method, and a data processing method. A gas-liquid two-phase visualization test system includes an intake module, a cylinder simulation module, and an exhaust module connected in series in sequence. The cylinder simulation module includes two or more stages of visual piston units connected in series, and an interstage buffer for temporarily storing test gas is also provided on the pipeline between adjacent visual piston containers; a limit device is provided outside the straight pipeline directly connected to the visual piston container; the intake module generates test gas, and the test gas flows through the visual piston units connected in series in the cylinder simulation module in sequence, and the visual piston container in the visual piston unit performs a piston reciprocating motion to compress the test gas and then send it to the exhaust module, and the exhaust module discharges the compressed gas into the surrounding environment. The present invention can simulate and observe the complex gas-liquid flow field in the cylinder of the ion compressor in a realistic, efficient and safe manner.

Description

Technical Field

[0001] The present invention belongs to the technical field of ion compressors, and in particular relates to a gas-liquid two-phase visualization test system, a safe operation method and a data processing method. Background Art

[0002] At present, the main process flow adopted by domestic hydrogen refueling stations is based on the storage and transportation of high-pressure gaseous hydrogen, mainly using long-tube trailers outside the station to supply hydrogen. The long-tube trailer transports 20MPa compressed hydrogen from the hydrogen production unit to the fixed station, and the hydrogen is unloaded to the high-pressure hydrogen storage tank in the station through the compressor in the hydrogen refueling station. When the vehicle is refueled, the hydrogen output from the long-tube trailer or hydrogen storage tank is filled into the on-board hydrogen storage bottle of the fuel cell vehicle through the hydrogen filling machine. With the popularization of new energy vehicles and fuel cells, the demand for compressors, which are key core equipment of hydrogen refueling stations, is also increasing.

[0003] Reciprocating ion compressors fill a liquid with special physical and chemical properties, namely ionic liquid, into the cylinder and compress the gas under the drive of the hydraulic piston. Ionic liquid is almost incompressible, does not dissolve or pollute hydrogen, and has good lubrication and cooling properties. Ionic liquid is filled between hydrogen and the hydraulic piston, which solves the hydrogen sealing and hydrogen pollution problems of the hydraulic piston. At the same time, ion compressors do not have wearing parts such as piston rings and packings of piston compressors, have high operating frequency, and occupy a small area. The use of ion compressors can effectively improve compression efficiency and reduce energy consumption. There are very few types of ion compressors that have been launched, and these reciprocating ion compressors are not only costly, but also cannot meet the needs of consumers well due to the limited choices. Therefore, the current market for ion compressors is relatively blank and has huge potential. It is necessary to accelerate the research and development of reciprocating ion compressors.

[0004] However, the intermittent intake and exhaust of the reciprocating ion compressor will cause uneven changes in the internal pressure of the pipeline, resulting in pipeline vibration, a phenomenon known as air flow pulsation. The compressor contains multiple straight pipelines. If a large amount of air flow pulsation occurs in the straight pipeline, it will seriously affect the working efficiency and safety of the reciprocating ion compressor, and even affect the safety of the hydrogen storage container that is subsequently filled with compressed hydrogen.

[0005] The core of the research and development of reciprocating ion compressors is to simulate and observe the complex gas-liquid flow field in the cylinder of the reciprocating ion compressor (for ease of description, "simulating the complex gas-liquid flow field in the cylinder of the reciprocating ion compressor" is referred to as "test" below), so airflow pulsation may also occur in the straight pipeline during the test. If a large-scale airflow pulsation occurs during the test, it will not only affect the test efficiency, but severe airflow pulsation may also threaten the personal safety of the technicians on site. Therefore, how to conduct the test safely and efficiently has become a difficult problem to be solved in the research and development of reciprocating ion compressors. Summary of the invention

[0006] The purpose of the present invention is to overcome the deficiencies of the above-mentioned prior art and to provide a gas-liquid two-phase visualization test system, which can not only realistically and efficiently simulate and observe the complex gas-liquid flow field in the cylinder of an ion compressor, but also ensure the safety during the simulation and observation process, thereby facilitating the research and development of ion compressors and ionic liquids.

[0007] To achieve the above object, the present invention adopts the following technical solutions:

[0008] A gas-liquid two-phase visualization test system comprises an air intake module, a cylinder simulation module and an air outlet module which are connected in series in sequence, wherein the cylinder simulation module comprises two or more stages of visual piston units connected in series, each of which comprises a visual piston container and a one-way valve, wherein the one-way valve is arranged on the air outlet pipeline of the visual piston container, and the visual piston container is transparent and contains a test liquid; an interstage buffer for temporarily storing the test gas is also arranged on the pipeline between adjacent visual piston containers; a limit device is arranged outside the straight pipeline directly connected to the visual piston container; the air intake module generates test gas, and the test gas flows through the visual piston units connected in series in sequence in the cylinder simulation module, and the visual piston container in the visual piston unit performs a piston reciprocating motion to compress the test gas and then sends it to the air outlet module, and the air outlet module discharges the compressed gas into the surrounding environment.

[0009] Preferably, the gas outlet module includes a gas-liquid separator, a flow meter and a fourth valve which are connected in series in sequence along the test gas transmission direction, and the gas outlet of the fourth valve is connected to the surrounding environment, and the fourth valve controls the final pressure of the compressed gas.

[0010] Preferably, the visible piston container includes a sleeve, an upper cover, a base, a piston and an electric lift, the sleeve is transparent, the piston is arranged in the sleeve, the base is fixedly arranged at one end of the sleeve, the upper cover is detachably arranged at the other end of the sleeve, the base is sleeved on the electric lift, one end of the electric lift is fixedly connected to the lower surface of the piston, and the electric lift drives the piston to reciprocate in the sleeve along the length direction of the sleeve; when the upper cover is fixed to one end of the sleeve, the lower surface of the upper cover, the inner wall of the sleeve and the upper surface of the piston form a sealed space, and the test liquid is located in the sealed space; the upper cover is also provided with an air inlet and an air outlet; the operating states of the pistons in adjacent visible piston units are opposite; the upper cover is also provided with a temperature sensor and a pressure sensor.

[0011] Preferably, the inter-stage buffer part includes an exhaust buffer tank and an intake buffer tank, the exhaust buffer tank is arranged on the pipeline between the visible piston container and the one-way valve of the current visible piston unit, and the intake buffer tank is arranged on the pipeline between the one-way valve of the current visible piston unit and the visible piston container of the next-stage visible piston unit.

[0012] Preferably, the limiting device includes an elastic buffer layer and a rigid limiting layer, the elastic buffer layer is tightly wrapped on the outer wall of the linear pipeline, the inner wall of the rigid limiting layer is in contact with the outer wall of the elastic buffer layer, and the spatial position of the rigid limiting layer is fixed.

[0013] Preferably, it also includes an imaging module, which includes a camera and a parallel light source, the parallel light source is arranged opposite to the camera lens, the visible piston container is arranged on the light irradiation path between the parallel light source and the camera lens, and the camera is used to shoot the test liquid in the visible piston container.

[0014] Preferably, the air intake module comprises a gas source, a preheating device and a first valve which are connected in series along the test gas transmission direction.

[0015] The present invention also provides a safe operation method of a gas-liquid two-phase visualization test system, which is applied to a gas-liquid two-phase visualization test system as described above, and comprises the following steps:

[0016] S1, presetting various test parameters in a gas-liquid two-phase visualization test system according to the test conditions;

[0017] The test parameters include the type of test gas, the type of test liquid, the concentration of the test liquid, the set temperature of the preheating device, the initial thickness of the test liquid in the visual piston container, the outlet pressure of the first valve, the outlet pressure of the fourth valve, the movement speed of the electric lift, the specifications of the visual piston container, the top dead center position of the piston, and the duration of this test;

[0018] S2, fix the upper cover on the sleeve, open the first valve, the one-way valve and the fourth valve, start the electric lift, each electric lift drives the piston to reciprocate in the vertical direction, and the working conditions in the cylinder of the ion compressor can be simulated in the visible piston container to obtain the test data of the current test: each sensor and flow meter collect data, and the camera takes the gas-liquid flow field image in the visible piston container;

[0019] S3, when the current test is finished, a gas-liquid two-phase visualization test system is powered off, and the gas outlet module uses a gas-liquid separator to collect the test liquid in the gas outlet pipeline of the cylinder simulation module;

[0020] In S2, the exhaust buffer tank and the intake buffer tank reduce the speed and amplitude of the pipeline pressure change of the linear pipeline in the test system by storing and releasing the test gas, and the limit device limits the vibration amplitude of each linear pipeline.

[0021] The present invention also provides a data processing method for a gas-liquid flow field visualization test, which uses a safe operation method of a gas-liquid two-phase visualization test system as described above to obtain test data, including the following contents: a gas-liquid two-phase visualization test system includes a two-stage visual piston unit connected in series, and based on the temperature sensor data and pressure sensor data in the visual piston container, the compression efficiency of the two-stage visual piston container in series is calculated; at the same time, all gas-liquid flow field images in the current test are analyzed, and the total droplet sputtering intensity in each gas-liquid flow field image is calculated; and the total amount of test liquid in the gas-liquid separator after each test is recorded.

[0022] Preferably, the compression efficiency of the two-stage visible piston container connected in series is calculated, including the following specific contents:

[0023] At a certain moment, the temperature sensor value in the first-stage visual piston container is recorded as T1, the pressure sensor value is recorded as P1, the temperature sensor value in the second-stage visual piston container is recorded as T2, the pressure sensor value is recorded as P2, and the compression efficiency of the two-stage visual piston container in series is calculated. :

[0024] , where κ represents the polytropic index of the test gas;

[0025] The analysis of the gas-liquid flow field image includes the following specific contents:

[0026] Observe and record the fluctuation condition of the test liquid, the droplet splashing condition, the bubble content in the test liquid, and the degree of separation between the test liquid and the piston in the gas-liquid flow field image;

[0027] The fluctuation condition of the test liquid includes the peaks and valleys on the upper surface of the test liquid and the peaks and valleys on the lower surface of the test liquid;

[0028] The droplet splashing condition includes the splashing droplet angle, splashing droplet shape and splashing speed of the test liquid;

[0029] The separation degree between the test liquid and the piston refers to the maximum distance between the lower surface of the test liquid and the upper surface of the piston in the current gas-liquid flow field image;

[0030] Calculate the total droplet splash intensity in each gas-liquid flow field image, including the following details:

[0031] In the gas-liquid flow field image, the distance between the lower surface of the upper cover and the upper surface of the test liquid is recorded as L0. When there is fluctuation on the upper surface of the test liquid, L0 takes the arithmetic mean of the distance between the lower surface of the upper cover and the fluctuation surface of the test liquid;

[0032] There are n sputtering droplets in the current gas-liquid flow field image, and the vertical distance between the lower surface of the upper cover and the center of the i-th sputtering droplet in the current gas-liquid flow field image is recorded as L i , 1≤i≤n and i is a positive integer, then the sputtering intensity L of the i-th sputtering droplet in the current gas-liquid flow field image is d,i For L d,i =(L0-L i ) / L0; the total droplet sputtering intensity L in the current gas-liquid flow field image d,total : .

[0033] The beneficial effects of the present invention are:

[0034] (1) The gas-liquid two-phase visualization test system of the present invention can realistically, safely and efficiently simulate the working process of an ion compressor and a multi-stage ion compressor system, making it easy for technicians to efficiently conduct simulation tests and study the effects of changes in test parameters on the stability of the gas-liquid flow field in the cylinder of the ion compressor, the energy efficiency of the ion compressor, and the total amount of ion liquid carried out by the compressed gas.

[0035] (2) A gas-liquid two-phase visualization test system of the present invention can realistically simulate the multi-stage compression of the test gas by two or more series-connected ion compressors.

[0036] (3) In a gas-liquid two-phase visualization test system of the present invention, the upper cover of the visual piston container is detachable, which is convenient for technicians to flexibly load the test liquid into the visual piston container, or replace the test liquid, or adjust the total amount of the test liquid in the visual piston container according to the test content, thereby improving the test efficiency; at the same time, it is also convenient to clean the carbon deposits generated by the test liquid in the sleeve after multiple tests.

[0037] (4) The gas-liquid two-phase visualization test system of the present invention, in which the visual piston container cooperates with the parallel light source and high-speed camera in the imaging module, can obtain high-definition images of various details in the gas-liquid flow field during the test, making it easier for technicians to study the impact of changes in test parameters on the stability of the gas-liquid flow field in the cylinder of the ion compressor.

[0038] (5) The gas-liquid two-phase visualization test system of the present invention can greatly reduce the airflow pulsation occurring in the straight pipeline through the interstage buffer during the test, and cooperate with the limit device wrapped outside the straight pipeline to further reduce the vibration of the straight pipeline caused by the airflow pulsation, and limit the maximum vibration amplitude of the straight pipeline, thereby suppressing the large-scale vibration of the straight pipeline caused by the airflow pulsation from multiple dimensions, improving the test efficiency, extending the life of the straight pipeline in the test system, and avoiding threats to the personal safety of the on-site technicians; further ensuring the safe operation of the test system during the entire test process, and also ensuring the safe conduct of the test.

[0039] (6) The gas-liquid two-phase visualization test method of the present invention can simulate a real multi-stage ion compressor system by controlling the intake pressure of the first-stage visual piston container and controlling the final compressed gas pressure, and collect the gas pressure and temperature in each visual piston container through each temperature sensor and pressure sensor, and convert the pressure ratio distribution of each ion compressor in real time, which is helpful for optimizing the design of the multi-stage ion compressor system and improving the safety of the multi-stage ion compressor system.

[0040] (7) In a gas-liquid two-phase visualization test method of the present invention, the test liquid in the gas-liquid separator is recovered. On the one hand, it saves costs. On the other hand, it measures the total amount of test liquid brought out by the compressed gas in each test, which is used to guide the subsequent development of ionic liquids and calibrate the appropriate threshold values ​​of various test parameters in the ion compressor.

[0041] (8) The data processing method of the gas-liquid flow field visualization test of the present invention can obtain important data during the working process of the ion compressor, such as the volume of ion liquid brought out by the compressed gas, relevant data on the stability of the gas-liquid flow field, and the compression efficiency of the two-stage ion compressor. It will not only help technicians to formulate more accurate gas-liquid flow field stability judgment standards in the future and calibrate the maximum threshold of the total droplet sputtering intensity of the ion compressor, but also help to verify the safety of the multi-stage ion compressor system and guide technicians in the development of ion liquids, the design of ion compressors, the structural optimization of ion compressor systems, and the parameter calibration of the ion compressor for the optimal operating state. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 It is a schematic diagram of the overall structure of a gas-liquid two-phase visualization test system of the present invention;

[0043] Figure 2 It is a schematic diagram of the overall structure of the visual piston container of the present invention;

[0044] Figure 3 is a cross-sectional view of a visible piston container of the present invention;

[0045] Figure 4 It is a schematic diagram of the state of the test liquid when the visible piston container is exhausted during the test;

[0046] Figure 5 It is a schematic diagram of the state of the test liquid when the piston in the visible piston container moves to the top dead center during the test;

[0047] Figure 6 It is a schematic diagram of the state of the test liquid when air is sucked into the visual piston container during the test;

[0048] Figure 7 for Figure 1 Enlarged cross-sectional view at point A in the figure. DETAILED DESCRIPTION

[0049] In order to make the technical solution of the present invention clearer and more specific, the present invention is clearly and completely described below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. The solutions derived from equivalent replacements of the technical features of the technical solution of the present invention and conventional reasoning by ordinary technicians in this field without making any creative work all fall within the protection scope of the present invention.

[0050] When the ion compressor is working, there is ionic liquid and gas to be compressed in the cylinder. For the convenience of description, in a gas-liquid two-phase visualization test system of the present invention, the ionic liquid is recorded as the test liquid and the gas to be compressed is recorded as the test gas.

[0051] like Figure 1 As shown, a gas-liquid two-phase visualization test system is invented, including an air intake module, a cylinder simulation module, and an air outlet module which are connected in series along the test gas transmission direction. The cylinder simulation module is transparent and has a test liquid built in. After the test gas is generated in the air intake module, the test gas enters the cylinder simulation module. The piston in the cylinder simulation module reciprocates to compress the test gas, and then it flows through the air outlet module and is discharged into the surrounding environment.

[0052] The air intake module includes an air source 1, a preheating device 2 and a first valve V1 which are connected in series in sequence. The air source 1 is used to generate test gas. After the preheating device 2 is turned on, the test gas can be heated to a set temperature to increase the air intake temperature of the cylinder simulation module. The first valve V1 is used to control the air intake pressure of the cylinder simulation module.

[0053] In this embodiment, the first valve V1 is an electric valve.

[0054] Optionally, a third valve V3 for controlling whether the gas source 1 is to discharge gas is provided on the pipeline between the gas source 1 and the preheating device 2. In this embodiment, the third valve V3 is a solenoid valve.

[0055] The intake temperature of the cylinder simulation module of the present invention is adjustable, so that the test system of the present invention can not only simulate the operation of the ion compressor cylinder under normal temperature conditions in a low temperature environment; the test system of the present invention can also be used to study the influence of different intake temperatures on the ion compressor.

[0056] The cylinder simulation module includes more than one level of visible piston units connected in series, each of which includes a visible piston container 3 and a one-way valve VT. Each one-way valve VT is arranged on the outlet pipe of the corresponding visible piston container 3, so the number of one-way valves VT is equal to the number of visible piston containers 3, and the test liquid in the visible piston container 3 can be removed and replaced. One end of the first valve V1 is connected to the outlet pipe of the preheating device 2, and the other end is connected to the inlet pipe of the visible piston container 3 near the preheating device 2. During the test, the piston reciprocates in the visible piston container 3 to compress the test gas, simulating the working process in the cylinder of the ion compressor.

[0057] In this embodiment, the cylinder simulation module includes a two-stage visual piston unit, the visual piston container 3 close to the air intake module is recorded as the first-stage visual piston container, the one-way valve VT on the air outlet pipeline of the first-stage visual piston container is recorded as the first-stage one-way valve, the visual piston container 3 away from the air intake module is recorded as the second-stage visual piston container, and the one-way valve VT on the air outlet pipeline of the second-stage visual piston container is recorded as the second-stage one-way valve, then the first-stage visual piston container, the first-stage one-way valve, the second-stage visual piston container and the second-stage one-way valve are connected in series in sequence. The compressed gas discharged from the air outlet of the second-stage visual piston container is mixed with a small amount of test liquid, which is recorded as mixed gas.

[0058] Optionally, an interstage buffer portion is further provided between the three adjacent visible piston containers, and the interstage buffer portion includes an exhaust buffer tank 61 and an intake buffer tank 62. The exhaust buffer tank 61 is provided on the pipeline between the intake end of the first-stage one-way valve and the first-stage visible piston container, and the intake buffer tank 62 is provided on the pipeline between the outlet end of the first-stage one-way valve and the second-stage visible piston container.

[0059] The gas outlet module includes a gas-liquid separator 4, a flow meter 5 and a fourth valve V4 which are connected in series in the transmission direction of the test gas. The gas outlet end of the last-stage one-way valve is connected to the gas inlet pipeline of the gas-liquid separator 4. The gas outlet pipeline of the gas-liquid separator 4 is connected in series with a flow meter 5 and a fourth valve V4. The fourth valve V4 is used to control the pressure of the compressed gas, and the gas outlet of the fourth valve V4 is connected to the surrounding environment. The mixed gas discharged from the cylinder simulation module first passes through the gas-liquid separator 4 to separate the compressed gas from a small amount of test liquid. The compressed gas then flows through the flow meter 5 and the fourth valve V4 in sequence and is discharged into the surrounding environment.

[0060] In this embodiment, the fourth valve V4 is a back pressure valve.

[0061] Optionally, a second valve V2 is provided at the bottom of the gas-liquid separator 4. After the gas-liquid separator 4 separates the compressed gas from the test liquid in the mixed gas, the mixed gas flows out from the gas outlet of the gas-liquid separator 4, flows through the flowmeter 5, and the test liquid is stored at the bottom of the gas-liquid separator 4; when the second valve V2 is opened, the test liquid in the gas-liquid separator 4 can be recovered.

[0062] The structure of the visible piston container 3 is as follows Figure 2~Figure 3 As shown, it includes a sleeve 31, an upper cover 32, a base 33, a piston 34, and an electric lift 35. The base 33 is fixedly arranged at one end of the sleeve 31, and the upper cover 32 is detachably arranged at the other end of the sleeve 31. In this embodiment, the upper cover 32 is fastened to the other end of the sleeve 31 by bolts. When the bolts are tightened, the upper cover 32 is fixedly connected to the sleeve 31. When the bolts are loosened, the upper cover 32 can be removed from the sleeve 31. The base 33 is slidably sleeved on the electric lift 35. One end of the electric lift 35 is fixedly connected to the lower surface of the piston 34 in the sleeve 31, that is, a part of the electric lift 35 is inside the sleeve 31, and the other part is outside the sleeve 31. When the upper cover 32 is fixed to one end of the sleeve 31, the lower surface of the upper cover 32, the inner wall of the sleeve 31 and the upper surface of the piston 34 form a sealed space.

[0063] Figure 2 In the embodiment, support columns are arranged between the upper cover 32 and the base 33 and are arranged around the outer side of the sleeve 31. For the convenience of viewing, these support columns are arranged on the Figure 3 Not drawn in. Figure 3 The middle blue part is the test liquid.

[0064] The sleeve 31 is transparent and made of a high pressure resistant material that can withstand a maximum pressure of 2 MPa.

[0065] The upper cover 32 is also provided with an air inlet 321 and an air outlet 322. The electric lift 35 reciprocates in the vertical direction, and the piston 34 is driven by the electric lift 35 and restricted by the one-way valve VT. When the piston 34 moves toward the base 33, the test gas is sucked into the visible piston container 3 from the air inlet; when the piston 34 moves toward the upper cover 32, the test gas is compressed and discharged from the air outlet of the visible piston container 3.

[0066] When there is more than one visible piston container 3 in the cylinder simulation module, the movement states of the pistons 34 in adjacent visible piston containers 3 are opposite.

[0067] In this embodiment, the electric lift 35 of the first-stage visual piston container and the electric lift 35 in the second-stage visual piston container are controlled by the same motor M (not shown in the figure). The gears between the motor M and the electric lift 35 in the first-stage visual piston container are positively meshed, and the gears between the motor M and the electric lift 35 in the second-stage visual piston container are reversely meshed. The movement speed of the electric lift 35 is 0~240 mm / s.

[0068] When there is more than one visible piston container 3 in the cylinder simulation module, the one-way valve VT is in the opposite movement state to the piston 34 in the adjacent visible piston container 3, and the one-way valve VT is arranged on the air outlet pipe of the visible piston container 3, so that the test system of the present invention ensures that the gas in the latter stage piston container will not flow back into the previous stage piston container, and can truly simulate the multi-stage compression of the test gas by two or more ion compressors connected in series.

[0069] In the test system of the present invention, the upper cover 32 of the visible piston container 3 is detachable, which is convenient for technicians to flexibly load the test liquid into the visible piston container 3 according to the test content, or replace the test liquid, or adjust the total amount of the test liquid in the visible piston container 3, thereby improving the test efficiency; at the same time, the upper cover 32 is detachable, which is also convenient for cleaning the carbon deposits generated by the test liquid in the sleeve 31 after multiple tests.

[0070] Optionally, a temperature sensor Tc, a pressure sensor Pc and a temperature controller Sv are also provided on the upper cover 32. The temperature sensor Tc is used to collect the gas temperature in the current visual piston container 3 in real time, and the pressure sensor Pc is used to collect the gas pressure in the current visual piston container 3 in real time. When the temperature collected by the temperature sensor Tc exceeds the safety temperature threshold Tmax, the temperature controller Sv issues an alarm and cuts off the power to the entire test system. The setting of the temperature controller Sv ensures the safety of the test system.

[0071] exist Figure 1 In the embodiment, the first valve V1 is connected to the first-stage visual piston container through two sections of mutually perpendicular and serially connected straight pipes, the first-stage visual piston container is connected to the first-stage check valve inlet end through two sections of mutually perpendicular and serially connected straight pipes, the first-stage check valve outlet end is connected to the second-stage visual piston container through two sections of mutually perpendicular and serially connected straight pipes, and the second-stage visual piston container is connected to the second-stage check valve inlet end through two sections of mutually perpendicular and serially connected straight pipes; a limit device 7 is provided outside these straight pipes directly connected to the visual piston container 3 ( Figure 1 For ease of viewing, Figure 1 In the figure, a straight line is circled in red and marked as A. The enlarged cross-sectional view is shown in Figure 7 As shown, Figure 7 The limiting device 7 in FIG. 1 is a cross-sectional view.

[0072] It should be emphasized that in the actual use of the gas-liquid two-phase visualization test system of the present invention, the distribution of the straight pipelines is not necessarily the same as Figure 1 For example, the first valve V1 is connected to the first-stage visible piston container only through a straight line, so the present invention is limited to setting the limit device 7 outside the straight line directly connected to the visible piston container 3.

[0073] Figure 7 is a cross-sectional view of the limiting device 7, such as Figure 7 As shown, the limiting device 7 is arranged to fit closely around the outer wall of the linear pipeline 9. Figure 7 In the figure, it can be seen that the linear pipeline 9 is tightly wrapped by the limiting device 7. The limiting device 7 includes an elastic buffer layer 71 and a rigid limiting layer 72. The elastic buffer layer 71 is tightly wrapped on the outer wall of the linear pipeline 9. The rigid limiting layer 72 has a fixed spatial position and extremely high hardness. The inner wall of the rigid limiting layer 72 is in contact with the outer wall of the elastic buffer layer 71.

[0074] In this embodiment, the elastic buffer layer 71 is made of rubber, and from the outside to the inside are the rigid limiting layer 72, the elastic buffer layer 71, and the straight pipeline 9.

[0075] The following describes in detail how the interstage buffer and the limit device 7 ensure the safety of a gas-liquid two-phase visualization test system during operation:

[0076] The intermittent intake and exhaust of the first-stage visual piston container will directly cause the pressure in the air outlet pipeline of the first-stage visual piston container to change unevenly. At the moment of exhausting the first-stage visual piston container, the pipe pressure in the air outlet pipeline of the first-stage visual piston container will suddenly increase because the cross-sectional area of ​​the straight pipe is constant. The existence of the exhaust buffer tank 61 will cause a large amount of test gas to preferentially enter the exhaust buffer tank 61 at the moment of sudden increase in the pipe pressure of the air outlet pipeline of the first-stage visual piston container, thereby ensuring that the pipe pressure in the air outlet pipeline of the first-stage visual piston container will only increase slowly to a certain extent, rather than suddenly increasing. At the same time, due to the buffering effect of the exhaust buffer tank 61, the gas entering the first-stage visual piston container will not be able to enter the exhaust buffer tank 61. The test gas in the air inlet pipeline of the secondary visual piston container will not cause a sudden increase in the pipeline pressure in the air inlet pipeline of the second-stage visual piston container; similarly, when the pipeline pressure in the air inlet pipeline of the second-stage visual piston container suddenly increases, the existence of the air inlet buffer tank 62 will cause the pipeline pressure in the air inlet pipeline of the second-stage visual piston container to increase slowly to a certain extent, rather than surging sharply; when the pipeline pressure in the air outlet pipeline of the first-stage visual piston container decreases, the test gas flows from the exhaust buffer tank 61 to the air outlet pipeline of the first-stage visual piston container, thereby ensuring that the pipeline pressure in the air outlet pipeline of the first-stage visual piston container will not decrease rapidly and significantly, but will only decrease slowly and slightly.

[0077] The intermittent intake and exhaust of the second-stage visual piston container will directly cause the pressure in the air intake pipeline of the second-stage visual piston container to change non-uniformly. When the second-stage visual piston container is inhaling air, the pipeline pressure in the air intake pipeline of the second-stage visual piston container will suddenly decrease because the cross-sectional area of ​​the straight pipeline is constant. The existence of the air intake buffer tank 62 will cause the pipeline pressure of the air intake pipeline of the second-stage visual piston container to suddenly decrease at the moment when the test gas flows from the air intake buffer tank 62 to the air intake pipeline of the second-stage visual piston container, thereby ensuring that the pipeline pressure in the air intake pipeline of the second-stage visual piston container will not decrease rapidly and significantly, but will only decrease slowly and slightly.

[0078] From the above analysis, it can be known that the inter-stage buffer section set in the test system can directly buffer the sudden change in pipeline pressure in the first-stage visual piston container outlet pipeline and the second-stage visual piston container inlet pipeline, so that the pipeline pressure in the first-stage visual piston container outlet pipeline and the second-stage visual piston container inlet pipeline will only change slowly, and the amplitude of change is also greatly reduced; and the setting of the exhaust buffer tank 61 makes it possible that the sudden change trend of pipeline pressure caused by the first-stage visual piston container basically does not affect the inlet pipeline of the second-stage visual piston container. Similarly, the setting of the intake buffer tank 62 also makes it possible that the sudden change trend of pipeline pressure caused by the second-stage visual piston container basically does not affect the inlet pipeline of the first-stage visual piston container, which avoids the phenomenon that the superposition of multiple factors causing sudden change in pipeline pressure may cause violent airflow pulsation in the first-stage visual piston container outlet pipeline and the second-stage visual piston container inlet pipeline.

[0079] Moreover, in the process of the test gas flowing from the first-stage visible piston container to the second-stage visible piston container, the work of reducing the pipeline pressure change in the air intake pipeline of the second-stage visible piston container is jointly participated by the exhaust buffer tank 61 and the air intake buffer tank 62.

[0080] The interstage buffer section greatly reduces the linear pipeline vibration caused by the airflow pulsation of the first-stage visual piston container outlet pipeline and the second-stage visual piston container inlet pipeline, which originally had the most serious airflow pulsation; however, there may still be a small amplitude of airflow pulsation in the first-stage visual piston container outlet pipeline and the second-stage visual piston container inlet pipeline. And although the original airflow pulsation of the first-stage visual piston container inlet pipeline and the second-stage visual piston container outlet pipeline is not the most serious, there is also a certain amplitude of airflow pulsation. Therefore, we set a limit device 7 outside the linear pipeline directly connected to the visual piston container 3. The outermost layer of the limit device 7 is a rigid limit layer 72 with a fixed position and hardness. Even if the internal linear pipeline 9 vibrates due to airflow pulsation, no matter how large its vibration amplitude is, it can only vibrate up and down or left and right inside the rigid limit layer 72, that is, the maximum vibration amplitude of the linear pipeline 9 is limited by the internal space of the rigid limit layer 72. Furthermore, the elastic buffer layer 71 is tightly wrapped around the outer wall of the straight pipeline 9, while the inner wall of the rigid limiting layer 72 is only in close contact with the outer wall of the elastic buffer layer 71. This is because when the straight pipeline 9 vibrates due to airflow pulsation, the elastic buffer layer 71 plays a buffering role between the straight pipeline 9 and the rigid limiting layer 72, thereby avoiding direct collision between the straight pipeline 9 and the rigid limiting layer 72, thereby extending the life of the straight pipeline 9; and during the vibration of the straight pipeline, the elastic buffer layer 71 is squeezed, which can convert part of the kinetic energy of the vibration of the straight pipeline 9 into elastic potential energy, thereby minimizing the vibration amplitude of the straight pipeline 9.

[0081] To summarize, for the straight pipelines where the air flow pulsation is not very serious, such as the first-stage visual piston container air inlet pipeline and the second-stage visual piston container air outlet pipeline, we set a limiting device 7 around the outer wall of these straight pipelines to reduce the vibration amplitude of these straight pipelines due to air flow pulsation; for the straight pipelines where the air flow pulsation is most serious, such as the first-stage visual piston container air outlet pipeline and the second-stage visual piston container air inlet pipeline, we use the inter-stage buffer to avoid the sudden change of pipeline pressure in the straight pipeline, reduce the changing speed and total changing degree of pipeline pressure, as the first air flow pulsation reduction measure in these straight pipelines, and at the same time, we also set a limiting device 7 around the outer wall of these straight pipelines to further reduce the air flow pulsation amplitude of these straight pipelines, as the second air flow pulsation reduction measure in these straight pipelines. In addition, the limit device 7 also has a bottom-up function for suppressing airflow pulsation, that is, the limit device 7 can forcibly limit the vibration range of the straight pipeline to the internal space of the limit device 7; assuming an extremely low probability, when the pipeline air pressure in the first-level visual piston container outlet pipeline suddenly increases to exceed the buffer range of the exhaust buffer tank 61, then the first-level visual piston container outlet pipeline will inevitably have relatively serious airflow pulsation, but the bottom-up function of the limit device 7 will prevent the first-level visual piston container outlet pipeline from vibrating significantly.

[0082] A gas-liquid two-phase visualization test system of the present invention can greatly reduce the airflow pulsation occurring in the straight pipeline through the interstage buffer part during the test, and cooperate with the limit device 7 wrapped outside the straight pipeline to further reduce the vibration of the straight pipeline caused by the airflow pulsation, and limit the maximum vibration amplitude of the straight pipeline, thereby suppressing the large-scale vibration of the straight pipeline caused by the airflow pulsation from multiple dimensions, improving the test efficiency, and extending the life of the straight pipeline in the test system (large-scale vibration of the straight pipeline due to airflow pulsation will seriously shorten the life of the straight pipeline), avoiding threats to the personal safety of technical personnel on site.

[0083] Optionally, the test system of the present invention further comprises an imaging module, which comprises a high-speed camera and a parallel light source. The parallel light source is arranged opposite to the lens of the high-speed camera, and the visible piston container 3 is arranged on the light irradiation path between the parallel light source and the lens of the high-speed camera.

[0084] In this embodiment, the number of parallel light sources and high-speed camera data is the same as the number of visible piston containers 3 .

[0085] The visible piston container 3 is not only convenient for technicians to observe the gas-liquid flow field during the test; together with the parallel light source and high-speed camera in the imaging module, the Tyndall effect can be used to obtain high-definition images of various details in the gas-liquid flow field during the test, which is convenient for technicians to study the impact of changes in test parameters on the stability of the gas-liquid flow field in the cylinder of the ion compressor.

[0086] The test parameters include the type of test liquid, the concentration of the test liquid, the initial temperature of the test liquid, the initial thickness of the test liquid in the visible piston container, the rotation speed of the ion compressor, the outlet pressure of the ion compressor, the specifications of the visible piston container, etc.

[0087] The initial thickness of the test liquid refers to the distance between the upper surface and the lower surface of the test liquid filled into the visual piston container 3 before the test begins.

[0088] The gas-liquid two-phase visualization test system of the present invention can also study the effects of changes in test parameters and different gas-liquid flow fields on the energy efficiency of the ion compressor, and by recovering the test liquid in the gas-liquid separator 4, study the effects of changes in test parameters and different gas-liquid flow fields on the total amount of test liquid carried out by the compressed gas.

[0089] That is, the gas-liquid two-phase visualization test system of the present invention can truly simulate the working process of the ion compressor and the multi-stage ion compressor system, which is convenient for technical personnel to conduct simulation tests efficiently and study the impact of changes in test parameters on the stability of the gas-liquid flow field in the ion compressor cylinder, the energy efficiency of the ion compressor, and the total amount of ion liquid carried out by the compressed gas.

[0090] In this embodiment, the test gas is an inert gas, that is, the gas source 1 contains an inert gas.

[0091] Example 2

[0092] This embodiment provides a safe operation method of a gas-liquid two-phase visualization test system, which is applied to a gas-liquid two-phase visualization test system as described in Example 1, and includes the following steps:

[0093] S1, presetting various test parameters in a gas-liquid two-phase visualization test system according to the test conditions;

[0094] S2, fix the upper cover 32 on the sleeve 31, open the first valve V1, the third valve V3, the one-way valve VT and the fourth valve V4, start the motor M to start the test, the motor M drives the piston 34 to reciprocate in the vertical direction through the electric lift 35, the working condition of the ion compressor cylinder in the visual piston container 3 is simulated, various sensors and flow meters collect data, and at the same time, the high-speed camera takes the gas-liquid flow field image in the visual piston container 3;

[0095] S3, when the current test is finished, a gas-liquid two-phase visualization test system is powered off, and the second valve V2 is opened to recover the test liquid in the gas-liquid separator 4.

[0096] The safe operation of a gas-liquid two-phase visualization test system is a method for conducting a safety test using a gas-liquid two-phase visualization test system.

[0097] During the test, the exhaust buffer tank 61 and the intake buffer tank 62 in the interstage buffer section reduce the speed and amplitude of the pipeline pressure change in the linear pipelines in the test system by storing and releasing the test gas. The limit device 7 limits the amplitude of vibration of each linear pipeline due to air flow pulsation, ensuring the safe operation of the test system during the entire test process and ensuring the safe conduct of the test.

[0098] The data collected by the sensors and flow meters, and the gas-liquid flow field images in the visible piston container 3 taken by the high-speed camera are all test data.

[0099] In S1, the test conditions are carried out according to the test subject of the technician. For example, if the test subject is to study the influence of the initial temperature of the test gas on the stability of the gas-liquid flow field, then according to the control variable method, the set temperature of the preheating device is used as the main variable, and other test parameters except the main variable are recorded as secondary variables.

[0100] The technicians developed several test conditions and divided these test conditions into several test groups. In each test group, except for the main variables, the other secondary variables are the same; there is at least one different secondary variable between different test groups.

[0101] In S1, "presetting the test parameters in a gas-liquid two-phase visualization test system" includes presetting: the type of test gas, the type of test liquid, the concentration of the test liquid, the set temperature of the preheating device 2, the initial thickness of the test liquid in the visual piston container 3, the outlet pressure of the first valve V1, the outlet pressure of the fourth valve V4, the rotation speed of the motor M, the specifications of the visual piston container 3, the top dead center position of the piston 34, and the duration of this test.

[0102] The top dead center position of the piston 34 needs to be adjusted according to the initial thickness of the test liquid in the visual piston container 3. The piston 34 needs to reserve space for the test liquid during the reciprocating operation, so the top dead center position of the piston 34 is adjusted according to the initial thickness of the test liquid used in this test.

[0103] When a gas-liquid two-phase visualization test system includes two or more visual piston containers 3, the outlet pressure of the first valve V1 is set, that is, the inlet pressure of the first-stage visual piston container is set; the outlet pressure of the fourth valve V2 is set, that is, the final compressed gas pressure is set, and the pressures of the visual piston containers 3 connected in series are self-balanced, so the technicians do not need to set the inlet pressure of any visual piston container except the first-stage visual piston container, nor do they need to set the outlet pressure of any visual piston container except the last-stage visual piston container.

[0104] In an actual multi-stage ion compressor system connected in series, the final compressed gas is obtained through compression by the multi-stage compressors, but technicians cannot accurately know the pressure ratio of each ion compressor, which may make the current multi-stage ion compressor system not the optimal design and affect the safety of the multi-stage ion compressor system (for example, in the actual working process, if the actual pressure ratio of the ion compressor in the multi-stage ion compressor system slightly exceeds / is stuck at the maximum pressure ratio critical value, the safety of the entire multi-stage ion compressor system will be greatly challenged), and it also brings difficulties to the optimization work of reducing the total energy consumption of the multi-stage ion compressor system.

[0105] The test method of the present invention can simulate a real multi-stage ion compressor system by controlling the intake pressure of the first-stage visual piston container and the final compressed gas pressure, and collect the gas pressure and temperature in each visible piston container 3 through each temperature sensor Tc and pressure sensor Pc, and can convert the pressure ratio distribution of each ion compressor in real time, which is helpful to optimize the design of the multi-stage ion compressor system and improve the safety of the multi-stage ion compressor system.

[0106] In the test method of the present invention, the test liquid in the gas-liquid separator 4 is recovered, which saves costs on the one hand, and measures the total amount of test liquid brought out by the compressed gas in each test on the other hand, which is used to guide the subsequent development of ionic liquids and calibrate the appropriate thresholds of various test parameters in the ion compressor. We hope that the ionic liquid brought out by the compressed gas is as little as possible, and the ionic liquid also plays a lubricating role in the cylinder of the ion compressor. Otherwise, as the compressed gas is continuously generated, the ionic liquid becomes less and less, and the increase in friction will cause the temperature in the cylinder of the ion compressor to rise sharply, thereby causing damage to the ion compressor and poor compression effect. At the same time, frequent replenishment of ionic liquid will also greatly increase costs.

[0107] Example 3

[0108] The present invention also provides a data processing method for a gas-liquid flow field visualization test, which uses the test data obtained by the safe operation method of a gas-liquid two-phase visualization test system as described in Example 2, including the following contents:

[0109] Based on the temperature sensor Tc and the pressure sensor Pc in the visible piston container 3, the compression efficiency of the two-stage series visible piston container is calculated; at the same time, all the gas-liquid flow field images in the current test are analyzed, and the total droplet sputtering intensity in each gas-liquid flow field image is calculated; at the same time, the total amount of test liquid in the gas-liquid separator 4 after each test is recorded.

[0110] "Calculate the efficiency of a two-stage series ion compressor system" includes the following specific contents:

[0111] At the same time, the temperature sensor Tc value in the first-stage visual piston container is recorded as T1, the pressure sensor Pc value is recorded as P1, the temperature sensor Tc value in the second-stage visual piston container is recorded as T2, the pressure sensor Pc value is recorded as P2, and the compression efficiency of the two-stage series visual piston container is calculated. :

[0112] ,

[0113] Here, κ represents the polytropic index of the test gas.

[0114] Using the pressure similarity criterion, gas property equation, and combined with the temperature change during the compression process, for two geometrically similar flows, when the pressure is similar, the Euler numbers at their corresponding points must be equal, so we get the compression efficiency of the two-stage series visual piston container .

[0115] During the test, when the piston 34 moves toward the upper cover 32, the state of the test liquid is as follows: Figure 4 As shown; the moment the piston 34 moves to the top dead center, the piston 34 stops moving, but at this time the test liquid is still moving toward the upper cover 32 due to inertia. At this time, the upper surface of the test liquid produces fluctuations, and the lower surface of the test liquid produces splashing droplets due to gravity. At this time, the state of the test liquid is as follows Figure 5 As shown; when the piston 34 moves toward the base 33, the piston container 3 is exhausted. At this time, there are not only fluctuations on the upper surface of the test liquid, but also splashing droplets. At this time, the state of the test liquid is as follows Figure 6 shown. Figure 4~Figure 6 The states of the test liquid and test gas will be recorded by the gas-liquid flow field image. Figure 4~Figure 6 The middle blue part represents the test liquid. The air inlet 321 and the air outlet 322 of the upper cover 32 are not in the Figure 4~Figure 6 Draw it in.

[0116] "Analysis of gas-liquid flow field images" includes the following specific contents:

[0117] The fluctuation condition of the test liquid, the droplet splashing condition, the bubble content in the test liquid, and the degree of separation between the test liquid and the piston 34 in the gas-liquid flow field image are observed and recorded.

[0118] The fluctuation conditions of the test liquid include wave crests and troughs on the upper surface of the test liquid and wave crests and troughs on the lower surface of the test liquid.

[0119] The droplet splashing condition includes the droplet splashing angle, droplet splashing shape, and splashing velocity of the test liquid. A certain splashing velocity can be calculated from two gas-liquid flow field images that are adjacent in time.

[0120] The degree of separation between the test liquid and the piston 34 refers to the maximum distance between the lower surface of the test liquid and the upper surface of the piston 34 at a certain moment.

[0121] The stable state of the gas-liquid flow field refers to the situation where the test liquid is tightly fitted to the piston 34 , there is no fluctuation on the upper surface of the test liquid, and there is no splashing droplet in the visible piston container 3 .

[0122] When the test liquid is separated from the piston 34, gas exists between the lower surface of the test liquid and the upper surface of the piston 34. When the lower surface of the test liquid is again attached to the upper surface of the piston 34, the gas originally existing between the lower surface of the test liquid and the upper surface of the piston 34 will inevitably pass through the test liquid in the form of bubbles and gather between the upper surface of the test liquid and the lower surface of the upper cover 32. Therefore, the separation of the test liquid from the piston 34 will inevitably lead to the generation of splashing droplets and bubbles in the test liquid, and the splashing droplets and bubbles in the test liquid will react to the fluctuation of the test liquid, making the gas-liquid flow field in the visible piston container 3 no longer stable.

[0123] From the perspective of energy conservation, the more unstable the gas-liquid flow field is, the more energy is consumed in the process of compressing the test gas. Therefore, whether the technicians are developing ionic liquids, designing new ion compressors, or calibrating the parameters of the ion compressors for the best operating state, the standard is always to make the gas-liquid flow field as stable as possible.

[0124] "Calculate the total droplet splash intensity in each gas-liquid flow field image" includes the following specific contents:

[0125] In the gas-liquid flow field image, the distance between the lower surface of the upper cover 32 and the upper surface of the test liquid is recorded as L0. When there is fluctuation on the upper surface of the test liquid, L0 is the arithmetic mean of the distance between the lower surface of the upper cover 32 and the fluctuation surface of the test liquid.

[0126] The vertical distance between the lower surface of the upper cover 32 and the center of the i-th sputtering droplet in the current gas-liquid flow field image is L i , i is a positive integer; then the sputtering intensity L of the i-th sputtering droplet in the current gas-liquid flow field image is d,i For L d,i =(L0-L i ) / L0,

[0127] Note that there are n sputtering droplets in the current gas-liquid flow field image, then the total droplet sputtering intensity L in the current gas-liquid flow field image is d,total : .

[0128] Technicians analyze and study the gas-liquid flow field images to comprehensively determine the stability of the gas-liquid flow field, which will help technicians to formulate more detailed and accurate gas-liquid flow field stability judgment standards in the future.

[0129] Furthermore, the analysis and determination of the stability of the gas-liquid flow field, as well as the total droplet sputtering intensity corresponding to each gas-liquid flow field image, are also used to help technicians calibrate the maximum threshold of the total droplet sputtering intensity of the ion compressor. If the total droplet sputtering intensity is below the maximum threshold of the total droplet sputtering intensity, the overall energy consumption of the current ion compressor is within the allowable range. If the total droplet sputtering intensity is greater than the maximum threshold of the total droplet sputtering intensity, the overall energy consumption of the current ion compressor is too high, exceeding the allowable range, and may even cause damage to the ion compressor. Therefore, calibrating the maximum threshold of the total droplet sputtering intensity of the ion compressor can also be used to guide the development of ionic liquids and the design of ion compressors.

[0130] "Recording the total amount of test liquid in the gas-liquid separator 4 after each test" is also used to guide the development of ionic liquids, the design of ion compressors, and to assist in calibrating the parameters of the ion compressor for optimal operation. We hope that the total amount of test liquid in the gas-liquid separator 4 after each test is as small as possible.

[0131] Acquiring the data collected by the temperature sensor Tc and the pressure sensor Pc in the visible piston container 3 and calculating the compression efficiency of the two-stage series visible piston container can effectively help technicians verify the safety of the designed two-stage series ion compressor system. The technicians can also continuously optimize the structure of the ion compressor system in the direction of improving the compression efficiency.

[0132] Technicians can also use the data processing method of the gas-liquid flow field visualization experiment of the present invention to comprehensively study the relationship between the stability of the gas-liquid flow field, the capacity of ion liquid brought out by the compressed gas, and the compression efficiency of the multi-stage ion compressor, and further guide the development of ion liquids, the design of ion compressors, and the structural optimization of ion compressor systems.

[0133] From the above analysis, it can be seen that the data processing method of the gas-liquid flow field visualization test of the present invention can obtain important data in the working process of the ion compressor, such as the capacity of the ion liquid brought out by the compressed gas, the relevant data of the gas-liquid flow field stability, and the compression efficiency of the two-stage ion compressor. It will not only help technicians to formulate more accurate gas-liquid flow field stability judgment standards in the future and calibrate the maximum threshold of the total droplet sputtering intensity of the ion compressor, but also help to verify the safety of the multi-stage ion compressor system, and guide technicians in the development of ionic liquids, the design of ion compressors, the structural optimization of ion compressor systems, and the parameter calibration of the ion compressor for the optimal operating state.

[0134] The technology, shape, and structure parts not described in detail in the present invention are all well-known technologies. It should also be pointed out that the above are only preferred embodiments of the present invention and are not intended to limit the present invention. The components or steps in the embodiments of the present invention can be decomposed and / or recombined, and these decompositions and / or recombinations should be regarded as equivalent solutions of the present application and should fall within the protection scope of the present invention.

Claims

1. A safe operation method of a gas-liquid two-phase visualization test system, characterized in that: The operation method is applied to a gas-liquid two-phase visual test system, the gas-liquid two-phase visual test system comprising an air intake module, a cylinder simulation module, and an air outlet module connected in series in sequence, the cylinder simulation module comprising two or more stages of visual piston units connected in series, each visual piston unit comprising a visual piston container (3) and a one-way valve VT, the one-way valve VT being arranged on the air outlet pipeline of the visual piston container (3), the visual piston container (3) being transparent and containing a test liquid; an interstage buffer for temporarily storing the test gas is also arranged on the pipeline between adjacent visual piston containers (3); a limit device (7) is arranged outside the straight pipeline directly connected to the visual piston container (3); The air intake module generates test gas, which flows through the visible piston units connected in series in the cylinder simulation module in sequence, and the visible piston container (3) in the visible piston unit performs a piston reciprocating motion to compress the test gas and then sends it to the air outlet module, and the air outlet module discharges the compressed gas into the surrounding environment; The gas outlet module comprises a gas-liquid separator (4), a flow meter (5) and a fourth valve V4 which are connected in series in sequence along the test gas transmission direction, and the gas outlet of the fourth valve V4 is connected to the surrounding environment, and the fourth valve V4 controls the final pressure of the compressed gas; The visible piston container (3) comprises a sleeve (31), an upper cover (32), a base (33), a piston (34) and an electric lift (35); the sleeve (31) is transparent; the piston (34) is arranged in the sleeve (31); the base (33) is fixedly arranged at one end of the sleeve (31); the upper cover (32) is detachably arranged at the other end of the sleeve (31); the base (33) is sleeved on the electric lift (35); one end of the electric lift (35) is fixedly connected to the lower surface of the piston (34); and the electric lift (35) has a The piston (34) is driven to reciprocate in the sleeve (31) along the length direction of the sleeve (31); when the upper cover (32) is fixed to one end of the sleeve (31), the lower surface of the upper cover (32), the inner wall of the sleeve (31) and the upper surface of the piston (34) form a sealed space, and the test liquid is located in the sealed space; the upper cover (32) is also provided with an air inlet (321) and an air outlet (322); the pistons (34) in adjacent visible piston units have opposite operating states; the upper cover (32) is also provided with a temperature sensor Tc and a pressure sensor Pc; The interstage buffer section comprises an exhaust buffer tank (61) and an intake buffer tank (62), wherein the exhaust buffer tank (61) is arranged on a pipeline between a visible piston container (3) of a current visible piston unit and a one-way valve VT, and the intake buffer tank (62) is arranged on a pipeline between the one-way valve VT of the current visible piston unit and a visible piston container (3) of a next-stage visible piston unit; The limiting device (7) comprises an elastic buffer layer (71) and a rigid limiting layer (72), wherein the elastic buffer layer (71) is tightly wrapped around the outer wall of the linear pipeline, the inner wall of the rigid limiting layer (72) is in close contact with the outer wall of the elastic buffer layer (71), and the spatial position of the rigid limiting layer (72) is fixed; A gas-liquid two-phase visualization test system further comprises an imaging module, the imaging module comprising a camera and a parallel light source, the parallel light source and the camera lens being arranged opposite to each other, the visual piston container (3) being arranged on a light irradiation path between the parallel light source and the camera lens, the camera being used to photograph the test liquid in the visual piston container (3); The air intake module comprises an air source (1), a preheating device (2) and a first valve V1 which are connected in series in sequence along the transmission direction of the test gas; The safe operation method of the gas-liquid two-phase visualization test system includes the following steps: S1, presetting various test parameters in a gas-liquid two-phase visualization test system according to the test conditions; The test parameters include the type of test gas, the type of test liquid, the concentration of the test liquid, the set temperature of the preheating device (2), the initial thickness of the test liquid in the visual piston container (3), the outlet pressure of the first valve V1, the outlet pressure of the fourth valve V4, the movement speed of the electric lift (35), the specifications of the visual piston container (3), the top dead center position of the piston (34), and the duration of the test; S2, fix the upper cover (32) on the sleeve (31), open the first valve V1, the one-way valve VT and the fourth valve V4, start the electric lift (35), each electric lift (35) drives the piston (34) to reciprocate in the vertical direction, and the working conditions in the cylinder of the ion compressor are simulated in the visible piston container (3), and the test data of the current test are obtained: each sensor and flow meter collect data, and at the same time, the camera takes an image of the gas-liquid flow field in the visible piston container (3); S3, when the current test ends, a gas-liquid two-phase visualization test system is powered off, and the gas outlet module uses a gas-liquid separator (4) to collect the test liquid in the gas outlet pipeline of the cylinder simulation module; In S2, the exhaust buffer tank (61) and the intake buffer tank (62) reduce the speed and amplitude of the change of the pipeline gas pressure of the linear pipeline in the test system by storing and releasing the test gas, and the limit device (7) limits the vibration amplitude of each linear pipeline.

2. A data processing method for a gas-liquid flow field visualization test, which uses a safe operation method for a gas-liquid two-phase visualization test system as described in claim 1 to obtain test data, comprising the following contents: a gas-liquid two-phase visualization test system includes a two-stage visual piston unit connected in series, and based on the temperature sensor Tc data and the pressure sensor Pc data in the visual piston container (3), the compression efficiency of the two-stage visual piston container in series is calculated; at the same time, all gas-liquid flow field images in the current test are analyzed, and the total droplet sputtering intensity in each gas-liquid flow field image is calculated; and the total amount of test liquid in the gas-liquid separator (4) after each test is recorded.

3. The data processing method for gas-liquid flow field visualization test according to claim 2 is characterized by: Calculate the compression efficiency of a two-stage visible piston container in series, including the following details: At a certain moment, the value of the temperature sensor Tc in the first-stage visual piston container is recorded as T1, the value of the pressure sensor Pc is recorded as P1, the value of the temperature sensor Tc in the second-stage visual piston container is recorded as T2, the value of the pressure sensor Pc is recorded as P2, and the compression efficiency η of the two-stage visual piston container in series is calculated: η=( , where κ represents the polytropic index of the test gas; The analysis of the gas-liquid flow field image includes the following specific contents: Observe and record the fluctuation condition of the test liquid, the droplet splashing condition, the bubble content in the test liquid, and the degree of separation between the test liquid and the piston (34) in the gas-liquid flow field image; The fluctuation condition of the test liquid includes the peaks and valleys on the upper surface of the test liquid and the peaks and valleys on the lower surface of the test liquid; The droplet splashing condition includes the splashing droplet angle, splashing droplet shape and splashing speed of the test liquid; The degree of separation between the test liquid and the piston (34) refers to the maximum distance between the lower surface of the test liquid and the upper surface of the piston (34) in the current gas-liquid flow field image; Calculate the total droplet splash intensity in each gas-liquid flow field image, including the following details: In the gas-liquid flow field image, the distance between the lower surface of the upper cover (32) and the upper surface of the test liquid is recorded as L0. When there is fluctuation on the upper surface of the test liquid, L0 is the arithmetic mean of the distance between the lower surface of the upper cover (32) and the fluctuation surface of the test liquid. Note that there are n sputtering droplets in the current gas-liquid flow field image, and the vertical distance between the lower surface of the upper cover (32) and the center of the i-th sputtering droplet in the current gas-liquid flow field image is L i , 1≤i≤n and i is a positive integer, then the sputtering intensity L of the i-th sputtering droplet in the current gas-liquid flow field image is d,i For L d,i =(L0-L i ) / L0; the total droplet sputtering intensity L in the current gas-liquid flow field image d,total :L d,total = .

Images