A gas-liquid two-phase visualization test system, test 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 test method, and a data processing method. A gas-liquid two-phase visualization test system includes an air intake module, a cylinder simulation module, and an air outlet module connected in series in sequence. The cylinder simulation module is transparent and has a test liquid built in. The air intake module generates a test gas, and the test gas enters the cylinder simulation module. The piston in the cylinder simulation module reciprocates 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-liquid two-phase visualization test system of the present invention can realistically and efficiently simulate the complex gas-liquid flow field in the cylinder of the ion compressor and perform observation and analysis, which helps the research and development of ion compressors and ionic liquids.

Description

Technical Field

[0001] The invention belongs to the technical field of ion compressors, and in particular relates to a gas-liquid two-phase visualization test system, a test 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] 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, solving 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. Using ion compressors can effectively improve compression efficiency and reduce energy consumption.

[0004] There are few ion compressors on the market, but these ion compressors are not only costly but also cannot meet the needs of consumers well due to the limited choices. Currently, the market for ion compressors is relatively blank and has huge potential. It is necessary to accelerate the research and development of ion compressors. The core of the research and development of ion compressors lies in how to simulate and observe the complex gas-liquid flow field in the cylinder of the ion compressor. Summary of the invention

[0005] The purpose of the present invention is to overcome the deficiencies of the above-mentioned prior art and provide a gas-liquid two-phase visualization test system that can realistically and efficiently simulate and observe the complex gas-liquid flow field in the cylinder of an ion compressor, thereby facilitating the research and development of ion compressors and ionic liquids.

[0006] To achieve the above object, the present invention adopts the following technical solutions:

[0007] A gas-liquid two-phase visualization test system comprises an air intake module, a cylinder simulation module and an air outlet module which are sequentially connected in series along the test gas transmission direction. The cylinder simulation module is transparent and has a test liquid built in it. The air intake module generates a test gas, and the test gas enters the cylinder simulation module. The piston in the cylinder simulation module reciprocates 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.

[0008] Preferably, the cylinder simulation module includes more than one level of visible piston units connected in series, the visible piston unit includes a visible piston container and a one-way valve, the one-way valve is arranged on the air outlet pipe of the visible piston container, and the test liquid is contained in the visible piston container.

[0009] Preferably, the gas outlet module comprises a gas-liquid separator, a flow meter and a fourth valve which are connected in series in sequence, 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; when the cylinder simulation module includes two or more visual piston units connected in series, the operating states of the pistons in adjacent visual piston units are opposite.

[0011] Preferably, the upper cover is also provided with a temperature sensor and a pressure sensor.

[0012] 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.

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

[0015] S1, presetting various test parameters in a gas-liquid two-phase visualization test system according to the test conditions;

[0016] 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;

[0017] 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;

[0018] 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 to collect the test liquid in the gas outlet pipeline of the cylinder simulation module.

[0019] The present invention also provides a data processing method for a gas-liquid flow field visualization test, which uses a gas-liquid two-phase visualization test method 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.

[0020] Preferably, the compression efficiency of the two-stage visible piston container connected in series is calculated, including the following specific contents:

[0021] 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. :

[0022] , where κ represents the polytropic index of the test gas;

[0023] The analysis of the gas-liquid flow field image includes the following specific contents:

[0024] 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;

[0025] 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;

[0026] The droplet splashing condition includes the splashing droplet angle, splashing droplet shape and splashing speed of the test liquid;

[0027] 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;

[0028] Calculate the total droplet splash intensity in each gas-liquid flow field image, including the following details:

[0029] 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;

[0030] 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 : .

[0031] The beneficial effects of the present invention are:

[0032] (1) The gas-liquid two-phase visualization test system of the present invention can realistically simulate the working process of an ion compressor and a multi-stage ion compressor system, making it convenient 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.

[0033] (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.

[0034] (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.

[0035] (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.

[0036] (5) 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 Tc and pressure sensor Pc, and 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.

[0037] (6) 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.

[0038] (7) 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

[0039] Figure 1 It is a schematic diagram of the overall structure of a gas-liquid two-phase visualization test system of the present invention;

[0040] Figure 2 It is a schematic diagram of the overall structure of the visual piston container of the present invention;

[0041] Figure 3 is a cross-sectional view of a visible piston container of the present invention;

[0042] Figure 4 It is a schematic diagram of the state of the test liquid when the visible piston container is exhausted during the test;

[0043] Figure 5It 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;

[0044] Figure 6 This is a schematic diagram of the state of the test liquid when air is sucked into the visual piston container during the test. DETAILED DESCRIPTION

[0045] 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.

[0046] Example 1

[0047] 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.

[0048] 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.

[0049] 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.

[0050] In this embodiment, the first valve V1 is an electric valve.

[0051] 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.

[0052] 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.

[0053] 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.

[0054] In this embodiment, the cylinder simulation module includes two-stage visual piston units, the visual piston unit 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 unit far from the air intake module is recorded as the second-stage visual piston container, 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, and 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.

[0055] 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.

[0056] In this embodiment, the fourth valve V4 is a back pressure valve.

[0057] 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 and flows through the flow meter 5, while 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 flowed into the gas-liquid separator 4.

[0058] Recycling is allowed.

[0059] The structure of the visible piston container 3 is as follows Figure 2~Figure 3As 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.

[0060] 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.

[0061] The sleeve 31 is transparent and made of a high pressure resistant material that can withstand a maximum pressure of 2 MPa.

[0062] 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.

[0063] 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.

[0064] 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.

[0065] 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.

[0066] 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.

[0067] 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.

[0068] 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.

[0069] 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 .

[0070] 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.

[0071] 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.

[0072] 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.

[0073] 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.

[0074] 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.

[0075] In this embodiment, the test gas is an inert gas, that is, the gas source 1 contains an inert gas.

[0076] Example 2

[0077] This embodiment provides a gas-liquid two-phase visualization test method, which is applied to a gas-liquid two-phase visualization test system as described in Embodiment 1, and includes the following steps:

[0078] S1, presetting various test parameters in a gas-liquid two-phase visualization test system according to the test conditions;

[0079] 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;

[0080] 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.

[0081] 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.

[0082] 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.

[0083] 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.

[0084] 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.

[0085] 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.

[0086] 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.

[0087] 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.

[0088] 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.

[0089] 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.

[0090] Example 3

[0091] The present invention also provides a data processing method for a gas-liquid flow field visualization test, which uses a gas-liquid two-phase visualization test method as described in Example 2 to obtain test data, including the following contents:

[0092] 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.

[0093] "Calculate the efficiency of a two-stage series ion compressor system" includes the following specific contents:

[0094] 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. :

[0095] ,

[0096] Here, κ represents the polytropic index of the test gas.

[0097] 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 .

[0098] 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.

[0099] "Analysis of gas-liquid flow field images" includes the following specific contents:

[0100] 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.

[0101] 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.

[0102] 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.

[0103] 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.

[0104] 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 .

[0105] 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.

[0106] 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.

[0107] "Calculate the total droplet splash intensity in each gas-liquid flow field image" includes the following specific contents:

[0108] 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.

[0109] 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,

[0110] 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 : .

[0111] 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.

[0112] 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.

[0113] "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.

[0114] 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.

[0115] 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.

[0116] 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.

[0117] 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 gas-liquid two-phase visualization test method, characterized in that: The test method includes a gas-liquid two-phase visualization test system, which includes an air intake module, a cylinder simulation module, and an air outlet module connected in series in sequence. The cylinder simulation module is transparent and has a test liquid built in it. The air intake module generates a test gas, and the test gas enters the cylinder simulation module. The piston in the cylinder simulation module reciprocates to compress the test gas and then sends it to the air outlet module. The air outlet module discharges the compressed gas into the surrounding environment. The cylinder simulation module comprises more than one level of visual piston units connected in series, the 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), and the visual piston container (3) containing a test liquid; 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 in contact with the The lower surface of the piston (34) is fixedly connected, and the electric lift (35) drives the piston (34) 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); When the cylinder simulation module includes two or more visible piston units connected in series, 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 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; It also includes an imaging module, the imaging module includes a camera and a parallel light source, the parallel light source and the camera lens are arranged opposite to each other, the visible piston container (3) is arranged on the light irradiation path between the parallel light source and the camera lens, and the camera is used to photograph the test liquid in the visible piston container (3); Gas-liquid two-phase visualization test method The following steps are involved: S1, pre-setting various test parameters in the 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 is finished, the gas-liquid two-phase visualization test system is powered off, and the gas outlet module uses the gas-liquid separator (4) to collect the test liquid in the gas outlet pipeline of the cylinder simulation module; The test data is processed, including the following contents: the 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 connected in series is calculated; at the same time, all gas-liquid flow field images in the current test are analyzed, and the total droplet splashing intensity in each gas-liquid flow field image is calculated; Record the total amount of test liquid in the gas-liquid separator (4) after each test; 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 = .

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