Iodine vapor flow testing device and method

Abstract

The invention provides an iodine vapor flow test device and method, and the device comprises an iodine working medium flow measurement module which comprises a balance, an iodine collection tank, an iodine vapor adsorption solvent and a gas path supply system, the iodine vapor adsorption solvent is placed in the iodine collection tank, the collection tank is installed on the balance, and the gas path supply system is connected with the iodine working medium flow measurement module; the mass of incoming flow is measured by dissolving iodine vapor with an iodine vapor adsorption solvent; and the iodine working medium storage and supply module is used for heating the solid iodine working medium to a gaseous state and conveying the gaseous iodine working medium into an iodine collecting tank. During testing, solid iodine is heated to gaseous iodine through the iodine working medium storage and supply module, the gaseous iodine is conveyed into an iodine vapor adsorption solvent in the iodine collecting tank, the adsorption solvent has the effects of absorbing the iodine vapor and cooling at the same time, it is ensured that the iodine vapor is completely dissolved into the adsorption solvent, and the quality of the iodine vapor is measured by measuring the quality change of the iodine collecting tank. The real-time flow of the iodine working medium can be calculated, and the flow test and calibration of the iodine storage and supply system are completed.

Description

Technical Field

[0001] The invention relates to the technical field of electric propulsion working fluid supply systems, and in particular to an iodine vapor flow rate testing device and method. Background Art

[0002] With the development of aerospace propulsion technology, electric propulsion technology has become increasingly mature. It has the characteristics of high specific impulse, small thrust, repeatable start-up and long life. It can significantly reduce the launch mass of spacecraft and has significant application prospects in satellite attitude control, orbit correction, orbit maintenance and power compensation.

[0003] Electric propulsion is a propulsion technology that uses electric energy to heat or ionize a working fluid to generate plasma, and accelerates the propellant through electric energy to generate thrust. At present, xenon is the mainstream working fluid for electric propulsion, but as the demand for electric propulsion technology in space applications increases year by year, the use of xenon is also increasing. However, the stock of xenon in the atmosphere is extremely low. The large-scale application of electric propulsion has led to a more serious shortage of xenon, and the cost of the working fluid is getting higher and higher, which affects the large-scale application of electric propulsion. Therefore, there is an urgent need for a low-cost substance to replace xenon as an electric propulsion working fluid.

[0004] Compared with xenon, iodine has the advantages of high-density storage (solid at room temperature), low price, similar relative atomic mass and ionization energy to xenon, and similar discharge characteristics as xenon, so it can be used as an excellent alternative to xenon. However, the problem with iodine as a working fluid is that it is corrosive and the iodine vapor temperature is high. Traditional flow sensors cannot work in an iodine atmosphere, and the iodine flow cannot be measured in real time using traditional methods. Therefore, a device that can measure the iodine flow in the iodine storage and supply system is needed to calibrate the iodine flow when the thruster is working.

[0005] Patent document CN115452079A (application number: 202110644824.2) discloses a flow measurement device and control method for a solid iodine working medium storage and supply system, which belongs to the field of aerospace electric propulsion technology, and is used to solve the problems of measuring and controlling the mass flow of iodine working medium in an electric propulsion system with solid iodine as the working medium. The flow measurement device includes an iodine vapor supply unit, an iodine vapor collection unit and a vacuum pump (7); one end of the iodine vapor collection unit is detachably connected to the iodine vapor supply unit, and the other end is detachably connected to the vacuum pump (7); the iodine vapor supply unit includes a steam generating tank (1) and a generating tank heater (3), and the generating tank heater (3) is used to heat the solid iodine working medium (2) in the steam generating tank (1); the iodine vapor collection unit includes a collecting chamber (8) and a refrigerator (9), and the refrigerator (9) is used to reduce the temperature in the collecting chamber (8). It is suitable for controlling the mass flow of iodine working medium in an electric propulsion system with solid iodine as the working medium. Summary of the invention

[0006] In view of the defects in the prior art, the object of the present invention is to provide an iodine vapor flow rate testing device and method.

[0007] According to the present invention, an iodine vapor flow measurement device comprises: an iodine working medium flow measurement module and an iodine working medium storage and supply module;

[0008] The iodine working medium flow measurement module and the iodine working medium storage and supply module are connected through a pipeline;

[0009] The iodine working medium storage and supply module is used to heat the solid iodine working medium to a gaseous state, and transmit the iodine vapor to the iodine collecting tank 2 in the iodine working medium flow measurement module, and utilize the iodine absorption solvent 3 in the iodine collecting tank 2 to dissolve the iodine to achieve real-time measurement of the flow rate;

[0010] The iodine working fluid flow measurement module is placed in a vacuum environment.

[0011] Preferably, the iodine working medium storage and supply module comprises: a throttle 9, an on-off solenoid valve 10, an exhaust valve 11, a pressure sensor 12 and an iodine storage tank 13;

[0012] The iodine storage tank 13 in the iodine working medium storage and supply module is connected to the iodine collection tank 2 in the iodine working medium flow measurement module through a pipeline;

[0013] In the iodine working medium storage and supply module, the throttle 9, the on-off solenoid valve 10, the exhaust valve 11 and the pressure sensor 12 are provided on the pipeline connecting the iodine storage tank 13 and the iodine collection tank 2;

[0014] The iodine storage tank 13 is used to store iodine;

[0015] The pressure sensor 12 is used to measure the iodine vapor pressure at the outlet of the iodine storage tank 13;

[0016] The exhaust valve 11 is used to exhaust the air in the iodine storage tank 13 and the pipeline;

[0017] The on-off solenoid valve 10 is used to control the on-off of the pipeline of the iodine working medium storage and supply module;

[0018] The throttle 9 is used to control the iodine flow.

[0019] Preferably, the iodine working medium flow measurement module comprises: an exhaust valve 6, an on-off solenoid valve 7, and a pressure sensor 8;

[0020] The iodine collecting tank 2 in the iodine working medium flow measurement module is connected to the iodine storage tank 13 in the iodine working medium storage and supply module through a pipeline;

[0021] In the iodine working medium flow measurement module, the exhaust valve 6, the on-off solenoid valve 7 and the pressure sensor 8 are provided on the pipeline connecting the iodine collecting tank 2 and the iodine storage tank 13;

[0022] The exhaust valve 6 is used to remove air from the transport pipeline;

[0023] The on-off solenoid valve 7 is used to control the on-off of the pipeline;

[0024] The pressure sensor 8 is used to measure the gas pressure in the pipeline.

[0025] Preferably, the iodine working fluid flow measurement module further includes a balance 1;

[0026] The iodine collecting tank 2 filled with the iodine absorbing solvent 3 is placed on the balance 1, and the mass of iodine absorbed in real time is weighed using the balance 1.

[0027] Preferably, the iodine working medium flow measurement module further includes a filter screen 4 and an air stone;

[0028] The filter screen 4 is arranged at the port extending into the pipeline of the iodine absorption solvent 3, and the bubble stone is arranged at the port of the pipeline of the iodine absorption solvent 3 to ensure sufficient absorption of iodine vapor.

[0029] Preferably, the iodine working medium flow measurement module further includes a pipeline lifter 5;

[0030] The pipeline lifter 5 is arranged on the pipeline extending into the iodine absorption solvent 3 , and is used to control the depth of the pipeline extending into the iodine absorption solvent 5 .

[0031] Preferably, the opening aperture of the iodine collecting tank 2 is larger than the diameter of the pipeline extending into the iodine absorbing solvent 3 and meets the preset requirements.

[0032] Preferably, the iodine absorption solvent 3 is a solvent with an iodine solubility greater than a preset value and a theoretical saturated vapor pressure of 0, which is used for cooling and absorbing iodine vapor, and an ionic liquid is used as the solvent.

[0033] According to an iodine vapor flow measurement method provided by the present invention, the following steps are performed using the iodine vapor flow measurement device described above:

[0034] Step S1: opening the on-off solenoid valve and the exhaust valve in the iodine working medium flow measurement module and the iodine working medium storage and supply module to exhaust the air in the iodine working medium flow measurement module and the iodine working medium storage and supply module into a vacuum;

[0035] Step S2: closing the exhaust valve and the solenoid valve, controlling the pipeline lifter 5 to extend the pipeline into the iodine absorption solvent 3, heating the iodine working medium flow measurement module and the iodine working medium storage and supply module, and heating the solid iodine in the iodine working medium storage and supply module to gaseous iodine;

[0036] Step S3: opening the solenoid valve, and the gaseous iodine is transported to the iodine absorption solvent 3 through a pipeline to form an iodine solution;

[0037] Step S4: collecting the mass of the iodine collecting tank 2 in real time by the balance 1;

[0038] Step S5: Calculate the iodine working medium flow rate in real time based on the data collected by the balance 1;

[0039] Step S6: After the test is completed, the iodine storage tank 13 is closed for heating, and the solenoid valve is closed after the reading of the balance 1 remains unchanged, the heating is stopped, and the pipeline lifter 5 is controlled to lift the pipeline so that the pipeline outlet is away from the iodine absorption solvent liquid surface.

[0040] Preferably, step S2 comprises: heating the iodine storage tank 13, the solenoid valve, the pressure sensor, the throttle 9 and the corresponding pipelines through the heating belt, and when the iodine storage tank 13 is heated to a preset temperature, measuring the gas pressure at the outlet of the iodine storage tank 13, and opening the solenoid valve after the pressure stabilizes.

[0041] Compared with the prior art, the present invention has the following beneficial effects:

[0042] 1. Compared with the existing method of calculating the flow rate by weighing the mass difference before and after the iodine storage tank is heated, the present invention can obtain the flow rate of iodine vapor under different working conditions in real time, thereby improving the measurement accuracy and efficiency;

[0043] 2. Compared with the closed iodine gaseous working medium flow measurement device, the present invention is simpler and can avoid the influence of stress caused by capillary heating on the measurement result, and has higher accuracy;

[0044] 3. During the test, the solid iodine is heated to gaseous iodine through the iodine working medium storage and supply module, and the gaseous iodine is transported to the iodine vapor adsorption solvent in the iodine collection tank. The adsorption solvent absorbs the iodine vapor and cools it at the same time, ensuring that the iodine vapor is completely dissolved in the adsorption solvent. By measuring the mass change of the iodine collection tank, the real-time flow rate of the iodine working medium can be calculated, completing the flow test and calibration of the iodine storage and supply system. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Other features, objects and advantages of the present invention will become more apparent from the detailed description of non-limiting embodiments made with reference to the following drawings:

[0046] Figure 1 This is a schematic diagram of the iodine working medium flow measurement device.

[0047] Figure 2 Schematic diagram of the iodine working fluid flow measurement method. DETAILED DESCRIPTION

[0048] The present invention is described in detail below in conjunction with specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but are not intended to limit the present invention in any form. It should be noted that, for those of ordinary skill in the art, several changes and improvements can also be made without departing from the concept of the present invention. These all belong to the protection scope of the present invention.

[0049] Example 1

[0050] According to an iodine vapor flow measurement device provided by the present invention, Figure 1 As shown, it includes two parts: a flow measurement module and an iodine storage and supply module;

[0051] The flow measurement module includes a balance 1, an iodine collecting tank 2, an iodine absorption solvent 3, a filter 4, a pipeline lifter 5, an exhaust valve 6, an on-off solenoid valve 7, a pressure sensor 8, and corresponding pipelines and heating cables of each component; wherein the balance 1 is used to weigh the mass of the collecting tank, and the weighing accuracy reaches 0.1 mg; the iodine collecting tank 2 is compatible with iodine and iodine absorption solvent 3, and is used to collect incoming iodine vapor. In order to prevent the pipeline extending into the iodine absorption solvent 3 from affecting the measurement result, the iodine collecting tank 2 is an open structure, and the open size is slightly larger than the diameter of the gas transport pipeline, and the pipeline extends into the iodine absorption solvent 3; the pipeline lifter 5 is used to control the pipeline to extend into and lift out the iodine absorption solvent; the pipeline outlet is equipped with an air bubble stone, and a filter is placed near the pipeline outlet to ensure the complete absorption of iodine vapor; the iodine absorption solvent 3 adopts iodine solvent A solvent with a large decomposition degree and a theoretical saturated vapor pressure of 0 is used to cool and absorb iodine vapor. Ionic liquid is used as the solvent, and the outlet pressure of iodine vapor is controlled by controlling the length of the pipeline extending into the iodine absorption solvent; the on-off solenoid valve is used to control the on-off of the gas path, and the exhaust valve is used to exhaust the air in the pipeline before the measurement starts; the pressure sensor is used to measure the iodine vapor pressure in the pipeline, which is used to calibrate the corresponding relationship between pressure and flow, and the range is 0-20kPa; among these components, the iodine collection tank 2, the filter 4, the on-off solenoid valve 7, the exhaust valve 6, the pressure sensor 8, the pipeline and other parts that are in direct contact with iodine vapor need to be made of materials compatible with iodine; the control and data acquisition of each component of the flow measurement module are realized by the controller, and the real-time flow of iodine vapor is calculated by the host computer software.

[0052] The iodine storage and supply module comprises an iodine storage tank 13, a pressure sensor 12, an exhaust valve 11, an on-off solenoid valve 10, a throttle 9 and corresponding pipelines and heating cables of each component; wherein the iodine storage tank 13 is used to place solid iodine; the pressure sensor 12 is used to measure the pressure of iodine vapor at the outlet of the iodine storage tank, and the range is 0-20 kPa; the exhaust valve 11 is used to exhaust the air in the pipeline and the storage tank before the measurement starts; the on-off solenoid valve 10 is used to control the on-off of the gas path; the throttle 9 is used to control the size of the iodine vapor flow rate, the throttle 9 is made of a stainless steel capillary tube with an inner diameter of about 0.5 mm, and a heating cable is wound on the capillary tube, and the flow rate is controlled by adjusting the temperature of the throttle; the above components are all made of materials compatible with iodine; the temperature control of the iodine storage and supply module and the on-off of the solenoid valve and the exhaust valve are realized by an external controller.

[0053] The iodine flow measurement module and the iodine storage and supply module are connected through pipelines.

[0054] According to a method for measuring iodine vapor flow provided by the present invention, Figure 2 As shown, including:

[0055] Step 1: Place the iodine vapor flow measurement device in a vacuum chamber and draw the vacuum degree to about 10Pa;

[0056] Step 2: Open the solenoid valve and exhaust valve of the iodine vapor measuring device to exhaust the air in the iodine storage and supply module and the flow measurement module into a vacuum;

[0057] Step 3: close the solenoid valve and the exhaust valve, control the pipeline lifter 5 to extend the pipeline into the iodine absorption solvent, heat the storage tank 13, the solenoid valves 7, 10, the pressure sensors 8, 12, the throttle 9 and the corresponding pipelines through the heating belt, heat the storage tank to 80°C, measure the gas pressure at the outlet of the iodine storage tank, open the solenoid valves 7, 10 after the pressure stabilizes, and the iodine vapor enters the iodine flow measurement module through the throttle;

[0058] Step 4: The iodine vapor enters the iodine absorption solvent 3 and dissolves to form an iodine solution. The mass of the iodine collection tank 2 is collected in real time by the balance 1. The flow rate of the iodine vapor is calculated in real time by the upper computer software, and the pressure readings of the pressure sensors 8 and 12 are recorded.

[0059] Step 5: After the measurement is completed, first turn off the tank heating, wait until the balance reading no longer changes, then close the solenoid valves 7 and 10, stop heating, and control the pipeline lifter to lift the iodine absorption solvent out of the pipeline to prevent the iodine absorption solvent from flowing back into the pipeline when the vacuum chamber is broken;

[0060] Step 6: After the temperature of the entire measuring device drops to room temperature, the vacuum chamber stops pumping air, breaks the vacuum, and takes out the device.

[0061] The above describes the specific embodiments of the present invention. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art can make various changes or modifications within the scope of the claims, which does not affect the essence of the present invention. In the absence of conflict, the embodiments of the present application and the features in the embodiments can be combined with each other arbitrarily.

Claims

1. An iodine vapor flow measurement device, characterized in that, include: Iodine working fluid flow measurement module and iodine working fluid storage and supply module; The iodine working medium flow measurement module and the iodine working medium storage and supply module are connected through a pipeline; The iodine working medium storage and supply module is used to heat the solid iodine working medium to a gaseous state, and transmit the iodine vapor to the iodine collecting tank (2) in the iodine working medium flow measurement module, and utilize the iodine absorption solvent (3) in the iodine collecting tank (2) to dissolve the iodine to achieve real-time flow measurement; The iodine working fluid flow measurement module is placed in a vacuum environment.

2. The iodine vapor flow measuring device according to claim 1, characterized in that: The iodine working medium storage and supply module comprises: a throttle (9), an on-off solenoid valve (10), an exhaust valve (11), a pressure sensor (12) and an iodine storage tank (13); The iodine storage tank (13) in the iodine working medium storage and supply module is connected to the iodine collection tank (2) in the iodine working medium flow measurement module through a pipeline; In the iodine working medium storage and supply module, the throttle (9), the on-off solenoid valve (10), the exhaust valve (11) and the pressure sensor (12) are provided on the pipeline connecting the iodine storage tank (13) and the iodine collection tank (2); The iodine storage box (13) is used to store iodine; The pressure sensor (12) is used to measure the iodine vapor pressure at the outlet of the iodine storage tank (13); The exhaust valve (11) is used to exhaust the air in the iodine storage tank (13) and the pipeline; The on-off solenoid valve (10) is used to control the on-off of the pipeline of the iodine working medium storage and supply module; The throttle (9) is used to control the iodine flow rate.

3. The iodine vapor flow measuring device according to claim 1, characterized in that: The iodine working medium flow measurement module comprises: an exhaust valve (6), an on-off solenoid valve (7), and a pressure sensor (8); The iodine collecting tank (2) in the iodine working medium flow measurement module is connected to the iodine storage tank (13) in the iodine working medium storage and supply module through a pipeline; In the iodine working medium flow measurement module, the exhaust valve (6), the on-off solenoid valve (7) and the pressure sensor (8) are provided on a pipeline connecting the iodine collecting tank (2) and the iodine storage tank (13); The exhaust valve (6) is used to exhaust air in the transport pipeline; The on-off solenoid valve (7) is used to control the on-off of the pipeline; The pressure sensor (8) is used to measure the gas pressure in the pipeline.

4. The iodine vapor flow measuring device according to claim 3, characterized in that: The iodine working medium flow measurement module further comprises a balance (1); The iodine collecting tank (2) containing the iodine absorbing solvent (3) is placed on the balance (1), and the mass of iodine absorbed in real time is weighed using the balance (1).

5. The iodine vapor flow measuring device according to claim 3, characterized in that: The iodine working medium flow measurement module also includes a filter screen (4) and an air stone; The filter screen (4) is arranged at the port extending into the pipeline of the iodine absorption solvent (3), and the bubble stone is arranged at the port of the pipeline of the iodine absorption solvent (3) to ensure that the iodine vapor is fully absorbed.

6. The iodine vapor flow measurement device according to claim 3, characterized in that: The iodine working medium flow measurement module further comprises a pipeline lifter (5); The pipeline lifter (5) is arranged on the pipeline extending into the iodine absorbing solvent (3) and is used to control the depth of the pipeline extending into the iodine absorbing solvent (5).

7. The iodine vapor flow measurement device according to claim 1, characterized in that: The opening diameter of the iodine collecting tank (2) is larger than the diameter of the pipeline extending into the iodine absorbing solvent (3), and meets the preset requirements.

8. The iodine vapor flow measurement device according to claim 1, characterized in that: The iodine absorption solvent (3) is a solvent with an iodine solubility greater than a preset value and a theoretical saturated vapor pressure of 0, which is used for cooling and absorbing iodine vapor, and an ionic liquid is used as the solvent.

9. A method for measuring iodine vapor flow rate, characterized in that: The iodine vapor flow measurement device according to any one of claims 1 to 8 is used to perform the following steps: Step S1: opening the on-off solenoid valve and the exhaust valve in the iodine working medium flow measurement module and the iodine working medium storage and supply module to exhaust the air in the iodine working medium flow measurement module and the iodine working medium storage and supply module into a vacuum; Step S2: closing the exhaust valve and the solenoid valve, controlling the pipeline lifter (5) to extend the pipeline into the iodine absorption solvent (3), heating the iodine working medium flow measurement module and the iodine working medium storage and supply module, and heating the solid iodine in the iodine working medium storage and supply module to gaseous iodine; Step S3: opening the solenoid valve, and the gaseous iodine is transported to the iodine absorbing solvent (3) through a pipeline to form an iodine solution; Step S4: collecting the mass of the iodine collection tank (2) in real time by means of the balance (1); Step S5: Calculating the iodine working medium flow rate in real time based on the data collected by the balance (1); Step S6: After the test is completed, the iodine storage box (13) is first closed for heating, and after the reading of the balance (1) remains unchanged, the solenoid valve is closed, the heating is stopped, and the pipeline lifter (5) is controlled to lift the pipeline so that the pipeline outlet is away from the iodine absorption solvent liquid surface.

10. The iodine vapor flow measurement method according to claim 9, characterized in that: The step S2 comprises: heating the iodine storage tank (13), the solenoid valve, the pressure sensor, the throttle (9) and the corresponding pipelines through the heating belt; when the iodine storage tank (13) is heated to a preset temperature, measuring the gas pressure at the outlet of the iodine storage tank (13); and opening the solenoid valve after the pressure is stabilized.

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