Calibrating device for hydrogen flow meter

Abstract

The utility model provides a hydrogen flow meter calibration device which comprises a gas supply pipeline, a stagnation container, a nozzle module and an exhaust module which are sequentially arranged, and the gas supply pipeline is communicated with a gas pipeline of a calibrated module provided with a calibrated hydrogen flow meter. The hydrogen flow meter calibration device further comprises a measuring module and a temperature adjusting module, the measuring module is at least used for detecting the pressure and the temperature in the stagnation container, and the temperature adjusting module adjusts the internal temperature of the stagnation container through liquid bath temperature adjustment or electric temperature adjustment. The nozzle module comprises a sonic nozzle arranged in the stagnation container, and the sonic nozzle is used for measuring the flow of hydrogen flowing through the nozzle module. By adopting the scheme, the problems that in the prior art, when an air source with pressure enters the stagnation container, the temperature in the stagnation container is reduced, the time required for the temperature of the air source in the stagnation container to be stable becomes long, and the calibration efficiency is influenced can be solved.

Description

Technical Field

[0001] The utility model relates to the technical field of hydrogen flowmeter calibration, and particularly relates to a hydrogen flowmeter calibration device. Background Art

[0002] With the development of the hydrogen energy industry, hydrogen flowmeters are widely used in fields such as hydrogen transportation, hydrogen energy storage, and hydrogen industry. According to relevant regulations, the (hydrogen) flowmeters used in equipment should be calibrated regularly during use to ensure their reliability.

[0003] In the prior art, a gas flow device based on the critical flow Venturi nozzle method is generally used for calibration work. The gas flow device at least includes a stagnation container and a sonic nozzle module. During calibration, a pressurized gas source (hydrogen) enters the stagnation container and reaches a stable pressure and temperature state inside the stagnation container. Then, the gas source in the stagnation container is discharged through the sonic nozzle module. The actual gas source mass flow rate used as calibration data is obtained through the gas source flow rate detected by the sonic nozzle, the pressure (also called stagnation pressure) and temperature (also called stagnation temperature) inside the stagnation container, and the inherent characteristic parameters of the gas source. Its structure is simple, the performance is stable, the accuracy is high, and the maintenance is convenient.

[0004] However, since the gas expands and absorbs heat when a pressurized gas suddenly enters a large space, in the actual calibration process of the calibration device provided by the prior art solution, when the pressurized gas source flows into the stagnation container, the ambient temperature inside the stagnation container will decrease, which will in turn cause the time required for the temperature inside the stagnation container to reach stability (stagnation temperature) to become longer, affecting the calibration efficiency. Summary of the Utility Model

[0005] The utility model provides a hydrogen flowmeter calibration device to solve the problem in the prior art that when a pressurized gas source enters the stagnation container, the temperature inside the stagnation container will decrease, resulting in a longer time for the gas source temperature inside the stagnation container to reach stability and affecting the calibration efficiency.

[0006] To solve the above problems, the utility model provides a hydrogen flowmeter calibration device. The hydrogen flowmeter calibration device includes a gas supply pipeline, a stagnation container, a nozzle module, and an exhaust module arranged in sequence. The gas supply pipeline is communicated with the gas pipeline of the calibrated module provided with the calibrated hydrogen flowmeter. The hydrogen flowmeter calibration device further includes a measurement module and a temperature adjustment module. The measurement module is at least used to detect the pressure and temperature inside the stagnation container. The temperature adjustment module adjusts the internal temperature of the stagnation container through liquid bath temperature adjustment or electric temperature adjustment. The nozzle module includes a sonic nozzle arranged inside the stagnation container, and the sonic nozzle is used to measure the hydrogen flow rate flowing through the nozzle module.

[0007] Further, the temperature regulation module regulates the internal temperature of the stagnation container through liquid bath temperature regulation. The liquid bath temperature regulation is oil bath temperature regulation. The temperature regulation module includes an oil bath machine and an oil bath container. A liquid bath cavity for placing the stagnation container is formed inside the oil bath container. The liquid phase outlet of the oil bath machine is communicated with the liquid phase inlet of the oil bath container to supply the oil liquid required for oil bath temperature regulation to the liquid bath cavity.

[0008] Further, the liquid phase outlet of the oil bath machine is communicated with the liquid phase inlet of the oil bath machine to recover the oil liquid in the liquid bath cavity. Wherein, the liquid phase outlet of the oil bath container is located at the bottom of the oil bath container, and the liquid phase inlet of the oil bath container is located at the top of the oil bath container.

[0009] Further, the measurement module includes a first temperature sensor and a first pressure sensor. The first temperature sensor and the first pressure sensor are respectively used to detect the temperature and pressure inside the stagnation container.

[0010] Further, the hydrogen flowmeter calibration device further includes a pressure controller. The pressure controller is arranged on the gas supply pipeline to regulate the air flow pressure flowing through the gas supply pipeline.

[0011] Further, the measurement module includes a second temperature sensor and a second pressure sensor. The second temperature sensor is used to detect the temperature inside the gas supply pipeline, and the second pressure sensor is used to detect the pressure inside the gas supply pipeline. The detection positions of the second temperature sensor and the second pressure sensor are between the pressure controller and the stagnation container.

[0012] Further, the measurement module further includes a third pressure sensor. The third pressure sensor is used to detect the pressure inside the exhaust module.

[0013] Further, the nozzle module includes a sonic nozzle, a nozzle pipeline and a nozzle switching valve. The sonic nozzle is arranged inside the stagnation container and communicated with the stagnation container. The sonic nozzle is communicated with the exhaust module through the nozzle pipeline. The nozzle switching valve is arranged on the nozzle pipeline and outside the stagnation container to control the fluid flow rate flowing through the nozzle module. Wherein, in the case where there are multiple nozzle modules, the multiple nozzle modules are arranged in parallel.

[0014] Further, the exhaust module includes a vacuum container, an exhaust pipeline and a vacuum pump. The nozzle module is communicated with the vacuum container. The vacuum container discharges the internal gas through the exhaust pipeline. The vacuum pump is arranged on the exhaust pipeline.

[0015] Further, the hydrogen flowmeter calibration device further includes a flow regulating valve group and an adapter. The gas pipeline of the calibrated module provided with the calibrated hydrogen flowmeter is communicated with the gas supply pipeline through the adapter. The flow regulating valve group is arranged on the gas supply pipeline to control the gas flow rate flowing through the gas supply pipeline to the stagnation container.

[0016] Applying the technical solution of the present utility model, a hydrogen flowmeter calibration device is provided. The hydrogen flowmeter calibration device includes a gas supply pipeline, a stagnation container, a nozzle module, and an exhaust module arranged in sequence. The gas supply pipeline is communicated with the gas pipeline of the calibrated module provided with the calibrated hydrogen flowmeter. The hydrogen flowmeter calibration device further includes a measurement module and a temperature adjustment module. The measurement module is at least used to detect the pressure and temperature inside the stagnation container. The temperature adjustment module adjusts the internal temperature of the stagnation container by liquid bath temperature adjustment or electric temperature adjustment; the nozzle module includes a sonic nozzle arranged inside the stagnation container, and the sonic nozzle is used to measure the hydrogen flow rate flowing through the nozzle module.

[0017] The calibration process of this solution includes: The hydrogen gas source first flows through the hydrogen flowmeter, and the hydrogen flowmeter can directly measure the mass flow rate of the flowing hydrogen. This mass flow rate is the object to be calibrated, that is, the calibrated mass flow rate; then the hydrogen gas source enters the stagnation container under pressure through the gas supply pipeline. As the hydrogen gas source enters, the inside of the stagnation container gradually reaches a state of stable pressure and temperature (the pressure and temperature at this time are the stagnation pressure and stagnation temperature respectively). Then, control the hydrogen gas in the stagnation container to flow through the calibrated standard module and finally discharge from the exhaust module. During the process of the hydrogen gas source flowing through the nozzle module, the total amount of hydrogen flowing through the calibrated module can be measured by the sonic nozzle. Combining the total amount of hydrogen flowing through the calibrated module, the stagnation pressure inside the stagnation container measured by the measurement module, the stagnation temperature inside the stagnation container measured by the measurement module, and the inherent characteristic parameters of hydrogen gas, etc., the actual hydrogen mass flow rate, that is, the actual mass flow rate, can be calculated. By comparing the actual mass flow rate with the calibrated mass flow rate, it can be judged whether the hydrogen flowmeter needs to be calibrated and the required calibration value can be obtained. Among them, this solution realizes the rapid adjustment (heating) of the internal temperature of the stagnation container through the temperature adjustment module, avoiding the situation that the ambient temperature inside the stagnation container will decrease when the pressurized hydrogen gas source flows into the stagnation container, which will in turn lead to a longer time required for the inside of the stagnation container to reach the stagnation temperature, shortening the time required for the inside of the stagnation container to reach the stable stagnation temperature and improving the calibration efficiency. Further, compared with the situation where a constant temperature tank and other devices that use high-temperature gas to heat the stagnation container are mostly used in the related technology, the liquid bath heating method or the electric heating method adopted in this solution is more conducive to the rapid increase of temperature, which is conducive to further shortening the time required for the inside of the stagnation container to reach the stable stagnation temperature. Description of the Drawings

[0018] The specification drawings forming a part of this application are used to provide a further understanding of the present utility model. The schematic embodiments of the present utility model and their descriptions are used to explain the present utility model and do not constitute an improper limitation to the present utility model. In the drawings:

[0019] Figure 1 The structural schematic diagram of the hydrogen flowmeter calibration device provided by the embodiment of the present utility model is shown.

[0020] Among them, the above-mentioned drawings include the following reference numerals:

[0021] 10. Gas supply pipeline;

[0022] 20. Stagnation container;

[0023] 30. Nozzle module; 31. Sonic nozzle; 32. Nozzle switching valve; 33. Nozzle pipeline;

[0024] 40. Exhaust module; 41. Vacuum container; 42. Exhaust pipeline; 43. Vacuum pump;

[0025] 50. Module to be calibrated;

[0026] 60. Measurement module; 61. First pressure sensor; 62. First temperature sensor; 63. Second pressure sensor; 64. Second temperature sensor; 65. Third pressure sensor;

[0027] 70. Temperature regulation module; 701. Liquid bath chamber; 71. Oil bath machine; 72. Oil bath container;

[0028] 80. Pressure controller;

[0029] 90. Flow regulating valve group; 91. Flow control valve; 92. Gas supply switching valve;

[0030] 100. Adapter joint. Detailed implementation manners

[0031] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and in no way restrictive of the present invention and its application or use. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0032] Such as Figure 1As shown in the figure, an embodiment of the present utility model provides a hydrogen flowmeter calibration device. The hydrogen flowmeter calibration device includes a gas supply pipeline 10, a stagnation container 20, a nozzle module 30, and an exhaust module 40 arranged in sequence. The gas supply pipeline 10 is connected to the gas pipeline of the calibrated module 50 where the hydrogen flowmeter to be calibrated is provided. The hydrogen flowmeter calibration device further includes a measurement module 60 and a temperature adjustment module 70. The measurement module 60 is at least used to detect the pressure and temperature inside the stagnation container 20. The temperature adjustment module 70 adjusts the internal temperature of the stagnation container 20 through liquid bath temperature control or electric temperature control. The nozzle module 30 includes a sonic nozzle 31 arranged inside the stagnation container 20, and the sonic nozzle 31 is used to measure the hydrogen flow rate flowing through the nozzle module 30.

[0033] The calibration process of this embodiment includes: The hydrogen gas source first flows through the hydrogen flowmeter. The hydrogen flowmeter can directly measure the mass flow rate of the flowing hydrogen, and this mass flow rate is the object to be calibrated, that is, the mass flow rate to be calibrated. Then, the hydrogen gas source enters the stagnation container 20 under pressure through the gas supply pipeline 10. The inside of the stagnation container 20 gradually reaches a state of stable pressure and temperature (the pressure and temperature at this time are the stagnation pressure and stagnation temperature respectively) as the hydrogen gas source enters. Then, it is controlled that the hydrogen gas in the stagnation container 20 flows through the calibrated standard module and finally discharges from the exhaust module 40. During the process of the hydrogen gas source flowing through the nozzle module 30, the total amount of hydrogen flowing through the calibrated module can be measured by the sonic nozzle 31. Combining the total amount of hydrogen flowing through the calibrated module, the stagnation pressure inside the stagnation container 20 measured by the measurement module 60, the stagnation temperature inside the stagnation container 20 measured by the measurement module 60, and the inherent characteristic parameters of hydrogen gas, etc., the actual hydrogen mass flow rate (the method in GB / T 21188-2007 "Measurement of Gas Flow Rate by Critical Flow Venturi Nozzles" can be referred to) can be calculated, that is, the actual mass flow rate. By comparing the actual mass flow rate and the mass flow rate to be calibrated, it can be judged whether the hydrogen flowmeter needs to be calibrated and the required calibration value can be obtained. Among them, in this embodiment, the temperature adjustment module 70 is used to quickly adjust the internal temperature of the stagnation container 20 (heating), avoiding the situation that the ambient temperature inside the stagnation container 20 will decrease when the pressurized hydrogen gas source flows into the stagnation container 20, which will in turn lead to a longer time required for the inside of the stagnation container 20 to reach the stagnation temperature, shortening the time required for the inside of the stagnation container 20 to reach the stable stagnation temperature and improving the calibration efficiency. Further, compared with the situation in the related art where a constant temperature tank and other devices are mostly used to heat the stagnation container 20 with high-temperature gas, the liquid bath heating method or electric heating method adopted in this embodiment is more conducive to quickly increasing the temperature, which is conducive to further shortening the time required for the inside of the stagnation container 20 to reach the stable stagnation temperature.

[0034] It should be noted that the module 50 to be calibrated includes a hydrogen flowmeter to be calibrated. In this embodiment, the hydrogen flowmeter calibration device detects and calibrates one hydrogen flowmeter to be calibrated at a time. It can be understood that the module 50 to be calibrated may also include components for controlling fluid flow, such as regulating valves and pumps, and other components for adjusting the gas pipeline environment (temperature or pressure) according to actual situations. All components, together with the hydrogen flowmeter to be calibrated and the gas pipeline, form the module 50 to be calibrated.

[0035] As Figure 1 shown, in this embodiment, the temperature regulation module 70 adjusts the internal temperature of the stagnation container 20 through liquid bath temperature regulation, and the liquid bath temperature regulation is oil bath temperature regulation (oil bath heating). Specifically, the temperature regulation module 70 includes an oil bath machine 71 and an oil bath container 72. An oil bath cavity 701 for placing the stagnation container 20 is formed inside the oil bath container 72. The liquid phase outlet of the oil bath machine 71 is communicated with the liquid phase inlet of the oil bath container 72 to supply the oil required for oil bath temperature regulation to the oil bath cavity 701. With such a setting, it is convenient to provide a continuous and stable oil supply for the oil bath container 72 by setting the oil bath machine 71, ensuring the stability and reliability of the temperature regulation (heating) of the stagnation container 20.

[0036] It can be understood that the liquid bath temperature regulation can also be other liquid bath temperature regulation methods such as water bath temperature regulation (water bath heating).

[0037] Among them, in other embodiments not shown in the figure, the temperature regulation module 70 adjusts the internal temperature of the stagnation container 20 by means of electric temperature regulation (electric heating), heating the inside of the stagnation container 20 by converting electrical energy into heat energy, and the form can be resistive, inductive, arc type, etc.

[0038] Furthermore, the liquid phase outlet of the oil bath container 72 is communicated with the liquid phase inlet of the oil bath machine 71 to recycle the oil in the oil bath cavity 701; among them, the liquid phase outlet of the oil bath container 72 is located at the bottom of the oil bath container 72, and the liquid phase inlet of the oil bath container 72 is located at the top of the oil bath container 72. With such a setting, the recycling of the oil in the oil bath cavity 701 can be realized. It can be understood that the oil bath machine 71 can reheat the recycled oil so that it enters the oil bath cavity 701 again at a high temperature to heat the stagnation container 20.

[0039] In this embodiment, the measurement module 60 includes a first temperature sensor 62 and a first pressure sensor 61. The first temperature sensor 62 and the first pressure sensor 61 are respectively used to detect the temperature and pressure inside the stagnation container 20. It can be understood that the first temperature sensor 62 and the first pressure sensor 61 are also used to determine whether the stagnation container 20 reaches a state of stable pressure and temperature. It should be noted that the first temperature sensor 62 and the first pressure sensor 61 are mainly used to measure the stagnation temperature and stagnation pressure inside the stagnation container 20 after the pressure and temperature are stabilized, so as to calculate the actual mass flow rate of the hydrogen gas source flowing through the nozzle module.

[0040] Among them, in the flowmeter calibration work, the pressure fluctuation of the gas in the pipeline will, on the one hand, affect the gas stabilization time and calibration efficiency; on the other hand, if the pressure fluctuation is too large, it will also cause device failures and damages, affecting the service life of the device. In order to solve the problem that the existing flowmeter calibration device cannot effectively adjust and control the gas pressure in the pipeline and the internal gas pressure of the pipeline is unstable due to various situations (such as the gas pressure fluctuation in the pipeline caused by the unstable pressure of the gas source itself, the gas pressure fluctuation in the pipeline caused by unreasonable pipeline design, the gas pressure fluctuation caused by the change of the gas velocity in the pipeline, etc.) during the flowmeter calibration work, the hydrogen flowmeter calibration device in this embodiment further includes a pressure controller 80. The pressure controller 80 is arranged on the gas supply pipeline 10 to adjust the air flow pressure flowing through the gas supply pipeline 10. With this setting, the pressure of the hydrogen gas source flowing through the gas supply pipeline 10 can be adjusted during the calibration process through the pressure controller 80, avoiding situations where pressure fluctuations affect the calibration efficiency, controlling the pressure range of the hydrogen gas source, and being beneficial to improving the calibration work efficiency and extending the service life of the device.

[0041] Furthermore, the measurement module 60 includes a second temperature sensor 64 and a second pressure sensor 63. The second temperature sensor 64 is used to detect the temperature inside the gas supply pipeline 10, and the second pressure sensor 63 is used to detect the pressure inside the gas supply pipeline 10. The detection positions of the second temperature sensor 64 and the second pressure sensor 63 are located between the pressure controller 80 and the stagnation container 20. In this embodiment, the pressure and temperature inside the gas supply pipeline 10 are detected through the second pressure sensor 63 and the second temperature sensor 64, so as to determine whether the hydrogen gas source in the pipeline reaches a state of stable pressure and temperature. On the other hand, it is possible to judge whether to turn on the temperature adjustment module 70 by comparing the first temperature sensor 62 and the second temperature sensor 64.

[0042] Among them, the pressure and temperature detected by the second pressure sensor 63 and the second temperature sensor 64 are used as the standard ambient pressure and the standard ambient temperature respectively. The stagnation temperature after stabilization is slightly greater than the standard ambient temperature, and the stagnation temperature generally rises through the characteristic parameters of the hydrogen gas source itself, rather than being achieved by oil bath heating. During the calibration process, when the pressurized hydrogen gas source enters the stagnation container 20, the temperature inside the stagnation container 20 will drop below the standard ambient temperature. Due to the temperature reduction and the slow rise of the gas itself temperature, it is difficult for the temperature inside the stagnation container 20 to quickly reach a stable state. Through the temperature adjustment module 70, the temperature of the stagnation container 20 can be quickly restored and maintained at the standard ambient temperature, reducing the time required for the temperature inside the stagnation container 20 to rise to the stagnation temperature.

[0043] The nozzle module 30 includes a sonic nozzle 31, a nozzle pipeline 33, and a nozzle switching valve 32. The sonic nozzle 31 is arranged inside the stagnation container 20 and communicates with the stagnation container 20. The sonic nozzle 31 communicates with the exhaust module 40 through the nozzle pipeline 33. The nozzle switching valve 32 is arranged on the nozzle pipeline 33 and is located outside the stagnation container 20 to control the fluid flow rate flowing through the nozzle module 30. Specifically, there can be multiple nozzle modules 30. When there are multiple nozzle modules 30, the multiple nozzle modules 30 are arranged in parallel. This setting facilitates the operator to open the corresponding number of nozzle switching valves 32 according to the actual flow rate situation for reliable measurement of the flowing hydrogen gas source flow rate, ensuring the reliability and measurable range of the measurement.

[0044] In this embodiment, there are five nozzle modules 30, and the five nozzle modules 30 are spaced apart along the height direction of the stagnation container 20. Both ends of any one nozzle pipeline 33 respectively extend to the inside of the stagnation container 20 and the outside of the oil bath container 72 covering the outer periphery of the stagnation container 20. The five sonic nozzles 31 are all arranged inside the stagnation container 20 and are respectively communicated with one end of the five nozzle pipelines 33 extending into the stagnation container 20. The five nozzle switching valves 32 are all located outside the oil bath container 72 and are respectively arranged on the five nozzle pipelines 33. The ends of the five nozzle pipelines 33 protruding from the oil bath container 72 are all communicated with the exhaust module 40.

[0045] As Figure 1 shown, the exhaust module 40 includes a vacuum container 41, an exhaust pipeline 42, and a vacuum pump 43. The ends of the five nozzle pipelines 33 protruding from the oil bath container 72 are all communicated with the vacuum container 41. The vacuum container 41 discharges the internal gas through the exhaust pipeline 42. The vacuum pump 43 is arranged on the exhaust pipeline 42. The measurement module 60 further includes a third pressure sensor 65, and the third pressure sensor 65 is used to detect the pressure inside the exhaust module 40 (the vacuum container 41).

[0046] In this embodiment, after determining the number of sonic nozzles 31 to be used according to the actual flow rate, start the vacuum pump 43 to discharge the gas inside the vacuum container 41, so as to reduce the pressure of the gas to be tested to a negative pressure. Detect the pressure value of the exhaust module 40 through the third pressure sensor 65 to ensure that the allowable pressure downstream of the sonic nozzle 31 meets the critical backpressure ratio, so that the gas flow velocity at the throat of the sonic nozzle 31 reaches the critical value. During the process that the gas flow velocity at the throat of the sonic nozzle 31 reaches the critical value, the entry of the pressurized gas into the stagnation container 20 will cause the temperature of the internal environment of the stagnation container 20 to drop below the standard ambient temperature. It can be judged whether to use the temperature adjustment module 70 by analyzing the values of the first temperature sensor 62 and the second temperature sensor 64.

[0047] As Figure 1 shown, the hydrogen flowmeter calibration device further includes a flow regulating valve group 90 and an adapter joint 100. The gas pipeline of the calibrated module 50 provided with the calibrated hydrogen flowmeter is connected to the gas supply pipeline 10 through the adapter joint 100. The flow regulating valve group 90 is arranged on the gas supply pipeline 10 to control the gas flow rate flowing through the gas supply pipeline 10 to the stagnation container 20.

[0048] In this embodiment, the flow regulating valve group 90 includes a flow control valve 91 and a gas supply switch valve 92. The flow control valve is arranged between the adapter joint 100 and the pressure controller 80. The gas supply switch valve 92 is arranged between the pressure controller 80 and the stagnation container 20 and is located outside the oil bath container 72. The gas supply switch valve 92 is used to control the on-off of the gas supply pipeline 10 and the stagnation container 20. The flow control valve 91 is used to control the flow rate (which can be 0) of the hydrogen gas source provided by the calibrated module 50 into the gas supply pipeline 10. Among them, the number of sonic nozzles 31 required for measurement is judged according to the flow rate controlled by the flow control valve 91.

[0049] In summary, the present utility model provides a hydrogen flowmeter calibration device. The gas pipeline of the calibrated module 50 provided with the hydrogen flowmeter to be calibrated is connected to the gas supply pipeline 10 of the hydrogen flowmeter calibration device provided by the present utility model through the adapter 100. After connecting the hydrogen flowmeter to be calibrated, the gas supply switch valve 92 is opened, and the flow rate is controlled by the flow control valve 91 to gradually increase the gas flow rate. The air flow pressure is regulated by the pressure controller 80 to keep it stable, and the second pressure sensor 63 is used to monitor and determine whether the air flow pressure is stable. The number of sonic nozzles 31 required for measurement is determined by judging the flow rate controlled by the flow control valve 91, and then the corresponding number of sonic nozzles 31 is opened through the nozzle switch valve 32 for measuring the flow rate value. After determining the number of sonic nozzles 31 used, the vacuum pump 43 is started to reduce the pressure of the gas to be tested to a negative pressure, and the pressure value in the vacuum container 41 is detected by the third pressure sensor 65 to ensure that the allowable pressure downstream of the sonic nozzle 31 meets the critical backpressure ratio, so that the gas flow velocity at the throat of the sonic nozzle 31 reaches the critical value. During the process that the gas flow velocity at the throat of the sonic nozzle 31 reaches the critical value, the pressurized gas enters the stagnation container 20, resulting in the temperature of the internal environment of the stagnation container 20 dropping below the standard ambient temperature. At this time, it can be judged whether to use the temperature adjustment module 70 by analyzing the values of the first temperature sensor 62 and the second temperature sensor 64. When it is necessary to use the temperature adjustment module 70, the oil bath machine 71 is started to circulate and transport hot oil into the liquid bath cavity 701 to regulate the temperature in the stagnation container 20. After the temperature reaches the standard ambient temperature, the oil bath machine 71 is turned off to stop heating. Finally, the total amount of hydrogen flowing through the calibrated module is measured by the sonic nozzle 31. Combining the total amount of hydrogen flowing through the calibrated module, the stagnation pressure inside the stagnation container 20 measured by the measurement module 60, the stagnation temperature inside the stagnation container 20 measured by the measurement module 60, and the inherent characteristic parameters of hydrogen, etc., the actual hydrogen mass flow rate (i.e., the actual mass flow rate) can be calculated. Since the gas continuously flows through the sonic nozzle 31 (the number of sonic nozzles 31 used can be adjusted adaptively according to the flow rate) and the hydrogen flowmeter to be calibrated within the same time interval, according to the law of conservation of mass, the mass flow rate through the sonic nozzle 31 and the mass flow rate of the hydrogen flowmeter to be calibrated should be the same. By comparing the measured mass flow rate of the hydrogen flowmeter to be calibrated and the calculated actual mass flow rate, the metering performance of the hydrogen flowmeter to be calibrated can be determined, thereby achieving accurate calibration of the hydrogen flowmeter to be calibrated. The hydrogen flowmeter calibration device provided in this embodiment can quickly regulate the pressure and temperature of the gas in the pipeline, thereby improving and ensuring the efficiency of the calibration work and the effectiveness of the calibration device.

[0050] It can be understood that the valves in the hydrogen flowmeter calibration device provided by the present utility model are all default closed unless stated to be opened.

[0051] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they specify the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0052] Unless otherwise specifically stated, the relative arrangements of components and steps, numerical expressions, and numerical values set forth in these embodiments do not limit the scope of the present invention. At the same time, it should be understood that, for the sake of convenience of description, the dimensions of the various parts shown in the drawings are not drawn in actual proportional relationships. Technologies, methods, and devices known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, the said technologies, methods, and devices should be regarded as part of the authorized specification. In all the examples shown and discussed herein, any specific value should be construed as merely exemplary and not as a limitation. Therefore, other examples of the exemplary embodiments may have different values. It should be noted that like reference numerals and letters denote like items in the following drawings, and thus, once an item is defined in one drawing, further discussion thereof is not required in subsequent drawings.

[0053] In the description of the present invention, it should be understood that the orientation or positional relationships indicated by orientation words such as "front, rear, upper, lower, left, right", "lateral, vertical, perpendicular, horizontal", and "top, bottom" are generally based on the orientation or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description. Without contrary description, these orientation words do not indicate and imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and thus should not be construed as limiting the protection scope of the present invention; the orientation words "inside, outside" refer to the inside and outside relative to the contour of each component itself.

[0054] For ease of description, spatial relative terms such as "above", "over", "on the upper surface", "upper" etc. may be used herein to describe the spatial positional relationship of one device or feature to other devices or features as shown in the figures. It should be understood that the spatial relative terms are intended to encompass different orientations in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is inverted, a device described as "above" or "over" other devices or structures will then be positioned "below" or "under" the other devices or structures. Thus, the exemplary term "above" can include both the orientations of "above" and "below". The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the corresponding explanations for the spatial relative descriptions used herein will be made accordingly.

[0055] In addition, it should be noted that the use of terms such as "first" and "second" to define components is only for the convenience of differentiating the corresponding components. Without additional statements, the above terms have no special meanings, and thus should not be construed as limiting the protection scope of the present utility model.

[0056] The above are only the preferred embodiments of the present utility model and are not used to limit the present utility model. For those skilled in the art, the present utility model can have various modifications and variations. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present utility model shall be included within the protection scope of the present utility model.

Claims

1. A hydrogen flowmeter calibration device, characterized in that, The hydrogen flowmeter calibration device includes a gas supply pipeline (10), a stagnation container (20), a nozzle module (30), and an exhaust module (40) arranged in sequence. The gas supply pipeline (10) is communicated with the gas pipeline of a calibrated module (50) where a hydrogen flowmeter to be calibrated is arranged. The hydrogen flowmeter calibration device further includes a measurement module (60) and a temperature adjustment module (70). The measurement module (60) is at least used to detect the pressure and temperature inside the stagnation container (20). The temperature adjustment module (70) adjusts the internal temperature of the stagnation container (20) by liquid bath temperature adjustment or electric temperature adjustment. The nozzle module (30) includes a sonic nozzle (31) arranged inside the stagnation container (20), and the sonic nozzle (31) is used to measure the hydrogen flow rate flowing through the nozzle module (30).

2. The hydrogen flowmeter calibration device according to claim 1, wherein The temperature adjustment module (70) adjusts the internal temperature of the stagnation container (20) by liquid bath temperature adjustment. The liquid bath temperature adjustment is oil bath temperature adjustment. The temperature adjustment module (70) includes an oil bath machine (71) and an oil bath container (72). An internal liquid bath cavity (701) for placing the stagnation container (20) is formed inside the oil bath container (72). The liquid phase outlet of the oil bath machine (71) is communicated with the liquid phase inlet of the oil bath container (72) to supply the oil liquid required for oil bath temperature adjustment to the liquid bath cavity (701).

3. The hydrogen flowmeter calibration device according to claim 2, characterized in that, The liquid phase outlet of the oil bath container (72) is communicated with the liquid phase inlet of the oil bath machine (71) to recover the oil liquid in the liquid bath cavity (701). Among them, the liquid phase outlet of the oil bath container (72) is located at the bottom of the oil bath container (72), and the liquid phase inlet of the oil bath container (72) is located at the top of the oil bath container (72).

4. The hydrogen flowmeter calibration device according to claim 1, characterized in that, The measurement module (60) includes a first temperature sensor (62) and a first pressure sensor (61). The first temperature sensor (62) and the first pressure sensor (61) are respectively used to detect the temperature and pressure inside the stagnation container (20).

5. The hydrogen flowmeter calibration device according to claim 1, characterized in that, The hydrogen flowmeter calibration device further includes a pressure controller (80). The pressure controller (80) is arranged on the gas supply pipeline (10) to adjust the air flow pressure flowing through the gas supply pipeline (10).

6. The hydrogen flowmeter calibration device according to claim 5, characterized in that, The measurement module (60) includes a second temperature sensor (64) and a second pressure sensor (63). The second temperature sensor (64) is used to detect the temperature inside the gas supply pipeline (10), and the second pressure sensor (63) is used to detect the pressure inside the gas supply pipeline (10). The detection positions of the second temperature sensor (64) and the second pressure sensor (63) are located between the pressure controller (80) and the stagnation container (20).

7. The hydrogen flowmeter calibration device according to claim 1, characterized in that The measurement module (60) further includes a third pressure sensor (65). The third pressure sensor (65) is used to detect the pressure inside the exhaust module (40).

8. The hydrogen flowmeter calibration device according to claim 1, characterized in that The nozzle module (30) includes the sonic nozzle (31), a nozzle pipeline (33), and a nozzle switching valve (32). The sonic nozzle (31) is disposed within the stagnation container (20) and is in communication with the stagnation container (20). The sonic nozzle (31) is in communication with the exhaust module (40) through the nozzle pipeline (33). The nozzle switching valve (32) is disposed on the nozzle pipeline (33) and outside the stagnation container (20) to control the fluid flow rate through the nozzle module (30). Wherein, when there are multiple nozzle modules (30), the multiple nozzle modules (30) are arranged in parallel.

9. The hydrogen flowmeter calibration device according to claim 1, wherein The exhaust module (40) includes a vacuum container (41), an exhaust pipeline (42), and a vacuum pump (43). The nozzle module (30) is in communication with the vacuum container (41). The vacuum container (41) discharges the internal gas through the exhaust pipeline (42). The vacuum pump (43) is disposed on the exhaust pipeline (42).

10. The hydrogen flowmeter calibration device according to claim 1, characterized in that The hydrogen flowmeter calibration device further includes a flow regulating valve group (90) and an adapter joint (100). The gas pipeline of the calibrated module (50) provided with the hydrogen flowmeter to be calibrated is in communication with the gas supply pipeline (10) through the adapter joint (100). The flow regulating valve group (90) is disposed on the gas supply pipeline (10) to control the gas flow rate flowing through the gas supply pipeline (10) and towards the stagnation container (20).

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