Gas flowmeter response time testing device and using method
By using a gas flow meter response time testing device with parallel Venturi nozzles and multi-dimensional parameter acquisition, the problem of unstable flow was solved, and accurate response time testing under different operating conditions was achieved, improving the reference value and data traceability of the test results.
Patent Information
- Application Number
- CN202610015698.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-01-07
- Publication Date
- 2026-03-06
AI Technical Summary
Existing gas flow meter response time testing devices are prone to jetting when adjusting the flow rate by valve opening, resulting in unstable flow and affecting test accuracy.
By employing a first and second Venturi nozzle connected in parallel, combined with a vacuum pump, pressure transmitter, temperature transmitter, and oscilloscope, multi-dimensional parameters are synchronously acquired to eliminate interference errors, record pressure, volume, temperature, and time data, and simulate response performance under different operating conditions.
It enables accurate response time testing under different operating conditions, eliminates the impact of temperature and pressure fluctuations on flow benchmarks, improves the reference value and data traceability of test results, and simplifies the testing process.
Smart Images
Figure CN121612404A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of gas measurement technology, and in particular to a gas flow meter response time testing device and its usage method. Background Technology
[0002] A gas flow meter response time testing device is a specialized instrument used to measure the rapid response capability of a flow meter to changes in gas flow rate. Its core components include a gas source, a flow switching mechanism, a standard flow measurement unit, and a data acquisition system. Existing testing devices typically regulate flow rate by adjusting valve opening, without a flow-limiting sonic nozzle. This can lead to jetting phenomena and unstable flow rates after sudden changes in valve opening. Summary of the Invention
[0003] To address the above issues, a gas flow meter response time testing device and its usage method are proposed.
[0004] The technical solution of the present invention is as follows: a gas flow meter response time testing device, comprising a gas source component, the gas source component being connected to a flow switching mechanism, the other end of the flow switching mechanism being connected to a measuring unit; the flow switching mechanism comprising a first Venturi nozzle and a second Venturi nozzle, the first Venturi nozzle and the second Venturi nozzle being connected in parallel to each other, the inlet ends of the first Venturi nozzle and the second Venturi nozzle being respectively connected to two ports of a three-way valve, the other port of the three-way valve being connected to the gas source component, and the first Venturi nozzle and the second Venturi nozzle being connected in parallel to the measuring unit.
[0005] Preferably, the gas source assembly includes a vacuum pump, the output end of which is connected to a first valve, the other end of which is connected to the inlet end of a vacuum tank, the outlet end of which is connected to a second valve, and the other end of which is connected to a three-way valve.
[0006] Preferably, the vacuum tank is equipped with a pressure transmitter and a temperature transmitter.
[0007] Preferably, a pressure transmitter is provided between the second valve and the three-way valve.
[0008] Preferably, the measurement unit includes a flow meter under test and an oscilloscope, which are connected in parallel. One end of the flow meter under test and the oscilloscope are connected to a flow switching mechanism, and the flow meter under test outputs a signal to the oscilloscope. Preferably, a pressure transmitter and a temperature transmitter are provided between the flow switching mechanism and the measuring unit.
[0009] Preferably, a pressure transmitter is provided on the side away from the flow switching mechanism after the flow meter under test is connected in parallel with the oscilloscope.
[0010] Preferably, the signals from the pressure transmitter, temperature transmitter, first valve, second valve, three-way valve, oscilloscope, first venturi nozzle, and second venturi nozzle are all transmitted to the computer control system.
[0011] A method for using a gas flow meter response time testing device, wherein the steps for testing the response time of a sudden change from 0 flow rate to a set flow rate are as follows: S1. Close the second valve, switch the three-way valve to the branch of the flow corresponding to the first or second Venturi nozzle to be tested, open the first valve, turn on the vacuum pump to evacuate, and observe the value of the pressure transmitter on the vacuum tank. When the pressure is lower than 1 kPa, close the vacuum pump and the first valve. S2. Different back pressure ratios are required to reach the critical state for critical flow Venturi nozzles with different flow rates. Input the critical back pressure ratio of the critical flow Venturi nozzle for testing into the computer control system and set a 10% margin. Before the critical flow Venturi nozzle enters the non-critical state from the critical state, the pressure transmitter sends a signal to the oscilloscope to stop sampling. S3. Open the second valve to send a signal to the oscilloscope, and set the start time at this time; S4. The critical flow Venturi nozzle in the pipeline reaches the critical state instantaneously. The flow rate is the flow rate value at the test point of the flow meter under test. The oscilloscope records the change in the output signal of the flow meter under test. S5. After the system stops working, observe the curve of the output signal of the flow meter under test recorded on the oscilloscope, identify the steady time when the flow meter under test reaches the stabilization device, and the time taken from the start time to the steady time is the response time of the flow meter 31.
[0012] A method for using a gas flow meter response time testing device, wherein the steps are as follows when testing the response time of different flow rate changes: S1. Close the second valve, switch the three-way valve to the branch corresponding to the flow rate of the first Venturi nozzle before the sudden change, open the first valve, turn on the vacuum pump to evacuate air, observe the value of the pressure transmitter on the vacuum tank, and when the pressure is lower than 1 kPa, close the vacuum pump and the first valve. S2. Different back pressure ratios are required to reach the critical state for critical flow Venturi nozzles with different flow rates. Input the critical back pressure ratio of the critical flow Venturi nozzle for testing into the computer control system and set a 10% margin. Before the critical flow Venturi nozzle enters the non-critical state from the critical state, the pressure transmitter sends a signal to the oscilloscope to stop sampling. S3. Open the second valve. The first Venturi nozzle in the pipeline reaches the critical state instantaneously. The flow rate is the flow rate value before the sudden change. Observe the signal curve on the oscilloscope. After the curve is balanced, switch the three-way valve to the second Venturi nozzle and give the oscilloscope a signal. At this time, set the start time. S4. The critical flow Venturi nozzle in the pipeline reaches the critical state instantaneously. The flow rate is the flow rate value at the test point of the flow meter under test. The oscilloscope records the change in the output signal of the flow meter under test. S5. After the system stops working, observe the curve of the output signal of the flow meter under test recorded on the oscilloscope, identify the steady-state time when the flow meter under test reaches the stabilization device, and the time taken from the start time to the steady-state time is the response time of the flow meter under test.
[0013] The beneficial effects of this invention are as follows: This invention simultaneously collects multi-dimensional parameters, eliminating interference errors. pVTt can simultaneously and accurately record four sets of data: pressure, volume, temperature, and time, avoiding the influence of temperature and pressure fluctuations on the flow rate benchmark during individual testing, thus making the response time calculation more accurate.
[0014] It boasts strong operating condition simulation capabilities, covering real-world usage scenarios. It can flexibly adjust operating conditions such as pressure and temperature to simulate the flow meter's response performance under different actual working conditions, making the test results more valuable than those for single operating conditions.
[0015] It offers excellent data traceability and supports in-depth analysis. All parameters are recorded throughout the testing process, allowing for the tracing of the correlation between step changes in flow rate and flow meter output. It can also assist in analyzing the impact of environmental factors on response time.
[0016] High testing efficiency and excellent integration. No need for multiple independent measurement devices; a single pVTt can handle gas source control, parameter acquisition, and data calculation, simplifying the testing process. Attached Figure Description
[0017] Figure 1 This is a schematic diagram of the gas flow meter response time testing device of the present invention.
[0018] The component names corresponding to the various reference numerals in the diagram are as follows: 1. Gas source assembly; 11. Vacuum pump; 12. Vacuum tank; 13. First valve; 14. Second valve; 2. Flow switching mechanism; 21. Three-way valve; 22. First Venturi nozzle; 23. Second Venturi nozzle; 3. Measurement unit; 31. Flow meter under test; 32. Oscilloscope; 4. Pressure transmitter; 5. Temperature transmitter. Detailed Implementation
[0019] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. These embodiments are based on the technical solution of the present invention and provide detailed implementation methods and specific operating procedures. However, the scope of protection of the present invention is not limited to the following embodiments.
[0020] refer to Figure 1As shown in the embodiment of this application, a gas flow meter response time testing device is disclosed, including a gas source component 1. The gas source component 1 is connected to a flow switching mechanism 2 through a pipeline. The other end of the flow switching mechanism 2 is connected to a measurement unit 3 through a pipeline. The flow switching mechanism 2 includes a first Venturi nozzle 22 and a second Venturi nozzle 23. The first Venturi nozzle 22 and the second Venturi nozzle 23 are connected in parallel to each other through a pipeline. The inlet ends of the first Venturi nozzle 22 and the second Venturi nozzle 23 are respectively connected to two ports of a three-way valve 21 through pipelines. The other port of the three-way valve 21 is connected to the gas source component 1 through a pipeline. The first Venturi nozzle 22 and the second Venturi nozzle 23 are connected in parallel and then connected to the measurement unit 3 through a pipeline.
[0021] The gas source assembly 1 includes a vacuum pump 11. The output end of the vacuum pump 11 is connected to a first valve 13 through a pipe. The other end of the first valve 13 is connected to the inlet end of a vacuum tank 12 through a pipe. The outlet end of the vacuum tank 12 is connected to a second valve 14 through a pipe. The other end of the second valve 14 is connected to a three-way valve 21 through a pipe. In this embodiment, both the first valve 13 and the second valve 14 are solenoid valves.
[0022] The vacuum tank 12 is equipped with a pressure transmitter 4 and a temperature transmitter 5; the pressure transmitter 4 is installed on the pipeline between the second valve 14 and the three-way valve 21.
[0023] The measurement unit 3 includes a flow meter under test 31 and an oscilloscope 32. The flow meter under test 31 and the oscilloscope 32 are connected in parallel through a pipe. One end of the flow meter under test 31 and the oscilloscope 32 is connected to the pipe after the first venturi nozzle 22 and the second venturi nozzle 23 are connected in parallel through a pipe. The flow meter under test 31 outputs a signal to the oscilloscope 32.
[0024] A pressure transmitter 4 and a temperature transmitter 5 are installed on the pipeline between the flow switching mechanism 2 and the measuring unit 3; the pressure transmitter 4 is installed on the pipeline on the side away from the flow switching mechanism 2 after the flow meter 31 under test and the oscilloscope 32 are connected in parallel.
[0025] The pressure transmitter 4 and temperature transmitter 5 mentioned above are both prior art and are not within the scope of protection of this application.
[0026] The signals from the pressure transmitter 4, temperature transmitter 5, first valve 13, second valve 14, three-way valve 21, oscilloscope 32, first venturi nozzle 22, and second venturi nozzle 23 are all transmitted to the computer control system. The computer control system is prior art and is not within the scope of protection of this application.
[0027] A method for using a gas flow meter response time testing device, wherein the steps for testing the response time of a sudden change from 0 flow rate to a set flow rate are as follows: S1. Close the second valve 14, switch the three-way valve 21 to the branch of the flow corresponding to the first Venturi nozzle 22 or the second Venturi nozzle 23 to be tested, open the first valve 13, turn on the vacuum pump 11 to pump air, observe the value of the pressure transmitter 4 on the vacuum tank 12, and when the pressure is lower than 1 kPa, close the vacuum pump 11 and the first valve 13. S2. Different back pressure ratios are required to reach the critical state for critical flow Venturi nozzles with different flow rates. Input the critical back pressure ratio of the critical flow Venturi nozzle for testing into the computer control system and set a 10% margin. Before the critical flow Venturi nozzle enters the non-critical state from the critical state, the pressure transmitter sends a signal to the oscilloscope 32 to stop sampling. S3. Open the second valve 14 to send a signal to the oscilloscope 32, and set the start time at this time; S4. The critical flow Venturi nozzle in the pipeline reaches the critical state instantaneously. The flow rate is the flow rate value at the test point of the flow meter under test 31. The oscilloscope 32 records the change in the output signal of the flow meter under test 31. S5. After the device stops working, observe the curve of the output signal of the flow meter under test 31 recorded by the oscilloscope 32, identify the steady time when the flow meter under test 31 reaches the stabilization device, and the time taken from the start time to the steady time is the response time of the flow meter 31.
[0028] A method for using a gas flow meter response time testing device, wherein the steps are as follows when testing the response time of different flow rate changes: S1. Close the second valve 14, switch the three-way valve 21 to the branch of the flow corresponding to the first Venturi nozzle 22 before the sudden change, open the first valve 13, turn on the vacuum pump 11 to pump air, observe the value of the pressure transmitter 4 on the vacuum tank 12, and when the pressure is lower than 1 kPa, close the vacuum pump 11 and the first valve 13. S2. Different back pressure ratios are required to reach the critical state for critical flow Venturi nozzles with different flow rates. Input the critical back pressure ratio of the critical flow Venturi nozzle for testing into the computer control system and set a 10% margin. Before the critical flow Venturi nozzle enters the non-critical state from the critical state, the pressure transmitter sends a signal to the oscilloscope 32 to stop sampling. S3. Open the second valve 14. The first Venturi nozzle 22 in the pipeline instantly reaches the critical state. The flow rate is the flow rate value before the sudden change. Observe the signal curve on the oscilloscope 32. After the curve is balanced, the three-way valve 21 switches to the second Venturi nozzle 23 and sends a signal to the oscilloscope 32. At this time, the start time is set. S4. The critical flow Venturi nozzle in the pipeline reaches the critical state instantaneously. The flow rate is the flow rate value at the test point of the flow meter under test 31. The oscilloscope 32 records the change in the output signal of the flow meter under test 31. S5. After the device stops working, observe the curve of the output signal of the flow meter under test 31 recorded by the oscilloscope 32, identify the steady time when the flow meter under test 31 reaches the stabilization device, and the time taken from the start time to the steady time is the response time of the flow meter under test 31.
[0029] The beneficial effects are: This invention simultaneously collects multi-dimensional parameters, eliminating interference errors. pVTt can accurately record four sets of data simultaneously: pressure, volume, temperature, and time, avoiding the impact of temperature and pressure fluctuations on the flow rate baseline during individual testing, thus making response time calculations more accurate.
[0030] It boasts strong operating condition simulation capabilities, covering real-world usage scenarios. It can flexibly adjust operating conditions such as pressure and temperature to simulate the flow meter's response performance under different actual working conditions, making the test results more valuable than those for single operating conditions.
[0031] It offers excellent data traceability and supports in-depth analysis. All parameters are recorded throughout the testing process, allowing for the tracing of the correlation between step changes in flow rate and flow meter output. It can also assist in analyzing the impact of environmental factors on response time.
[0032] High testing efficiency and excellent integration. No need for multiple independent measurement devices; a single pVTt can handle gas source control, parameter acquisition, and data calculation, simplifying the testing process.
[0033] It should be noted that the terms "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention. The terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. "A plurality of" means two or more. "Installed," "connected," and "joined" should be interpreted broadly; for example, it can refer to a fixed connection, a detachable connection, or an integral connection.
[0034] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any form or substance. It should be noted that those skilled in the art can make various improvements and additions without departing from the present invention, and these improvements and additions should also be considered within the scope of protection of the present invention. Any modifications, alterations, and equivalent changes made by those skilled in the art based on the above-disclosed technical content without departing from the spirit and scope of the present invention are equivalent embodiments of the present invention. Furthermore, any modifications, alterations, and evolutions made to the above embodiments based on the essential technology of the present invention still fall within the scope of the technical solution of the present invention.
Claims
1. A gas flowmeter response time testing apparatus characterized by, The gas source assembly (1) is connected with the flow switching mechanism (2), and the other end of the flow switching mechanism (2) is connected with the measuring unit (3); the flow switching mechanism (2) comprises a first Venturi nozzle (22) and a second Venturi nozzle (23), the first Venturi nozzle (22) and the second Venturi nozzle (23) are connected with each other in parallel, the inlet ends of the first Venturi nozzle (22) and the second Venturi nozzle (23) are respectively connected with two interfaces of the three-way valve (21), the other interface of the three-way valve (21) is connected with the gas source assembly (1), and the first Venturi nozzle (22) and the second Venturi nozzle (23) are connected with the measuring unit (3) in parallel.
2. The gas flow meter response time testing apparatus of claim 1, wherein, The gas source assembly (1) comprises a vacuum pump (11), the output end of the vacuum pump (11) is connected with the first valve (13), the other end of the first valve (13) is connected with the inlet end of the vacuum tank (12), the outlet end of the vacuum tank (12) is connected with the second valve (14), and the other end of the second valve (14) is connected with the three-way valve (21).
3. The gas flow meter response time testing apparatus of claim 2, wherein, The vacuum tank (12) is provided with a pressure transmitter (4) and a temperature transmitter (5).
4. The gas flow meter response time testing apparatus of claim 2, wherein, The pressure transmitter (4) is arranged between the second valve (14) and the three-way valve (21).
5. The gas flow meter response time testing apparatus of claim 2, wherein, The measuring unit (3) comprises a detected flowmeter (31) and an oscilloscope (32), the detected flowmeter (31) and the oscilloscope (32) are connected with each other in parallel, one end of the detected flowmeter (31) and the oscilloscope (32) is connected with the flow switching mechanism (2), and the detected flowmeter (31) outputs a signal to the oscilloscope (32).
6. The gas flow meter response time testing apparatus of claim 1, wherein, The pressure transmitter (4) and the temperature transmitter (5) are arranged between the flow switching mechanism (2) and the measuring unit (3).
7. The gas flow meter response time testing apparatus of claim 5, wherein, The pressure transmitter (4) is arranged on the side, away from the flow switching mechanism (2), of the parallel connection of the detected flowmeter (31) and the oscilloscope (32).
8. The gas flow meter response time testing apparatus of claim 6, wherein, The signals of the pressure transmitter (4), the temperature transmitter (5), the first valve (13), the second valve (14), the three-way valve (21), the oscilloscope (32), the first Venturi nozzle (22) and the second Venturi nozzle (23) are transmitted to a computer control system.
9. A method of using the gas flow meter response time testing apparatus of any one of claims 1-7, wherein, When the response time test from 0 flow to a set flow is performed, the following steps are taken: S1, the second valve (14) is closed, the three-way valve (21) is switched to the branch corresponding to the flow of the first Venturi nozzle (22) or the second Venturi nozzle (23) to be tested, the first valve (13) is opened, the vacuum pump (11) is started to pump air, and the value of the pressure transmitter (4) on the vacuum tank (12) is observed; when the pressure is lower than 1kPa, the vacuum pump (11) and the first valve (13) are closed; S2, the critical flow Venturi nozzle corresponding to different flows has different back pressure ratios when reaching a critical state, the critical back pressure ratio of the critical flow Venturi nozzle for testing is input in the computer control system, a 10% margin is set, the pressure transmitter sends a signal to the oscilloscope (32) before the critical flow Venturi nozzle enters a non-critical state from the critical state, and sampling is stopped; S3, the second valve (14) is opened, a signal is sent to the oscilloscope (32), and the starting time is set at this moment. S4, the critical flow Venturi nozzle in the pipeline instantaneously reaches the critical state, the flow rate is the flow rate value at the test point of the flowmeter (31) under test, and the oscilloscope (32) records the change in the output signal of the flowmeter (31) under test; S5, after the system stops working, the curve of the output signal of the flowmeter (31) under test recorded by the oscilloscope (32) is observed, the stable time when the flowmeter (31) under test reaches the stabilizing device is identified, and the time from the start time to the stable time is the response time of the flowmeter (31) under test.
10. A method of using the gas flow meter response time testing apparatus of any one of claims 1-7, wherein, When the response time to different flow rate mutations is tested, the steps are as follows: S1, close the second valve (14), switch the three-way valve (21) to the branch corresponding to the flow rate of the first Venturi nozzle (22) before the mutation, open the first valve (13), and start the vacuum pump (11) to pump air. When the pressure value of the pressure transmitter (4) on the vacuum tank (12) is lower than 1 kPa, close the vacuum pump (11) and the first valve (13); S2, the critical flow Venturi nozzle corresponding to different flow rates has different back pressure ratios when reaching the critical state. The critical back pressure ratio of the critical flow Venturi nozzle for testing is input in the computer control system, a 10% margin is set, the pressure transmitter sends a signal to the oscilloscope (32) before the critical flow Venturi nozzle enters the non-critical state from the critical state, and the sampling is stopped; S3, open the second valve (14), the first Venturi nozzle (22) in the pipeline instantaneously reaches the critical state, the flow rate is the flow rate value before the mutation, the signal curve on the oscilloscope (32) is observed, and after the curve is balanced, the three-way valve (21) is switched to the second Venturi nozzle (23) to give a signal to the oscilloscope (32), at this time, the start time is set; S4, the critical flow Venturi nozzle in the pipeline instantaneously reaches the critical state, the flow rate is the flow rate value at the test point of the flowmeter (31) under test, and the oscilloscope (32) records the change in the output signal of the flowmeter (31) under test; S5, after the system stops working, the curve of the output signal of the flowmeter (31) under test recorded by the oscilloscope (32) is observed, the stable time when the flowmeter (31) under test reaches the stabilizing device is identified, and the time from the start time to the stable time is the response time of the flowmeter (31) under test.