Efficient flowmeter detection and calibration method based on gravitational potential energy

Abstract

The invention relates to the technical field of detection and calibration, and particularly discloses an efficient flowmeter detection and calibration method based on gravitational potential energy, which comprises the following steps: S1, building a detection and calibration device which comprises a height-adjustable water tank, a capacitance liquid level sensing unit, a water inlet control unit, a flow regulation and calibration unit and a control and display unit; s2, liquid level signals in the height-adjustable water tank are collected in real time through a capacitance liquid level sensing unit and fed back to a control and display unit, the control and display unit regulates and controls an execution element of a water inlet control unit, and the liquid level difference in the water tank is stably controlled within a preset threshold value; and S3, the installation height of the height-adjustable water tank is adjusted to change the gravitational potential energy of the fluid. The method effectively solves the problems of poor range adaptability, insufficient precision, low efficiency and the like in the existing flowmeter calibration technology, has universality, stability, high precision and high efficiency, and is suitable for flowmeter batch calibration scenes in the fields of industrial production, energy metering and the like.

Description

Technical Field

[0001] This invention relates to the field of testing and calibration technology, specifically to an efficient testing and calibration method for flow meters based on gravitational potential energy. Background Technology

[0002] As the core equipment for fluid flow measurement, flow meters are widely used in various fields such as industrial production, energy metering, water treatment, and transportation. Their measurement accuracy directly affects production efficiency control, cost accounting, and trade fairness. Therefore, regular testing and calibration of flow meters is a crucial step in ensuring their measurement reliability. However, existing flow meter testing and calibration technologies still have many shortcomings and are insufficient to meet the needs of practical applications.

[0003] 1. Poor range adaptability: Traditional calibration devices mostly rely on fixed power sources (such as constant flow pumps), and the maximum flow rate of the pipeline cannot be flexibly adjusted. When facing flow meters to be tested with different ranges, it is necessary to replace the calibration equipment with different specifications, which not only increases the cost of equipment purchase and maintenance, but also prolongs the test preparation time and makes the operation complex.

[0004] 2. Insufficient liquid level stability: During calibration, fluctuations in the liquid level within the tank directly affect the stability of the fluid's gravitational potential energy, leading to deviations in the actual flow rate. Existing technologies often employ simple liquid level control methods, lacking precise closed-loop regulation mechanisms. This results in significant liquid level fluctuations, failing to guarantee consistent flow output and impacting the reliability of the calibration benchmark.

[0005] 3. Limited detection accuracy: Existing flow calculations mostly use indirect measurement methods such as differential pressure method and flow velocity method, which are easily affected by environmental factors such as fluid viscosity and pipeline resistance. At the same time, core measurement components such as weighing sensors and timing modules lack standardized calibration procedures. Random errors and systematic errors are superimposed, resulting in insufficient accuracy of actual flow calculation, which is difficult to meet the needs of high-precision metering scenarios.

[0006] 4. Low efficiency of batch testing: In traditional calibration methods, the switching of the flow meter under test requires manual operation. The switching process is time-consuming and easily causes fluid disturbance. It takes a long time to restore the flow stability, which cannot achieve continuous batch testing. It is only suitable for small batch samples and is difficult to match the efficiency requirements of large-scale industrial calibration.

[0007] 5. Inadequate error control: Existing technologies lack systematic control schemes for factors affecting calibration accuracy, such as liquid level fluctuations, switching disturbances, and sensor deviations. They have not formed a full-process error suppression mechanism, resulting in relatively large errors in calibration results, which cannot meet the stringent metrological accuracy requirements of scenarios such as precision industry and energy trade.

[0008] In view of the shortcomings of the existing technology, there is an urgent need for a flow meter testing and calibration method with a wide range of measurement range, high calibration accuracy, high detection efficiency and stable operation, so as to solve the many problems existing in the current technology. Summary of the Invention

[0009] To address the shortcomings of existing technologies, this invention provides a high-efficiency detection and calibration method for flow meters based on gravitational potential energy, thus solving the problems mentioned in the background technology.

[0010] To achieve the above objectives, the present invention provides the following technical solution: a high-efficiency detection and calibration method for flow meters based on gravitational potential energy, comprising the following steps:

[0011] S1. Set up a testing and calibration device, including an adjustable height water tank, a capacitive liquid level sensing unit, a water inlet control unit, a flow regulation and calibration unit, and a control and display unit;

[0012] S2. The liquid level signal in the adjustable height water tank is collected in real time by the capacitive liquid level sensing unit and fed back to the control and display unit, which regulates the actuator of the water inlet control unit to stably control the liquid level difference in the water tank within the preset threshold.

[0013] S3. Adjust the installation height of the adjustable height water tank to change the gravitational potential energy of the fluid, thereby adjusting the maximum flow rate of the pipeline to adapt to the calibration requirements of flow meters under test with different ranges.

[0014] S4. Collect fluid through the measuring cup of the flow regulation and calibration unit, obtain fluid mass parameters using a weighing sensor, calculate the actual flow rate by combining timing data, and adjust it to the target flow rate.

[0015] S5. Switch the flow meter under test to the detection loop. By comparing the target flow rate with the measurement value of the flow meter under test through the control and display unit, the single flow meter detection and calibration is completed. Repeat this step to achieve batch testing.

[0016] Preferably, the capacitive liquid level sensing unit includes capacitive liquid level sensor I and capacitive liquid level sensor II arranged at intervals along the vertical direction, with a distance between them. The preset threshold mentioned in S2 is ;

[0017] Real-time liquid level difference in water tank Calculated using formula (1):

[0018] ;

[0019] in, The liquid level height sensed by capacitive level sensor I, in units of... ; The liquid level height sensed by capacitive level sensor II, in units of... And it must meet the following requirements: ;

[0020] Signal sampling frequency of capacitive liquid level sensor I and capacitive liquid level sensor II This ensures that changes in liquid level are captured in real time.

[0021] Preferably, the liquid level control in S2 adopts closed-loop regulation logic, specifically as follows:

[0022] when hour, The initial water replenishment threshold is set to the installation height of capacitive level sensor I, in units of... The servo ball valve I of the water inlet control unit is fully open for water replenishment;

[0023] when When the capacitive liquid level sensor II is installed at the specified height, the logic controller of the control and display unit initiates proportional adjustment to adjust the opening of the servo ball valve I.

[0024] when hour, This represents the real-time liquid level in the water tank, in units of... The logic controller performs PID fine-tuning to adjust the liquid level difference. The conditions of formula (1) are met, and the amplitude of liquid level fluctuation is... Calculate using formula (2):

[0025] ;

[0026] in, for The maximum real-time internal liquid level, in units of ; for Minimum real-time internal liquid level, in units of ;Require .

[0027] Preferably, the actual traffic in S4 Calculated using formula (4):

[0028] ;

[0029] in, Actual flow rate, unit: ; The mass of fluid in the measuring cup measured by the weighing sensor, in units of... Measurement accuracy ; The density of a fluid is the density of water at room temperature. ; The time taken for traffic collection, in units of Timing accuracy .

[0030] Preferably, in S4, the opening of the servo ball valve II of the flow regulation and calibration unit is adjusted. To achieve the target flow rate regulation, the relationship between the opening degree of servo ball valve II and the flow rate satisfies formula (5):

[0031] ;

[0032] in, This is an opening-flow function, without units. The opening degree of servo ball valve II, with a value range of... Adjustment precision ; Obtained by linear fitting method , This is the flow gain coefficient, in units of... ; The zero-biased flow coefficient, in units of ; and All were calibrated using multiple sets of opening-flow experimental data.

[0033] Preferably, the test calibration result of the flow meter under test in S5 is obtained through relative error. The relative error is determined by formula (6):

[0034] ;

[0035] in, The relative error of the flow meter under test is expressed in units of _____. ; The target flow rate determined for S4, in units of ; The real-time measurement value of the flow meter under test, in units of ;

[0036] Preset tolerance ,when When the flow meter under test is deemed qualified, it is considered qualified. If the error value is not found, the flow meter under test is deemed unqualified and the error value is recorded.

[0037] Preferably, the adjustable height water tank is equipped with a stable liquid level baffle, which is vertically arranged on one side of the water inlet inside the water tank.

[0038] Preferably, the timing in S4 And in Continuous collection within a time period Value, sampling interval Take the average , For the first The mass measurement value in seconds is substituted into formula (4) to calculate the actual flow rate. Reduce the impact of random errors;

[0039] In step (5), the water circuit is switched using an electrically controlled directional valve, and the switching time is... After switching, a stable period of time is required. Samples were collected after the fluid flow stabilized. This avoids measurement deviations caused by switching disturbances.

[0040] Preferably, the test calibration result of the flow meter under test in S5 is determined by the relative error δ, and the relative error is calculated by formula (6):

[0041] ;

[0042] in, The relative error of the flow meter under test is expressed in % (%). The target flow rate is defined in S4, in m³ / h. This is the real-time measurement value of the flow meter under test, in m³ / h.

[0043] Preset tolerance The judgment rule is as follows:

[0044] when When the flow meter under test is deemed qualified, it is then determined that the flow meter is qualified.

[0045] when If the error occurs, it is deemed unqualified and the error value is recorded.

[0046] Preferably, the adjustable height water tank is equipped with a vertically arranged stabilizing liquid level baffle, the installation requirements of which are as follows:

[0047] high , : Distance from the top of the baffle to the bottom of the water tank, unit: mm; horizontal distance Distance from the water inlet;

[0048] The performance of the baffle is verified by formula (7):

[0049] ;

[0050] Require: ; The peak / trough value of the liquid level within 10 seconds after the baffle buffer is applied, in mm.

[0051] Baffle calibration steps:

[0052] Measure the initial distance ;

[0053] Fully open servo ball valve I for water replenishment, record fluctuations on both sides of the baffle. Inlet side Water outlet side;

[0054] like ,according to Increase the adjustment step by 10mm until... .

[0055] This invention provides a highly efficient detection and calibration method for flow meters based on gravitational potential energy, which has the following beneficial effects:

[0056] 1. Wide range adaptability and strong versatility: By adjusting the installation height of the adjustable height water tank, the gravitational potential energy of the fluid can be flexibly changed, thereby adjusting the maximum flow rate of the pipeline. The calibration requirements of flow meters under test with different ranges can be met without replacing the core equipment, which greatly reduces the equipment investment and maintenance costs, improves the adaptability of the method to different testing scenarios, and is suitable for the calibration of flow meters of various specifications.

[0057] 2. High liquid level stability and consistent flow output: The dual-capacitor liquid level sensor collects the liquid level signal in the water tank in real time. Combined with the closed-loop control logic of "full opening water replenishment - proportional adjustment - PID fine adjustment", the liquid level difference can be stably controlled within the preset range, effectively suppressing liquid level fluctuations. At the same time, the stable liquid level baffle in the water tank further buffers the impact of the incoming water flow, reduces the impact of liquid level fluctuations on the flow rate, ensures the stability of the fluid's gravitational potential energy, and guarantees the consistency and stability of the flow output.

[0058] 3. High calibration accuracy and reliable results: The system directly measures fluid mass and acquisition time using a weighing sensor and timing module, and obtains the actual flow rate through direct calculation, reducing systematic errors caused by indirect measurement methods. Simultaneously, standardized calibration procedures are established for core components such as the capacitive level sensor, weighing sensor, and timing module to ensure the accuracy of the measurement benchmark. Furthermore, measures such as continuous data acquisition and averaging, and waiting for flow rate stabilization after switching, reduce the impact of random errors and switching disturbances, significantly improving calibration accuracy and meeting the needs of high-precision metrology scenarios.

[0059] 4. High testing efficiency and support for batch calibration: The flow meter under test can be quickly switched through the electronically controlled reversing valve. The switching process does not require manual intervention. After switching, only a short waiting time is required to restore flow stability. Multiple flow meters can be calibrated continuously, realizing batch testing, significantly shortening the calibration cycle of a single flow meter, and improving the efficiency of large-scale industrial calibration.

[0060] 5. High degree of automation and convenient operation: The entire calibration process is automatically completed by the control and display unit, including liquid level regulation, flow calculation, target flow adjustment, error comparison and result judgment, without the need for complicated manual operation; at the same time, by fitting the valve opening-flow correlation, the target flow can be quickly and accurately set by adjusting the valve opening, simplifying the operation process and reducing the reliance on the professional skills of the operators.

[0061] 6. High reliability and traceable results: A re-inspection process is set up for unqualified flow meters under test. By re-clamping, repeating calibration, and averaging multiple data collections, the random errors of a single measurement are avoided, ensuring the reliability of the calibration results. At the same time, key data such as target flow rate, flow meter measurement value, and relative error are automatically recorded, and an error analysis report can be generated to provide a complete traceability basis for the calibration results.

[0062] In summary, this invention effectively solves the problems of poor range adaptability, insufficient accuracy, and low efficiency in existing flowmeter calibration technologies. It combines versatility, stability, high accuracy, and high efficiency, making it suitable for batch calibration scenarios of flowmeters in fields such as industrial production and energy metering. It has significant practical value and promising prospects for promotion. Attached Figure Description

[0063] Figure 1 This is a schematic diagram of the process of a high-efficiency detection and calibration method for flow meters based on gravitational potential energy, as described in this invention.

[0064] Figure 2 This is a block diagram illustrating the principle of an efficient flowmeter detection and calibration method based on gravitational potential energy, as described in this invention. Detailed Implementation

[0065] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0066] like Figures 1-2 As shown, the present invention provides a technical solution: a high-efficiency detection and calibration method for flow meters based on gravitational potential energy, comprising the following steps:

[0067] S1. Set up a testing and calibration device, including an adjustable height water tank, a capacitive liquid level sensing unit, a water inlet control unit, a flow regulation and calibration unit, and a control and display unit;

[0068] S2. The liquid level signal in the adjustable height water tank is collected in real time by the capacitive liquid level sensing unit and fed back to the control and display unit, which regulates the actuator of the water inlet control unit to stably control the liquid level difference in the water tank within the preset threshold.

[0069] S3. Adjust the installation height of the adjustable height water tank to change the gravitational potential energy of the fluid, thereby adjusting the maximum flow rate of the pipeline to adapt to the calibration requirements of flow meters under test with different ranges.

[0070] S4. Collect fluid through the measuring cup of the flow regulation and calibration unit, obtain fluid mass parameters using a weighing sensor, calculate the actual flow rate by combining timing data, and adjust it to the target flow rate.

[0071] S5. Switch the flow meter under test to the detection loop. By comparing the target flow rate with the measurement value of the flow meter under test through the control and display unit, the single flow meter detection and calibration is completed. Repeat this step to achieve batch testing.

[0072] More specifically, the capacitive liquid level sensing unit includes capacitive liquid level sensor I and capacitive liquid level sensor II arranged at intervals along the vertical direction, with a distance between them. The preset threshold mentioned in S2 is ;

[0073] Real-time liquid level difference in water tank Calculated using formula (1):

[0074] ;

[0075] in, The liquid level height sensed by capacitive level sensor I, in units of... ; The liquid level height sensed by capacitive level sensor II, in units of... And it must meet the following requirements: ;

[0076] Signal sampling frequency of capacitive liquid level sensor I and capacitive liquid level sensor II This ensures that changes in liquid level are captured in real time.

[0077] The specific steps for periodic calibration of capacitive liquid level sensors are as follows:

[0078] S11, Adjust the precision level Standard level gauge and , Install them coaxially along the vertical direction of the water tank to ensure that the measurement axes of the three parts coincide;

[0079] S12. Fill the adjustable height water tank with water in stages, maintaining a stable liquid level after each stage. Simultaneously record the standard level gauge reading. and , Induction reading , A total of Group data ( Value Coverage to (range of measurement).

[0080] S13. Calculate the sensor deviation for each set of data. , ,like or The sensitivity coefficient of the sensor is corrected by controlling and displaying the touch screen of the unit.

[0081] S14. Repeat steps S12-S13. Next, until All groups in the sub-calibration and Complete sensor calibration.

[0082] In one specific embodiment of the present invention, the capacitive liquid level sensing unit adopts a dual-sensor collaborative monitoring scheme: capacitive liquid level sensor I and capacitive liquid level sensor II are arranged at a distance of 15mm along the vertical direction of the water tank, and the preset threshold for liquid level difference in step S2 is set to 15mm, using the formula... The system calculates real-time fluctuations in the water tank level (where h1 and h2 are the water level heights sensed by the two sensors), ensuring the level difference is always controlled within ≤15mm. Simultaneously, the sensor signal sampling frequency is ≥10Hz, enabling rapid capture of dynamic changes in the water level and avoiding flow calculation errors caused by response delays. To further improve detection accuracy, this invention also includes a standardized sensor calibration procedure: a standard level gauge with an accuracy class ≥0.05mm is coaxially installed with the two sensors. Water is added in stages and stabilized for 30 seconds, followed by simultaneous acquisition of 10 sets of readings covering the entire range. The sensor deviation is then calculated. , ( (Using the standard level gauge reading), if the deviation exceeds 0.2mm, the sensor sensitivity coefficient is corrected, and calibration is repeated until all data deviations in three tests are ≤0.2mm. This design effectively eliminates the impact of level fluctuations and sensor errors on flow calculation through precise temperature control with dual-sensor spacing matching thresholds, real-time response from high-frequency sampling, and a rigorous calibration process. This provides a core guarantee for the stability of flow output based on gravitational potential energy, ultimately significantly improving the accuracy and reliability of flow meter calibration results.

[0083] More specifically, the liquid level control in S2 adopts closed-loop regulation logic, as follows:

[0084] when hour, The initial water replenishment threshold is set to the installation height of capacitive level sensor I, in units of... The servo ball valve I of the water inlet control unit is fully open for water replenishment;

[0085] when When the capacitive liquid level sensor II is installed at the specified height, the logic controller of the control and display unit initiates proportional adjustment to adjust the opening of the servo ball valve I.

[0086] when hour, This represents the real-time liquid level in the water tank, in units of... The logic controller performs PID fine-tuning to adjust the liquid level difference. The conditions of formula (1) are met, and the amplitude of liquid level fluctuation is... Calculate using formula (2):

[0087] ;

[0088] in, for The maximum real-time internal liquid level, in units of ; for Minimum real-time internal liquid level, in units of ;Require ;

[0089] The parameter tuning steps for PID fine-tuning are as follows:

[0090] S21. Initial setting of PID parameters: proportional coefficient Integral coefficient Differential coefficients ;

[0091] S22, Record PID adjustment within Fluctuation curve, calculate fluctuation amplitude ;

[0092] S23, if ,according to" Increase , Increase , Increase The parameters are iteratively adjusted using the step size, and S2 is repeated until... Determine the final PID parameters.

[0093] Pipeline flow coefficient The calibration steps are as follows:

[0094] S31. Measure key pipeline parameters: Pipeline inner diameter (Unit is) Measurement accuracy Pipeline inner wall roughness (Unit is) (Measured by a surface roughness tester).

[0095] S32, Fixed Switch the electronically controlled directional valve to the measuring cup water circuit and collect the water sample. Internal fluid mass According to the formula Calculate the actual maximum flow rate ( , );

[0096] S33, will , Substitute into formula (3) and calculate backwards. ;

[0097] S34, Change to , Repeat S2-S3 to obtain , , Take the average This serves as the calibration value for the pipeline flow coefficient.

[0098] Step S2 employs a phased closed-loop control logic to achieve precise liquid level control: when the liquid level h2 in the tank is lower than the initial water replenishment threshold h0 (i.e., the installation height of capacitive level sensor I), servo ball valve I fully opens to quickly replenish water, ensuring efficient liquid level recovery; when When the capacitive level sensor II reaches its installation height, the logic controller initiates proportional adjustment to smoothly transition the valve opening, preventing a sudden rise in liquid level; when the real-time liquid level... When positioned between two sensors, the liquid level is precisely controlled through PID fine-tuning, combined with... The method for calculating the fluctuation amplitude strictly controls the liquid level fluctuation within 10 seconds. Within this range, the PID parameter tuning process of "initial parameter setting - fluctuation curve recording - step size iterative adjustment" can be used to specifically optimize the proportional, integral, and derivative coefficients, ensuring the response speed and stability of liquid level regulation; at the same time, the pipeline flow coefficient... The calibration process involves precisely measuring key parameters such as the pipe's inner diameter and inner wall roughness. Fluid mass is collected at three different water tank heights (2.0m, 1.0m, and 3.0m) to calculate the actual flow rate, and then the corresponding flow rates at different heights are calculated. The average value is taken as the calibration result. This design achieves fine control of liquid level through staged closed-loop regulation and PID parameter optimization, suppressing flow fluctuations from the source. It also eliminates the influence of pipeline parameter differences on flow calculation through multi-condition calibration, providing a reliable basis for accurate flow calculation. The synergistic effect of the two significantly improves the accuracy and consistency of flow meter calibration, effectively solving the problems of insufficient liquid level stability and large flow calculation deviation in the existing technology.

[0099] More specifically, the actual traffic in S4 Calculated using formula (4):

[0100] ;

[0101] in, Actual flow rate, unit: ; The mass of fluid in the measuring cup measured by the weighing sensor, in units of... Measurement accuracy ; The density of a fluid is the density of water at room temperature. ; The time taken for traffic collection, in units of Timing accuracy ;

[0102] The calibration steps for the load cell are as follows:

[0103] S41, Select One standard weight (with a mass of respectively) , , Precision level class);

[0104] S42. Place the standard weights sequentially on the measuring cup support platform of the weighing sensor, and record the displayed mass of the sensor. With standard mass of weights ;

[0105] S43. Calculate calibration deviation ,like The sensor's measurement coefficient is corrected by the logic controller, and S2 is repeated until all weights are... , complete calibration.

[0106] More specifically, in S4, the opening of the servo ball valve II of the flow regulation and calibration unit is adjusted. To achieve the target flow rate regulation, the relationship between the opening degree of servo ball valve II and the flow rate satisfies formula (5):

[0107] ;

[0108] in, This is an opening-flow function, without units. The opening degree of servo ball valve II, with a value range of... Adjustment precision ; Obtained by linear fitting method , This is the flow gain coefficient, in units of... ; The zero-biased flow coefficient, in units of ; and All were calibrated using multiple sets of opening-flow experimental data;

[0109] Opening-flow function The calibration steps are as follows:

[0110] S51, Settings The calibration interval is Select , , … common One calibration opening;

[0111] S52. For each calibrated opening degree, collect data after maintaining a stable liquid level. Internal fluid mass Calculate the corresponding flow rate according to formula (4). ;

[0112] S53, will , Substituting into formula (5), we get ,form Group data;

[0113] S54. Using the least squares method to... Linear fitting was performed on the set of data to obtain... ,in , ( For the first A standard opening, For the first Each opening corresponds to , , for The mean, for (mean).

[0114] More specifically, the test calibration results of the flow meter under test in S5 are obtained through relative error. The relative error is determined by formula (6):

[0115] ;

[0116] in, The relative error of the flow meter under test is expressed in units of _____. ; The target flow rate determined for S4, in units of ; The real-time measurement value of the flow meter under test, in units of ;

[0117] Preset tolerance ,when When the flow meter under test is deemed qualified, it is considered qualified. If the error value is not found, the flow meter under test is deemed unqualified and the error value is recorded.

[0118] The re-inspection steps for unqualified flow meters are as follows:

[0119] S61. For flow meters that fail the test, re-clamp them into the test circuit and check the sealing of the pipeline connection.

[0120] S62. Repeat S2-S4 to reconfirm. ,collection Second-rate ,calculate Second-rate mean ;

[0121] S36, if The original judgment result was revised to qualified; if Confirm that the flow meter under test is unqualified and generate an error analysis report (including...). , , of (Secondary data).

[0122] More specifically, the adjustable height water tank is equipped with a stable liquid level baffle, which is vertically arranged on one side of the water inlet inside the water tank;

[0123] The installation and calibration steps for the stabilized liquid level baffle are as follows:

[0124] S71. Measure the horizontal distance between the baffle and the inlet. ,Require Ensure that the incoming water flow is adequately buffered by the baffle;

[0125] S72. Open servo ball valve I to its maximum opening for water replenishment, and record the liquid level fluctuations before and after the baffle during the water replenishment process. (Water inlet side of the baffle) (Water outlet side of the baffle);

[0126] S73, if ,according to" Increase Adjust the position of the baffle by step size, repeat S2, until... Determine the final installation position of the baffle.

[0127] More specifically, the timing in S4 And in Continuous collection within a time period Value, sampling interval Take the average , For the first The mass measurement value in seconds is substituted into formula (4) to calculate the actual flow rate. Reduce the impact of random errors;

[0128] In step (5), the water circuit is switched using an electrically controlled directional valve, and the switching time is... After switching, a stable period of time is required. Samples were collected after the fluid flow stabilized. To avoid measurement deviations caused by switching disturbances;

[0129] It also includes the calibration steps for the timing module, specifically:

[0130] S1, Using precision The standard timer starts synchronously with the timing module of the detection device;

[0131] S2, Set the timer duration , , Record the timing readings of the detection device respectively. Readings from a standard timer ;

[0132] S3, Calculate timing deviation ,like The clock frequency of the timing module is corrected by the logic controller, and S2 is repeated until all timing durations are completed. , complete calibration.

[0133] More specifically, the test calibration result of the flow meter under test in S5 is determined by the relative error δ, which is calculated by formula (6):

[0134] ;

[0135] in, The relative error of the flow meter under test is expressed in % (%). The target flow rate is defined in S4, in m³ / h. This is the real-time measurement value of the flow meter under test, in m³ / h.

[0136] Preset tolerance The judgment rule is as follows:

[0137] when When the flow meter under test is deemed qualified, it is then determined that the flow meter is qualified.

[0138] when If the error occurs, it is deemed unqualified and the error value is recorded.

[0139] It also includes a re-inspection process for defective flow meters:

[0140] Re-inspection preparation: Re-clamp the defective flow meter and check the pipeline sealing;

[0141] Data retesting: Repeat S2-S4 to determine Collected 3 times ;

[0142] Result correction:

[0143] If 3 times mean Revised to qualified;

[0144] like Generate an error analysis report (including) , and 3 times data).

[0145] By clearly defining the relative error δ between the target flow rate and the measured value of the flow meter under test as the core judgment index, and combining it with the quantitative formula (6), the calibration results are accurately quantitatively evaluated, with a preset allowable error of [0.1%, 1.0%]. Adapting to calibration scenarios with varying accuracy requirements, this design ensures consistent and practical application-appropriate judgment standards. It also includes a re-inspection process for defective flowmeters. By re-clamping and checking for leaks, interference from installation and piping issues is eliminated. Steps S2-S4 are repeated to obtain a stable target flow rate, and three measurement values ​​are collected and averaged. This effectively avoids random errors from single measurements and corrects misjudgments caused by temporary disturbances. Finally, an error analysis report containing key data ensures traceability of results. The overall design significantly improves the rigor, accuracy, and reliability of calibration judgments, solving the problems of vague error judgment standards and lack of effective re-inspection mechanisms in existing technologies, which lead to low reliability of results.

[0146] More specifically, the adjustable height water tank is equipped with a vertically arranged stabilizing liquid level baffle, the installation requirements of which are as follows:

[0147] high , : Distance from the top of the baffle to the bottom of the water tank, unit: mm; horizontal distance Distance from the water inlet;

[0148] The performance of the baffle is verified by formula (7):

[0149] ;

[0150] Require: ; The peak / trough value of the liquid level within 10 seconds after the baffle buffer is applied, in mm.

[0151] Baffle calibration steps:

[0152] Measure the initial distance ;

[0153] Fully open servo ball valve I for water replenishment, record fluctuations on both sides of the baffle. Inlet side Water outlet side;

[0154] like ,according to Increase the adjustment step by 10mm until... .

[0155] Flow measurement optimization:

[0156] Timing time ;

[0157] Seconds of data collection quality Take the average Substitute into formula (4) to calculate ;

[0158] Waterway switching control:

[0159] Switching time of electronically controlled directional valve ;

[0160] Stabilization time after switching Re-collection .

[0161] Timing module calibration steps:

[0162] Using a standard timer (accuracy) Synchronized timing;

[0163] Test durations of 60s, 120s, and 180s, and record device readings. Compared with standard value ;

[0164] If there is a deviation Adjust the clock frequency until all tests are completed. .

[0165] By clearly defining the quantitative installation requirements and performance verification standards for the stable liquid level baffle, and in conjunction with the calibration process of "measurement-water replenishment test-step adjustment," the impact of the incoming water flow can be effectively buffered, and the liquid level fluctuation on the outlet side of the baffle can be precisely controlled within the allowable range within 10 seconds, providing a core guarantee for the stability of the fluid's gravitational potential energy. Combined with parameter optimization in the flow measurement stage (continuous sampling and averaging for t≥60s) and high-precision calibration of the timing module (correcting deviations to ≥0.001s using a standard timer), the system effectively ensures stable fluid gravitational potential energy. This reduces random errors at the measurement benchmark and data acquisition level, and further reduces them through rapid switching of the electronically controlled directional valve. ≤0.5s) and steady wait ( (≥5s) Avoids disturbances during water path switching, forming a full-process error control system of "stabilizing liquid level at the source - ensuring accuracy with the benchmark - reducing errors in data acquisition". In conjunction with the aforementioned relative error judgment and re-inspection mechanism, it further solves the problem of insufficient calibration accuracy caused by liquid level fluctuation, benchmark deviation and disturbance interference in the existing technology, significantly improving the repeatability and reliability of flowmeter calibration results, and providing reliable technical support for high-precision metering scenarios.

[0166] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A high-efficiency detection and calibration method for flow meters based on gravitational potential energy, characterized in that, Includes the following steps: S1. Set up a testing and calibration device, including an adjustable height water tank, a capacitive liquid level sensing unit, a water inlet control unit, a flow regulation and calibration unit, and a control and display unit; S2. The liquid level signal in the adjustable height water tank is collected in real time by the capacitive liquid level sensing unit and fed back to the control and display unit, which regulates the actuator of the water inlet control unit to stably control the liquid level difference in the water tank within the preset threshold. S3. Adjust the installation height of the adjustable height water tank to change the gravitational potential energy of the fluid, thereby adjusting the maximum flow rate of the pipeline to adapt to the calibration requirements of flow meters under test with different ranges. S4. Collect fluid through the measuring cup of the flow regulation and calibration unit, obtain fluid mass parameters using a weighing sensor, calculate the actual flow rate by combining timing data, and adjust it to the target flow rate. S5. Switch the flow meter under test to the detection loop. By comparing the target flow rate with the measurement value of the flow meter under test through the control and display unit, the single flow meter detection and calibration is completed. Repeat this step to achieve batch testing.

2. The efficient detection and calibration method for a flowmeter based on gravitational potential energy according to claim 1, characterized in that, The capacitive liquid level sensing unit includes capacitive liquid level sensor I and capacitive liquid level sensor II arranged at intervals along the vertical direction, with a distance between them. The preset threshold mentioned in S2 is ; Real-time liquid level difference in water tank Calculated using formula (1): ； in, The liquid level height sensed by capacitive level sensor I, in units of... ; The liquid level height sensed by capacitive level sensor II, in units of... And it must meet the following requirements: ; Signal sampling frequency of capacitive liquid level sensor I and capacitive liquid level sensor II This ensures that changes in liquid level are captured in real time.

3. The efficient detection and calibration method for a flowmeter based on gravitational potential energy according to claim 2, characterized in that, The liquid level control in S2 adopts closed-loop regulation logic, specifically: when hour, The initial water replenishment threshold is set to the installation height of capacitive level sensor I, in units of... The servo ball valve I of the water inlet control unit is fully open for water replenishment; when When the capacitive liquid level sensor II is installed at the specified height, the logic controller of the control and display unit initiates proportional adjustment to adjust the opening of the servo ball valve I. when hour, This represents the real-time liquid level in the water tank, in units of... The logic controller performs PID fine-tuning to adjust the liquid level difference. The conditions of formula (1) are met, and the amplitude of liquid level fluctuation is... Calculate using formula (2): ； in, for The maximum real-time internal liquid level, in units of ; for Minimum real-time internal liquid level, in units of ;Require .

4. The efficient detection and calibration method for a flowmeter based on gravitational potential energy according to claim 3, characterized in that, Actual flow in S4 Calculated using formula (4): ； in, Actual flow rate, unit: ; The mass of fluid in the measuring cup measured by the weighing sensor, in units of... Measurement accuracy ; The density of a fluid is the density of water at room temperature. ; The time taken for traffic collection, in units of Timing accuracy .

5. The efficient detection and calibration method for a flowmeter based on gravitational potential energy according to claim 4, characterized in that, In S4, the opening of the servo ball valve II of the flow regulation and calibration unit is adjusted. To achieve the target flow rate regulation, the relationship between the opening degree of servo ball valve II and the flow rate satisfies formula (5): ； in, This is an opening-flow function, without units. The opening degree of servo ball valve II, with a value range of... Adjustment precision ; Obtained by linear fitting method , This is the flow gain coefficient, in units of... ; The zero-biased flow coefficient, in units of ; and All were calibrated using multiple sets of opening-flow experimental data.

6. The efficient detection and calibration method for a flowmeter based on gravitational potential energy according to claim 5, characterized in that, The test calibration results of the flow meter under test in S5 are obtained through relative error. The relative error is determined by formula (6): ； in, The relative error of the flow meter under test is expressed in units of _____. ; The target flow rate determined for S4, in units of ; The real-time measurement value of the flow meter under test, in units of ; Preset tolerance ,when When the flow meter under test is deemed qualified, it is considered qualified. If the error value is not found, the flow meter under test is deemed unqualified and the error value is recorded.

7. The efficient detection and calibration method for a flowmeter based on gravitational potential energy according to claim 6, characterized in that, The adjustable height water tank is equipped with a stable liquid level baffle, which is vertically arranged on one side of the water inlet inside the water tank.

8. The efficient detection and calibration method for a flowmeter based on gravitational potential energy according to claim 7, characterized in that, S4 timing And in Continuous collection within a time period Value, sampling interval Take the average , For the first The mass measurement value in seconds is substituted into formula (4) to calculate the actual flow rate. Reduce the impact of random errors; In step (5), the water circuit is switched using an electrically controlled directional valve, and the switching time is... After switching, a stable period of time is required. Samples were collected after the fluid flow stabilized. This avoids measurement deviations caused by switching disturbances.

9. The efficient detection and calibration method for a flowmeter based on gravitational potential energy according to claim 8, characterized in that, The test calibration result of the flow meter under test in S5 is determined by the relative error δ, which is calculated by formula (6): ； in, The relative error of the flow meter under test is expressed in % (%). The target flow rate is defined in S4, in m³ / h. This is the real-time measurement value of the flow meter under test, in m³ / h. Preset tolerance The judgment rule is as follows: when When the flow meter under test is deemed qualified, it is then determined that the flow meter is qualified. when If the error occurs, it is deemed unqualified and the error value is recorded.

10. The efficient detection and calibration method for a flowmeter based on gravitational potential energy according to claim 9, characterized in that, The adjustable height water tank is equipped with a vertically arranged stabilizing liquid level baffle, the installation requirements of which are as follows: high , : Distance from the top of the baffle to the bottom of the water tank, unit: mm; horizontal distance Distance from the water inlet; The performance of the baffle is verified by formula (7): ； Require: ; The peak / trough value of the liquid level within 10 seconds after the baffle buffer is applied, in mm. Baffle calibration steps: Measure the initial distance ; Fully open servo ball valve I for water replenishment, record fluctuations on both sides of the baffle. Inlet side Water outlet side; like ,according to Increase the adjustment step by 10mm until... .

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