Method for removing bubble interference from ultrasonic water meter

Abstract

This invention provides a method for removing air bubble interference using an ultrasonic water meter, comprising: S1: data acquisition; S2: detection and alarm: determining the number of re-detection times T for air bubbles. e Does it exceed the re-detection threshold T? n It performs multi-condition judgment to determine whether bubbles exist, and detects the original flow rate Q0 and the bubble alarm count A. w S3: Calculate flow rate: Calculate the bubble alarm count A obtained from S2. w This is converted into a bubble count C, and combined with a set bubble count threshold C. n The actual flow rate Q is obtained through corrective calculations. This technical solution first identifies any abnormality in ultrasonic value interruption, coarse-calculated waveform width, or sleep time as a bubble, issuing a bubble warning, then re-detects the head, and repeats the detection multiple times until the re-detection threshold T is exceeded. n Only when the bubbles are large or located directly below the transducer will the system detect no water, thus avoiding misjudging the situation and triggering a no-water alarm. This also helps to improve the accuracy of flow measurement by calculating the actual flow rate based on the detected bubble data.

Description

Technical Field

[0001] This invention relates to the field of ultrasonic water meter data processing technology, and in particular to a method for removing air bubble interference from ultrasonic water meters. Background Technology

[0002] During the use of ultrasonic water meters, air bubbles can significantly affect the propagation path, attenuation characteristics, and measurement accuracy of ultrasonic signals. Although existing technologies have optimization solutions for air bubble interference, when air bubbles float within the acoustic path of the ultrasonic transducer, especially large air bubbles or air bubbles located directly below the transducer, they can directly block the ultrasonic propagation path, causing signal interruption. This usually results in a direct determination of no water, leading to a high false alarm rate for no water and poor accuracy in measuring water volume. Summary of the Invention

[0003] To achieve the above objectives, the present invention adopts the following technical solution: A method for removing air bubble interference in an ultrasonic water meter includes the following steps: S1: Data Acquisition: The system initially sets the sleep time; the ultrasonic signal GP2, the coarse value of the ultrasonic signal GP2, the wave width, and the flight time are acquired via the ultrasonic water meter, and the ultrasonic propagation time difference Δt is calculated; then the normal thresholds for the sleep time, the coarse value of the ultrasonic signal GP2, the wave width, and the flight time are set respectively.

[0004] Furthermore, S1: Data collection includes the following sub-steps: S11: Set Sleep Time: The sleep time is a blind period after the ultrasonic wave is emitted, during which the chip or software shields the receiver to avoid aftershocks, mechanical ringing, and crosstalk signals. It is calibrated at the factory according to the water meter diameter, flow channel length, and transducer parameters. S12: Acquire ultrasonic signal GP2: The effective echo indicator signal output by the transducer in the ultrasonic water meter is the ultrasonic signal GP2. S13: Calculation of coarse value of ultrasonic signal GP2: At the moment of ultrasonic emission, the internal timer of the chip starts counting synchronously. When a valid echo signal of GP2 is generated, the timer immediately latches the current count value; the chip converts the count value into a time value, which is the coarse value of GP2. S14: Obtaining Wavewidth: Wavewidth is the duration of the effective echo signal of GP2. Capture the first effective rising edge of the ultrasound signal GP2 and record the start time t1; capture the last effective edge or the end edge of the echo of the ultrasound signal GP2 and record the end time t2; the time difference between the two is the wavewidth, and the specific calculation formula is: Wavewidth = t2 - t1; S15: Obtaining flight time: The flight time t in the downstream direction is measured by alternating transmission and reception using a pair of ultrasonic transducers. 顺 and the flight time t in the opposite direction 逆 ; S16: Calculate the ultrasonic propagation time difference Δt: The ultrasonic propagation time difference Δt is the time it takes for an ultrasonic wave to travel from the transmitting transducer to the receiving transducer; the specific calculation formula is: Δt = t 逆 -t 顺 .

[0005] S2: Detection and Alarm: Determine the number of bubble re-detection attempts (T) e Does it exceed the re-detection threshold T? n It performs multi-condition judgment to determine whether bubbles exist, and detects the original flow rate Q0 and the bubble alarm count A. w .

[0006] Furthermore, S2: Detection and alarm includes the following sub-steps: S21: Determine the number of bubble re-inspections T e Does it exceed the re-detection threshold T? n A detection cycle consists of the period from triggering bubble detection to completing a full waterless alarm determination or flow output and terminating the detection. The number of bubble re-detections in each cycle is T. e Initially set to 0, bubble alarm count A w Initially set to 0, if the re-detection threshold T is exceeded. n Then proceed with S22: No water or abnormal alarm. If the re-detection threshold T is not exceeded... n Then proceed to S23: flow detection and bubble head finding.

[0007] Furthermore, the re-detection threshold T n Set to 10-50 times.

[0008] S22: No water or abnormal alarm: If the re-detection threshold T is exceeded. n The system outputs the true state and then determines whether the beamwidth and flight time are within the normal threshold. If they are within the normal threshold, it is determined that there is no abnormality and the current round of detection ends directly. If they are not within the normal threshold, it is determined that there is an abnormality, triggers an abnormal no-water alarm, and ends the current round of detection.

[0009] S23: Flow detection: If the re-detection threshold T is not exceeded n If the ultrasound signal GP2, waveform width, and sleep time are all normal, then subsequent flow rate detection is performed to obtain the original flow rate value Q0; if it does not exceed the re-detection threshold T n However, if any of the ultrasound signal GP2, waveform width, or sleep time is abnormal, the bubble alarm will be activated, and the bubble alarm count A will be increased. w Add 1, the number of re-examinations T e Add 1, return to S21 for judgment, and start looking for the head again.

[0010] Furthermore, S23: Traffic detection includes the following sub-steps: S231: Determine if the interruption of the ultrasonic signal GP2 has timed out. If the interruption of the ultrasonic signal GP2 has timed out, activate the bubble alarm and simultaneously count the bubble alarm A. w Add 1, the number of re-examinations T e Add 1, return to S21 for judgment, and find the head again; if the interruption of the ultrasonic signal GP2 has not timed out, continue the detection S232.

[0011] S232: Determine if the coarse value of the ultrasound signal GP2 is abnormal. If the coarse value of the ultrasound signal GP2 exceeds the normal threshold, it is determined to be abnormal and the bubble alarm is activated. At the same time, the bubble alarm count A is also activated. w Add 1, the number of re-examinations T e Add 1, return to S21 for judgment, and find the head again; if the coarse value calculation of the ultrasonic signal GP2 is normal, continue the detection S233.

[0012] S233: Determine if the pulse width and sleep duration are abnormal. If the pulse width and sleep duration exceed the normal threshold, it is considered abnormal, the bubble alarm is activated, and the bubble alarm counter A is started simultaneously. w Add 1, the number of re-examinations T e Add 1, return to S21 for judgment, and find the head again; if the waveform width and sleep time are normal, continue to S234.

[0013] By simultaneously detecting flow rate and identifying bubble heads, the detection process can be made more efficient.

[0014] S234: Combine the ultrasonic propagation time difference Δt obtained from S1 to calculate the original flow rate Q0.

[0015] Furthermore, the specific formula for calculating the original flow rate Q0 is: Q0=k⋅Δt; where: k is the inherent calibration coefficient of the water meter, which is related to the flow channel structure and the length of the acoustic path; the ultrasonic propagation time difference Δt is obtained by measuring the ultrasonic water meter.

[0016] Before flow detection, the stability of the ultrasonic signal GP2, waveform width, and sleep time is verified to eliminate interference from non-bubble factors such as signal distortion and module failure, ensuring the reliability of the original flow value Q0 and providing high-quality basic data for subsequent bubble counting and flow correction.

[0017] S24: Bubble Alarm Statistics and Output: Determine if there are any abnormal situations and output the number of bubble alarms.

[0018] Furthermore, S24: Bubble alarm statistics and output includes the following sub-steps: S241: Determine the bubble alarm count A w If the value is greater than 0, and the ultrasound signal GP2, waveform width, and sleep time are all normal, then reduce the bubble alarm count A. wIf not, proceed to S242; otherwise, proceed directly to S242. S242: Determine the bubble alarm count A w If the value is 0, clear the bubble alarm and end the current detection round; otherwise, end the current detection round directly and output the bubble alarm count A. w .

[0019] When the bubbles are large or located directly below the transducer, the existing method will directly interpret it as a lack of water and trigger a water shortage alarm instead of a bubble alarm, providing incorrect information and misleading operators. This also causes the instantaneous flow rate to be reset to zero, resulting in a significant error compared to the actual flow rate. This method sets a re-detection threshold T. n When the bubble is large or located directly below the transducer, it is first identified as a bubble. Then, by repeatedly re-locating the transducer, it is determined whether it is indeed a large bubble or no water, and then the corresponding alarm is issued. The increased number of re-locating steps allows for the measurement of more flow rates even when there are bubbles, making the measurement more accurate.

[0020] This system ensures the cumulative validity of counts in continuous bubble scenarios, while also allowing the count to gradually return to a reasonable range through attenuation in scenarios where a bubble passes instantaneously and no new anomalies are present. This avoids long-term residual alarms caused by a single bubble and reduces the probability of false continuous alarms. If other anomalies exist (such as abnormal ultrasonic signal GP2 or waveform width), count attenuation will not be triggered, ensuring the reliability of alarm counts when there are system hardware or signal anomalies and avoiding missed anomaly detection due to erroneous attenuation.

[0021] When A w When the alarm decays to 0, the bubble alarm is actively cleared, forming a complete closed loop of alarm triggering, dynamic decay, count resetting, and cancellation. This allows for automatic recovery to normal operation without manual intervention, reducing interference from invalid alarms and lowering troubleshooting costs for maintenance personnel. If A... w If the count is not zeroed, it continues to output a count, which not only provides a quantitative basis for the degree of bubble accumulation in the subsequent flow correction process, but also allows maintenance personnel to perceive the duration and severity of bubbles through count changes, and helps to predict potential flow channel or water quality problems.

[0022] S3: Calculate flow rate: Convert the bubble alarm count A obtained in S2... w This is converted into a bubble count C, and combined with a set bubble count threshold C. n After performing a correction calculation, the actual flow rate Q is obtained.

[0023] Furthermore, S3: Calculating the flow rate includes the following sub-steps: S31: Verify bubble alarm: Initially set bubble count C=0, bubble count threshold C n ; Detect the presence of air bubbles and trigger an alarm; initially set the bubble count C=A. w .

[0024] Furthermore, the bubble counting threshold C n Set to 5~10.

[0025] S32: Correction Calculation: The flow rate is corrected based on the degree of interference from bubbles. If there is no bubble alarm, C=0, and it is determined that there is no bubble interference, and the actual flow rate Q=the original flow rate Q0; if the bubble count C exceeds the bubble count threshold C... n C > C n If this is determined to be a large amount of bubble interference, the system enters a zero-reporting state and then resets the bubble count; if the bubble count C does not exceed the bubble count threshold C... n C≤C n If the value is slightly affected by bubble interference, the static value Q is corrected using the scaling factor K. s To obtain the actual traffic flow Q; The specific formula for calculating the actual flow rate Q is: Actual flow rate Q = K⋅Q s ; Where: K is the proportionality coefficient, and the specific calculation formula is: proportionality coefficient ; static value Q s The true, stable flow rate within the pipeline before bubble interference occurs is the flow rate value locked at the onset of a bubble event.

[0026] The calculation is adjusted according to different scenarios. When C=0, the original flow rate Q=Q0 is directly taken to avoid meaningless calculations and ensure metering efficiency and real-time performance under normal operating conditions; when C>C... n The system triggers a zero-reporting state to prevent severe flow distortion caused by a large number of bubbles and to prevent erroneous measurement data from interfering with the results; simultaneously, it resets the bubble count, allowing the system to quickly return to the initial detection state and improving its self-recovery capability in the face of sudden heavy bubble activity; when C≤C n At that time, the static value Q is locked by the proportional coefficient K. s The core advantage of this correction lies in the dynamic change of the K value with the bubble count C, making the flow correction magnitude highly positively correlated with the degree of bubble interference, thus avoiding correction errors caused by fixed parameters; the static value Q... s Locking in a stable flow rate before bubbles occur avoids the impact of real-time fluctuations during the correction process, ensuring that the measurement results under mild bubbles are closer to the true value.

[0027] Compared with the prior art, the beneficial effects of the present invention are as follows: when any abnormality occurs in ultrasound value interruption, coarse value calculation waveform width, or sleep time, it is first identified as an air bubble, an air bubble warning is issued, and then the head is re-identified, and multiple tests are performed until the re-detection threshold T is exceeded. nOnly when bubbles are large enough to be considered dry can a waterless state be determined, avoiding misjudgments and alarms caused by large bubbles or bubbles blocking the bottom of the transducer, which could mislead staff and affect flow measurement accuracy. A precise bubble count is obtained and then compared with the bubble count threshold C. n After comparison, the original data is processed according to different cases, and the interference of bubbles in the flow calculation is removed after the calculation is corrected, so that the measurement is more accurate. Attached Figure Description

[0028] Figure 1 This is a flowchart of S2 in Embodiment 1 of the present invention; Figure 2 This is a flowchart of S2 and S3 in Embodiment 1 of the present invention. Detailed Implementation

[0029] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings: A method for removing air bubble interference in an ultrasonic water meter includes the following steps: S1: Data Acquisition: The system initially sets the sleep time; the ultrasonic signal GP2, the coarse value of the ultrasonic signal GP2, the wave width, and the flight time are acquired via the ultrasonic water meter, and the ultrasonic propagation time difference Δt is calculated; then the normal thresholds for the sleep time, the coarse value of the ultrasonic signal GP2, the wave width, and the flight time are set respectively.

[0030] Furthermore, S1: Data collection includes the following sub-steps: S11: Set Sleep Time: The sleep time is a blind period after the ultrasonic wave is emitted, during which the chip or software shields the receiver to avoid aftershocks, mechanical ringing, and crosstalk signals. It is calibrated at the factory according to the water meter diameter, flow channel length, and transducer parameters. S12: Acquire ultrasonic signal GP2: The effective echo indicator signal output by the transducer in the ultrasonic water meter is the ultrasonic signal GP2. S13: Calculation of coarse value of ultrasonic signal GP2: At the moment of ultrasonic emission, the internal timer of the chip starts counting synchronously. When a valid echo signal of GP2 is generated, the timer immediately latches the current count value; the chip converts the count value into a time value, which is the coarse value of GP2. S14: Obtaining Wavewidth: Wavewidth is the duration of the effective echo signal of GP2. Capture the first effective rising edge of the ultrasound signal GP2 and record the start time t1; capture the last effective edge or the end edge of the echo of the ultrasound signal GP2 and record the end time t2; the time difference between the two is the wavewidth, and the specific calculation formula is: Wavewidth = t2 - t1; S15: Obtaining flight time: The flight time t in the downstream direction is measured by alternating transmission and reception using a pair of ultrasonic transducers. 顺and the flight time t in the opposite direction 逆 ; S16: Calculate the ultrasonic propagation time difference Δt: The ultrasonic propagation time difference Δt is the time it takes for an ultrasonic wave to travel from the transmitting transducer to the receiving transducer; the specific calculation formula is: Δt = t 逆 -t 顺 .

[0031] S2: Detection and Alarm: Determine the number of bubble re-detection attempts (T) e Does it exceed the re-detection threshold T? n It performs multi-condition judgment to determine whether bubbles exist, and detects the original flow rate Q0 and the bubble alarm count A. w .

[0032] Furthermore, S2: Detection and alarm includes the following sub-steps: S21: Determine the number of bubble re-inspections T e Does it exceed the re-detection threshold T? n A detection cycle consists of the period from triggering bubble detection to completing a full waterless alarm determination or flow output and terminating the detection. The number of bubble re-detections in each cycle is T. e Initially set to 0, bubble alarm count A w Initially set to 0, if the re-detection threshold T is exceeded. n Then proceed with S22: No water or abnormal alarm. If the re-detection threshold T is not exceeded... n Then proceed to S23: flow detection and bubble head finding.

[0033] Furthermore, the re-detection threshold T n Set to 20 times.

[0034] S22: No water or abnormal alarm: If the re-detection threshold T is exceeded. n The system outputs the true state and then determines whether the beamwidth and flight time are within the normal threshold. If they are within the normal threshold, it is determined that there is no abnormality and the current round of detection ends directly. If they are not within the normal threshold, it is determined that there is an abnormality, triggers an abnormal no-water alarm, and ends the current round of detection.

[0035] S23: Flow detection: If the re-detection threshold T is not exceeded n If the ultrasound signal GP2, waveform width, and sleep time are all normal, then subsequent flow rate detection is performed to obtain the original flow rate value Q0; if it does not exceed the re-detection threshold T n However, if any of the ultrasound signal GP2, waveform width, or sleep time is abnormal, the bubble alarm will be activated, and the bubble alarm count A will be increased. w Add 1, the number of re-examinations T e Add 1, return to S21 for judgment, and start looking for the head again.

[0036] Furthermore, S23: Traffic detection includes the following sub-steps: S231: Determine if the interruption of the ultrasonic signal GP2 has timed out. If the interruption of the ultrasonic signal GP2 has timed out, activate the bubble alarm and simultaneously count the bubble alarm A. w Add 1, the number of re-examinations T e Add 1, return to S21 for judgment, and find the head again; if the interruption of the ultrasonic signal GP2 has not timed out, continue the detection S232.

[0037] S232: Determine if the coarse value of the ultrasound signal GP2 is abnormal. If the coarse value of the ultrasound signal GP2 exceeds the normal threshold, it is determined to be abnormal and the bubble alarm is activated. At the same time, the bubble alarm count A is also activated. w Add 1, the number of re-examinations T e Add 1, return to S21 for judgment, and find the head again; if the coarse value calculation of the ultrasonic signal GP2 is normal, continue the detection S233.

[0038] S233: Determine if the pulse width and sleep duration are abnormal. If the pulse width and sleep duration exceed the normal threshold, it is considered abnormal, the bubble alarm is activated, and the bubble alarm counter A is started simultaneously. w Add 1, the number of re-examinations T e Add 1, return to S21 for judgment, and find the head again; if the waveform width and sleep time are normal, continue to S234.

[0039] S234: Combine the ultrasonic propagation time difference Δt obtained from S1 to calculate the original flow rate Q0.

[0040] Furthermore, the specific formula for calculating the original flow rate Q0 is: Q0=k⋅Δt; where: k is the inherent calibration coefficient of the water meter, which is related to the flow channel structure and the length of the acoustic path; the ultrasonic propagation time difference Δt is obtained by measuring the ultrasonic water meter.

[0041] S24: Bubble Alarm Statistics and Output: Determine if there are any abnormal situations and output the number of bubble alarms.

[0042] Furthermore, S24: Bubble alarm statistics and output includes the following sub-steps: S241: Determine the bubble alarm count A w If the value is greater than 0, and the ultrasound signal GP2, waveform width, and sleep time are all normal, then reduce the bubble alarm count A. w If not, proceed to S242; otherwise, proceed directly to S242. S242: Determine the bubble alarm count A w If the value is 0, clear the bubble alarm and end the current detection round; otherwise, end the current detection round directly and output the bubble alarm count A. w .

[0043] S3: Calculate flow rate: Convert the bubble alarm count A obtained in S2... w This is converted into a bubble count C, and combined with a set bubble count threshold C. n After performing a correction calculation, the actual flow rate Q is obtained.

[0044] Furthermore, S3: Calculating the flow rate includes the following sub-steps: S31: Verify bubble alarm: Initially set bubble count C=0, bubble count threshold C n ; Detect the presence of air bubbles and trigger an alarm; initially set the bubble count C=A. w .

[0045] Furthermore, the bubble counting threshold C n Set it to 8.

[0046] S32: Correction Calculation: The flow rate is corrected based on the degree of interference from bubbles. If there is no bubble alarm, C=0, and it is determined that there is no bubble interference, and the actual flow rate Q=the original flow rate Q0; if the bubble count C exceeds the bubble count threshold C... n C > C n If this is determined to be a large amount of bubble interference, the system enters a zero-reporting state and then resets the bubble count; if the bubble count C does not exceed the bubble count threshold C... n C≤C n If the value is slightly affected by bubble interference, the static value Q is corrected using the scaling factor K. s To obtain the actual traffic flow Q; The specific formula for calculating the actual flow rate Q is: Actual flow rate Q = K⋅Q s ; Where: K is the proportionality coefficient, and the specific calculation formula is: proportionality coefficient ; static value Q s The true, stable flow rate within the pipeline before bubble interference occurs is the flow rate value locked at the onset of a bubble event.

[0047] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A method for removing air bubble interference using an ultrasonic water meter, characterized in that: Includes the following steps: S1: Data Acquisition: The system initially sets the sleep time; the ultrasonic signal GP2, the coarse value of the ultrasonic signal GP2, the wave width, and the flight time are acquired via the ultrasonic water meter, and the ultrasonic propagation time difference Δt is calculated; then the normal thresholds for the sleep time, the coarse value of the ultrasonic signal GP2, the wave width, and the flight time are set respectively. S2: Detection and Alarm: Determine the number of bubble re-detection attempts (T) e Does it exceed the re-detection threshold T? n It performs multi-condition judgment to determine whether bubbles exist, and detects the original flow rate Q0 and the bubble alarm count A. w ; S3: Calculate flow rate: Convert the bubble alarm count A obtained in S2... w This is converted into a bubble count C, and combined with a set bubble count threshold C. n After performing a correction calculation, the actual flow rate Q is obtained.

2. The method for removing air bubble interference using an ultrasonic water meter as described in claim 1, characterized in that: S1: Data collection includes the following sub-steps: S11: Set Sleep Time: The sleep time is a blind period after the ultrasonic wave is emitted, during which the chip or software shields the receiver to avoid aftershocks, mechanical ringing, and crosstalk signals. It is calibrated at the factory according to the water meter diameter, flow channel length, and transducer parameters. S12: Acquire ultrasonic signal GP2: The effective echo indicator signal output by the transducer in the ultrasonic water meter is the ultrasonic signal GP2. S13: Calculation of coarse value of ultrasonic signal GP2: At the moment of ultrasonic emission, the internal timer of the chip starts counting synchronously. When a valid echo signal of GP2 is generated, the timer immediately latches the current count value; the chip converts the count value into a time value, which is the coarse value of GP2. S14: Obtaining Wavewidth: Wavewidth is the duration of the effective echo signal of GP2. Capture the first effective rising edge of the ultrasound signal GP2 and record the start time t1; capture the last effective edge or the end edge of the echo of the ultrasound signal GP2 and record the end time t2; the time difference between the two is the wavewidth, and the specific calculation formula is: Wavewidth = t2 - t1; S15: Obtaining flight time: The flight time t in the downstream direction is measured by alternating transmission and reception using a pair of ultrasonic transducers. 顺 and the flight time t in the opposite direction 逆 ; S16: Calculate the ultrasonic propagation time difference Δt: The ultrasonic propagation time difference Δt is the time it takes for an ultrasonic wave to travel from the transmitting transducer to the receiving transducer; the specific calculation formula is: Δt = t 逆 -t 顺 .

3. The method for removing air bubble interference using an ultrasonic water meter as described in claim 1, characterized in that: S2: detection and alarm include the following sub-steps: S21: Determine the number of bubble re-inspections T e Does it exceed the re-detection threshold T? n A detection cycle consists of the period from triggering bubble detection to completing a full waterless alarm determination or flow output and terminating the detection. The number of bubble re-detections in each cycle is T. e Initially set to 0, bubble alarm count A w Initially set to 0, if the re-detection threshold T is exceeded. n Then proceed with S22: No water or abnormal alarm. If the re-detection threshold T is not exceeded... n Then proceed to S23: flow detection and bubble head finding; S22: No water or abnormal alarm: If the re-detection threshold T is exceeded. n The system outputs the true state and then determines whether the beam width and flight time are within the normal threshold. If they are within the normal threshold, it is determined that there is no abnormality and the current round of detection ends directly. If they are not within the normal threshold, it is determined that there is an abnormality, triggers an abnormal waterless alarm, and ends the current round of detection. S23: Flow detection: If the re-detection threshold T is not exceeded n If the ultrasound signal GP2, waveform width, and sleep time are all normal, then subsequent flow rate detection is performed to obtain the original flow rate value Q0; if it does not exceed the re-detection threshold T n However, if any of the ultrasound signal GP2, waveform width, or sleep time is abnormal, the bubble alarm will be activated, and the bubble alarm count A will be increased. w Add 1, the number of re-examinations T e Add 1, return to S21 for judgment, and find the head again; S24: Bubble Alarm Statistics and Output: Determine if there are any abnormal situations and output the number of bubble alarms.

4. The method for removing air bubble interference using an ultrasonic water meter as described in claim 3, characterized in that: S23: Flow detection includes the following sub-steps: S231: Determine if the interruption of the ultrasonic signal GP2 has timed out. If the interruption of the ultrasonic signal GP2 has timed out, activate the bubble alarm and simultaneously count the bubble alarm A. w Add 1, the number of re-examinations T e Add 1, return to S21 for judgment, and find the head again; if the ultrasonic signal GP2 interruption has not timed out, continue the detection S232; S232: Determine if the coarse value of the ultrasound signal GP2 is abnormal. If the coarse value of the ultrasound signal GP2 exceeds the normal threshold, it is determined to be abnormal and the bubble alarm is activated. At the same time, the bubble alarm count A is also activated. w Add 1, the number of re-examinations T e Add 1, return to S21 for judgment, and find the head again; if the coarse value calculation of the ultrasonic signal GP2 is normal, continue the detection S233; S233: Determine if the pulse width and sleep duration are abnormal. If the pulse width and sleep duration exceed the normal threshold, it is considered abnormal, the bubble alarm is activated, and the bubble alarm counter A is started simultaneously. w Add 1, the number of re-examinations T e Add 1, return to S21 for judgment, and find the head again; if the waveform width and sleep time are normal, continue to S234; S234: Combine the ultrasonic propagation time difference Δt obtained from S1 to calculate the original flow rate Q0.

5. The method for removing air bubble interference using an ultrasonic water meter as described in claim 3, characterized in that: S24: Bubble alarm statistics and output includes the following sub-steps: S241: Determine the bubble alarm count A w If the value is greater than 0, and the ultrasound signal GP2, waveform width, and sleep time are all normal, then reduce the bubble alarm count A. w If not, proceed to S242; otherwise, proceed directly to S242. S242: Determine the bubble alarm count A w If the value is 0, clear the bubble alarm and end the current detection round; otherwise, end the current detection round directly and output the bubble alarm count A. w .

6. The method for removing air bubble interference using an ultrasonic water meter as described in claim 1, characterized in that: S3: Calculating the flow rate includes the following sub-steps: S31: Verify bubble alarm: Initially set bubble count C=0, bubble count threshold C n ; Detect the presence of air bubbles and trigger an alarm; initially set the bubble count C=A. w . 7.S32: Correction Calculation: The flow rate is corrected based on the degree of interference from bubbles. If there is no bubble alarm, C=0, indicating no bubble interference, and the actual flow rate Q=the original flow rate Q0; if the bubble count C exceeds the bubble count threshold C... n C > C n If this is determined to be a large amount of bubble interference, the system enters a zero-reporting state and then resets the bubble count; if the bubble count C does not exceed the bubble count threshold C... n C≤C n If the value is slightly affected by bubble interference, the static value Q is corrected using the scaling factor K. s To obtain the actual traffic flow Q; The specific formula for calculating the actual flow rate Q is: Actual flow rate Q = K⋅Q s ; in: K is the proportionality coefficient, and the specific calculation formula is: proportionality coefficient ; static value Q s The true, stable flow rate within the pipeline before bubble interference occurs is the flow rate value locked at the onset of a bubble event.

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