Detecting leaks in a fluid distribution system

• US 9,939,344 B2
• Filed: 10/25/2013
• Issued: 04/10/2018
• Est. Priority Date: 10/26/2012
• Status: Active Grant

• Current Assignee: Mueller International LLC (Mueller Water Products Incorporated)
• Original Assignee: Mueller International LLC (Mueller Water Products Incorporated)
• Inventors: Bracken, Marc, Yusuf, Shabbir
• Primary Examiner(s): ALKAFAWI, EMAN A
• Application Number:
  US14/063,334
• Publication Number:
  US 20140121999A1
• Time in Patent Office: 1,628 Days
• Field of Search: 702 51, 702 54
• CPC Class Codes: G01M 3/243 for pipes

Abstract

Technologies for detecting leaks in a fluid distribution system are described herein. Historical leak detection information is received from a sensor in the fluid distribution system and collected in a database. A baseline is determined from the historical leak information. Current leak detection information is then received from the sensor and the probability of a leak in the fluid distribution system is determined based on a difference between the current leak detection information and the baseline.

Claims

1. A processor-implemented method comprising the steps of:

receiving, at a processor, current leak detection information comprising an acoustic waveform in a time domain from a first sensor in a fluid distribution system;

calculating, by the processor, threshold levels from a normal baseline waveform, the normal baseline waveform determined from historical acoustic data received from the first sensor;

detecting, by the processor, a transient in a portion of the acoustic waveform by determining that an amplitude of the acoustic waveform exceeds the threshold levels;

upon detecting the transient, completely removing all of the data in the portion of the acoustic waveform from the current leak detection information leaving a gap in the acoustic waveform with a first end and a second end; and

splicing, by the processor, the first and the second end of the gap in the waveform together,

wherein the current leak detection information with the transient removed is utilized by the processor to determine a probability of a leak in the fluid distribution system based on a correlation between the current leak detection information and the normal baseline waveform.

2. The method of claim 1, wherein the current leak detection information comprises time stamp information.

3. The method of claim 1, wherein the current leak detection information is received from a first node in a mesh network communicatively connected to the processor through one or more intermediate nodes.

4. The method of claim 1, wherein the first sensor comprises one from the group consisting of a piezoelectric sensor, an acoustic transducer, a hydrophone, a pressure sensor, and an accelerometer.

5. The method of claim 1, further comprising the step of providing an alarm to an operator system based on the probability of the leak.

6. The method of claim 1, further comprising the step of:

detecting, by the processor, a discontinuity in the acoustic waveform at a position of the removed portion of the acoustic waveform; and

upon detecting the discontinuity, performing, by the processor, a wave smoothing operation of the acoustic waveform to smooth the discontinuity in the acoustic waveform.

7. The method of claim 1, wherein the threshold levels comprise a percentage of an amplitude of the normal baseline waveform.

8. A system for detecting a leak in a fluid distribution system, the system comprising:

a plurality of leak detectors in the fluid distribution system, each leak detector comprising one or more sensors, a processing device, and a communication device, the processing device configured to

receive signal data from the one or more sensors,

process the signal data, and

send the processed signal data via the communication device to a host, the processed signal data comprising an acoustic waveform in a time domain; and

the host comprising a processor, a database, and a communication module, the processor configured to

receive via the communication module a plurality of processed signal data from the plurality of leak detectors,

calculate threshold levels from a normal baseline waveform, the normal baseline waveform determined from historical acoustic data received from the plurality of leak detectors,

detect a transient in a portion of an acoustic waveform from a first leak detector of the plurality of leak detectors by determining an amplitude of the acoustic waveform exceeds the threshold levels, wherein the portion of the acoustic waveform from the first leak detector is a specific time section,

upon detecting the transient in the portion of the acoustic waveform, completely remove all of the data in the portion of the acoustic waveform for the specific time section from the processed signal data for each leak detector from the plurality of leak detectors leaving a gap in the acoustic waveform with a first end and a second end,

splice the first and the second end of the gap in the acoustic waveform together, and

determine from the processed signal data with the transient removed that a leak has occurred in the fluid distribution system based on a correlation between the processed signal data and the normal baseline waveform.

9. The system of claim 8, wherein the processing device is configured to send the processed signal data to the host on a periodic basis.

10. The system of claim 8, wherein the processing device is configured to send the processed signal data to the host in response to receiving a request from the host.

11. The system of claim 8, wherein the processing device is configured to, upon receiving signal data from a first sensor of the one or more sensors indicative of a leak in the fluid distribution system, activate a second sensor of the one or more sensors to collect additional signal data to be sent to the host.

12. The system of claim 11, wherein the second sensor is configured to collect data regarding one or more of a size of the leak and a location of the leak.

13. The system of claim 8, wherein the leak detector comprises an acoustic sensor, a pressure sensor, and a temperature sensor, wherein each of the sensors may be activated by the processing device independently.

14. The system of claim 8, wherein processing the signal data comprises time stamping the signal data.

15. The system of claim 14, where the processing device is further configured to exchange timing information with other of the plurality of leak detectors to synchronize time stamping of signal data between the plurality of leak detectors.

16. The system of claim 8, wherein the processor is further configured to:

detect a discontinuity in the acoustic waveform at a position of the removed portion of the acoustic waveform; and

upon detecting the discontinuity, perform a wave smoothing operation of the acoustic waveform to smooth the discontinuity in the acoustic waveform.

17. An apparatus comprising:

one or more sensors;

a communication device; and

a processing device operatively coupled to the one or more sensors and the communication device and configured to

receive an acoustic waveform in a time domain from the one or more sensors,

determine whether an amplitude of the acoustic waveform exceeds a predetermined threshold, the predetermined threshold calculated from a normal baseline waveform determined from historical acoustic data received from the one or more sensors,

upon determining that the predetermined threshold has been exceeded, completely remove all of the data in a section of the acoustic waveform where the amplitude exceeds the predetermined threshold leaving a gap in the acoustic waveform with a first end and a second end,

splice the first and the second end of the gap in the acoustic waveform together, and

upon splicing the acoustic waveform together, transmit data regarding the acoustic waveform without the removed section to a host via the communication device, the host configured to detect a leak in a fluid distribution system based on a correlation between the acoustic waveform and the normal baseline waveform.

18. The apparatus of claim 17, wherein the processing device is further configured to:

detect a discontinuity in the acoustic waveform at a position of the removed section of the acoustic waveform; and

upon detecting the discontinuity, perform a wave smoothing operation of the acoustic waveform over the removed section to smooth the discontinuity in the acoustic waveform.

19. The apparatus of claim 17, wherein the apparatus is coupled to a distribution main of the fluid distribution system.

20. The apparatus of claim 17, wherein the fluid distribution system comprises a water distribution system and the apparatus is coupled to a hydrant of the water distribution system.