Leak noise correlator

A leak noise correlator is an electronic device used for leak detection and as a leak locator to find leaks in pressurized water or gas lines. Typically, a microphone, acoustic sound sensor, or accelerometer is placed at two or more places in contact with the pipe to detect and record sound emitted by leaks. The sound data is processed through a mathematical algorithm which compares or correlates the speed of sound that the leak noise travels from the point of the leak to each of the sensors. The correlation can then be used to determine the location of the leak. [http://flowmetrix.com/pri_digi.htm]

Leak correlators require accurate information on the materials in which the leak sound is traveling in order to do an accurate correlation. The user normally has to input the size and type of pipe as well as the distances of the loggers from each other. Many standard pipe sizes have known speeds of sound which can be used for the correlation calculation. If the materials are unknown, the speed of sound through the materials will have to be calculated on site to get an accurate leak correlation. Most correlators can also analyze the sound levels and sound frequencies to determine other information about the leak such as the size and severity of the leak or whether it's on the pipe, a valve or hydrant, or in a service line.

Most leak correlators serve two major purposes. First to detect the presence of a leak, second to pinpoint the location of the leak for repair when detected.

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