What is correlation? Precise water leak location with Digital Signal Processing
Correlation is a method for finding and pinpointing leaks in pipes.
A leak in a pipe under pressure creates noise that travels along the pipe, its contents, and through the surrounding ground.
When two highly sensitive microphones are attached to a pipe with a leak betwen them the sound from the leak takes longer to travel to the microphone furthest from the leak, the “time delay” or ∆t.
Utilising this and other known information (pipe diameter, material and length), the exact leak position can be automatically calculated by the correlator SeCorrPhon® AC06
Two highly sensitive microphones are attached by magnet, or valve adaptors, to suitable listening positions such as hydrants, valves, the pipe walls or even directly into the water column using hydrophone sensors. The leak must be between the two microphones. As long as the leak noise can be “heard” and recognised by both microphones (correlated) the SeCorrPhon AC 06 can process and analyse the resulting information.
The sounds picked up by the microphones are transmitted via two powerful 500 mW radio transmitters to the lightweight central processing unit SeCorrPhon AC 06 Digital Signal Processor where the noise information is quickly analysed & the resulting leak position is displayed both graphically and numerically, as metres to the leak from each sensor.