Acoustic propagation and low flow rate leak signal detection using CFAR method

Passive acoustics has been recognized as an important strategy for long-term detection and monitoring of underwater gas leaks in natural sites or in underwater gas pipelines. The ability of an acoustic system to detect underwater gas leaks is primarily controlled by the signal-to-noise ratio (SNR) of bubble sounds. In the current research, it is tried to provide the possibility of detecting the leakage signal with low flow rate and in the presence of strong noise by using the CFAR method. In this regard, "Bellhop" software was used to model the underwater acoustic channel. According to previous researches, the minimum detectable leakage flow rate for the threshold-based detection method is equal to 2 liters per minute (at a maximum distance of 0.5 meters from the leakage location) and the SNR required by this method for detection is also equal to 6 dB. . Considering the lower power of the signal with low flow rate and as a result lower SNR compared to the high rate of leakage current, it is shown in the simulated scenario that by using the CFAR method, the acoustic signal of leakage with low flux can be detected. also identified On the other hand, the performance of the OS-CFAR method is much better than other methods, and it provides the possibility of detecting the leakage signal with low flux even at very low SNR values (up to SNR = -10 dB).