Research on liquid level detection based on acoustic field characteristic of the oil wells

In this paper, a detection method of oil well dynamic fluid level based on the sound field model of the column is presented. In this method, the typical string structure can be analyzed with the pipeline acoustic theory. Moreover, the relationship between the well dynamic fluid level depth and the resonance frequency of the tube sound field is established, according to the sound field characteristic of the column and resonance theory of tube air column, measuring the resonance frequency of the sound field in tube by Fast Fourier Transform (FFT), then liquid level depth of tube will be obtained. The experimental results show that the proposed protocol is practicable, providing a new way for the accurate detection of the well dynamic fluid level depth.