Study on acoustic response law of oil-water two-phase flowin horizontal wells

Distributed acoustic sensing (DAS) technology has been widely adopted for dynamic monitoring of horizontal well production. However, the downhole acoustic signals are characterized by complexity and strong interference, Currently, the understanding of the acoustic response laws of oil-water two-phase flow in horizontal wells is still insufficient, and most existing studies remain at the level of qualitative interpretation. Therefore, the quantitative evaluation of the production profile of horizontal reservoir wells by means of DAS data remains a major technical challenge at present. In this study, through laboratory physical simulation experiments, the effective amplitude-frequency features of DAS data were extracted under different production rates, water cuts, and crude oil viscosities in horizontal wells. The acoustic response laws of oil-water two-phase flow in horizontal wells were analyzed; the relationship curves between DAS acoustic wave energy and wellbore flow velocity were plotted, and a model library for the relationship between DAS acoustic wave energy and wellbore flow velocity in horizontal wells with oil-water two-phase flow was established through data regression. This achievement enables the quantitative characterization of the relationship between wellbore flow velocity and DAS response under different simulated conditions, providing a model basis for the inversion modeling of DAS in oil-water two-phase monitoring and offering new technical approaches to address the quantitative interpretation of horizontal well production profiles.