Study On Acoustic Observation Method Of Underwater Gas Escape

Underwater gas escape phenomenon widely exists in nature and industrial environment,and it’s commonly found in the exploration,development,and transportation links of the offshore oil and gas industry.Gas escape generated by cold seep is the current research hotspot.With the depletion of coal and petroleum,the natural gas resources have received universal attention.Underwater gas escape is often the beacon of ocean natural gas deposits.Research and investigation of it will help effective exploration of related resources.So the underwater gas escape phenomenon has important research and application value.Acoustic method is an important way in the investigation of the underwater gas escape phenomenon.The visual observation of sonar is an intuitive and efficient survey method.Its work modes mainly include flight-type observation and in-situ observation.Acoustic observations of underwater gas escape mainly use the bubble plumes formed in the water by the escaping gas.The acoustic scattering properties of the bubble plume allow it to be detected and recorded by sonar equipment.In this paper,firstly,describe the acoustic observation mechanism of the underwater gas escape phenomenon.According to the main acoustic observation feature of the underwater gas escape phenomenon,the bubble plume,discuss the characteristics of acoustic scattering,target intensity and other characteristics of the bubble and bubble group.Simulate the distribution of the bubble groups in the stream and the sonar observation effect of the plume.Summarize the sonar observation characteristics of the bubble plume.Based on the theory of acoustic emission from underwater gases,summarize the sonar equipments commonly used in underwater navigation and in-situ acoustic surveys,and analyze their working methods and application conditions.After that,carry out a sonar observation experiment of single-beam sonar flight-type and multi-beam sonar in-situ underwater bubble bubbling.According to the characteristics of plume acoustic image,process the experimental data by image enhancement,submarine line detection,image segmentation,etc.Analyze the observation effect.Then,based on the in situ observation data,process a stereo image of the bubble plume.This thesis combines theory with experiment and provides theoretical and technical support for the practical application of underwater gas escape acoustics observation.