Design Of Underwater Towed System Based On CSEM And Research On Its Hydrodynamic Characteristics

With the continuous development of the world economy, global oil consumption is increasing year by year. Especially in recent years, oil became one of the factors that restrict the development of our country’s economy. So our country’s oil reserves have been rising to a strategic reserve level. The present situation of the oil industry of our country is that the oil output on land is difficult to increase. So it is urgent to find new oil resources to meet the needs of economic development.Our country is vast in sea area and abounds in marine oil resources. Offshore oil exploitation has become an important supplement of China’s oil consumption. As a mature oil exploration technology, Seismic technology is widely applied to onshore oil exploration and in shallow sea. With the development of oil extraction technologies, offshore oil exploitation technology gradually transit from shallow to deep sea.As a new non-seismic technology of marine oil and gas exploitation, CSEM (Marine Controlled Source Electromagnetic Methods) has been widely applied in marine exploitation for it has the advantages that free from the limitation of the sea area. The underwater towed system load the signal receiver unit based on CSEM, so its hydrodynamics performance directly affects the signal quality of CSEM device. This thesis focuses on the optimization design of the main carrier and appendages of the underwater towed system based on CSEM, and the analysis of its hydrodynamic performance. The main research content is as follows:(1) Referencing the current domestic and foreign research status on the underwater towed system, the general design goal, design solutions and optimization method of the underwater towed system are produced.(2) According to the measure parameters of the design of the main carrier, the main carrier of the underwater towed system is designed. By using CFD software, hydrodynamic analysis of the main carriers with different line-type is conducted. And the hydrodynamic characteristics of the main carrier are optimized. In addition, Appendages of the underwater towed system are designed and their hydrodynamic characteristics are optimized.(3) The static analysis of the underwater towed system is studied. The relative position between the center of gravity and the center of buoyancy of the underwater towed system is calculated by the quality evaluation function of three-dimensional software, so its balance and stability can been analyzed. The whole hydrodynamic of the underwater towed system is simulated, so hydrodynamic characteristics and self-regulation are analyzed according to the simulation result.(4) The flume experiment of the principle model of the underwater towed system, the large tank test and the sea trial of the engineering prototype are conducted to verify the effectiveness of the theoretical calculation and CFD analysis results.The theoretical study, CFD hydrodynamic analysis, model test and the sea trial of the engineering prototype of the underwater towed system a based on CSEM are conducted. The optimization design and hydrodynamic analysis of its main carrier and appendage are carried out to provide some conference for engineering usage of the underwater towed system based on CSEM.