Anti-vibration Performance Analysis And Optimization For A Logging While Drilling Neutron Generator Of Black High-voltage

Oil is an essential energy to national development and people's living, its demand constantly increasing. In order to guarantee the sustainable development of energy supply and economic, on the one hand to find new energy to replace oil, on the other hand to speed up the study of oil exploration and extraction technologies. At present the grade of oil and gas resources in our country is getting worse, exploration and development are more and more difficult. Conventional well logging technology has been hard to complete the current oil production task. Pulsed neutron logging technology can not only determine reservoir remaining oil saturation distribution and adjustment of injection-production plan, but also can enhance the recovery efficiency of oil and gas. Logging while drilling(LWD) is accompanied by severe vibration in the process of logging and transportation which often leads the instrument can't work normally. In order that the pulse neutron logging technology is applied to LWD as soon as possible, this paper will analyze the anti-vibration performance of LWD neutron generator of Black High-voltage which applies this technology, then find out the reasons why vibration resistance of the structure is insufficient, make its original structure improvement and optimization design, so that the final structure can meet the required level of vibration. Specific works as follows:1. Researching on the finite element analysis software simulation and optimization techniques combined with Solid Works and ANSYS Workbench design techniques. The technology of data transmission between CAD and CAE is discussed,then research the work that is done when LWD neutron generator model is simplified and repaired before the simulation analysis. The pair of contact set and post-processing techniques in AWE is discussed, and applies these techniques for neutron generator model. The collaborative simulation for optimized design technology between SW and AWE is studied and realize the synchronous updating of the model and the parameters transmission between SW and AWE, and an example is done to verify the feasibility and accuracy of the optimization techniques.2. The modal analysis of pre-compression and random vibration analysis in three directions are analyzed for the original LWD neutron generator. To extract the displacement of the structure and the root mean square of acceleration response for the key sample point under random vibration, make sure that the original model cannot meet the anti-vibration requirements of logging tools and find out the reason. The original structure of the neutron generator topology is improved according to the analysis result of the front,and the improved model is analyzed, including the modal analysis, random vibration analysis and harmonic response analysis.3. The optimization design of the improved LWD neutron generator and the usability analysis of the test fixture are completed. In order to further improve the anti-vibration performance of the structure, the mathematical model of Neutron generator's structure optimization design is established. Adaptive single-objective is used to complete the optimization design whose objective function is the second fixed frequency of the structure, to make the anti-vibration performance improve further. The usability analysis of the test fixture that is designed by the third-party is analyzed.