可控震源振动器系统不确定性分析

为了解决可控震源施工过程中振动器系统的安全性问题，采用故障树法建立仿真模型。通过失效分析得出各故障单元的失效模式及单元间分布规律，计算出振动器系统的可靠度。开展对该系统敏感性的不确定性分析，得出影响振动器系统可靠性的关键因素为重锤上部密封失效。采用有限元法对其应力场进行模拟仿真。结果表明:随着工作频率的升高，O形圈应力波动越大，密封越容易失效。Von Mises应力随压缩率的增大先减小后增大，随槽口半径的增大而增大；接触应力在一定范围内随压缩率及槽口半径的增大而增大。为振动器的结构优化与可靠性设计提供理论依据，并为油气资源勘探开发的安全作业提供工程应用指导。

Uncertainty analysis of vibroseis vibrator system

In order to solve the safety problems of vibrator system during the construction of vibroseis, a simulation model was established by using the fault tree method. The failure mode of each fault unit and the distribution laws among the units were obtained through failure analysis, and the reliability of vibrator system was calculated. Through the uncertainty analysis on the sensitivity of the system, it was found that the key factor influencing the reliability of vibrator system was the seal failure in the upper part of heavy hammer. The stress field was simulated by using the finite element analysis. The results showed that with the increase of working frequency, the larger the stress fluctuation of O-ring, the more easy failure the seal. The Von Mises stress decreases first and then increases with the increase of compression ratio, and increases with increase of notch radius. The contact stress increases with the increase of compression ratio and notch radius in a certain range. It provides theoretical basis for the structure optimization and reliability design of vibrator, and provides engineering application guidance for the safe operation of oil and gas exploration and development.