基于流固耦合钻柱系统动力学模拟.

The nonlinear dynamics of the drilling string system is studied, and the fluid-structure coupling dynamic equation of the drilling string system is established. With the Galerkin truncation method, a set of partial differential equations are diverted into ordinary differential equations. Numerical simulation is carried out by using the Runge-Kutta integration method and the effects of parameters such as pulsating frequency, pulsation amplitude and mass ratio on the dynamic characteristics of the drilling string system are investigated. The results show that there are various dynamic behaviors for the model in different parametric excitation such as periodic motion, quasiperiodic motion, chaotic motion and jump discontinuous phenomenon. Besides, the path from chaotic motion to periodic motion is in the form of period-doubling inverse bifurcation, and the support stiffness can cause a certain change in the inherent characteristics of the system, which has a complex impact on the nonlinear dynamic behavior of the system. [ABSTRACT FROM AUTHOR]