底部钻具组合动力学特性模拟试验方法研究

为了对底部钻具组合(BHA)的动力学特性进行研究,以BHA的运动微分方程为基础,应用相似理论得出了模拟试验参数与现场参数之间的对应关系,设计并建造了BHA动力学特性模拟的试验装置,设计了模拟井筒和模拟BHA,同时考虑了它们之间的摩擦作用,通过模拟试验研究了钻压、钻速、井斜角、稳定器外径及钻柱与井筒之间的摩擦作用对钻头侧向力、转角及运动规律的影响。最后指出,钻井液与钻柱的非线性流固耦合作用对钻柱力学行为有很大的影响,单纯的理论分析仍显不足,有必要通过模拟试验进行深入研究。

Research on the Simulation Test Method for Dynamic Properties of BHA

To conduct research on the dynamic properties of bottomhole assembly(BHA),the corresponding relation between simulation test parameters and field parameters was obtained applying similarity theory on the basis of the BHA differential equation of motion.The simulation test device of BHA dynamic properties was designed and produced.The simulation shaft and BHA were designed.Meanwhile,the friction between them was considered.Through the simulation test the effects of WOB,penetration rate,hole deviation angle,stabilizer's outer diameter and friction between drillpipe and shaft on drilling bit's lateral force,rotation angle and motion law were studied.Finally,it is pointed out that the effect of the nonlinear fluid-solid coupling effect of drilling fluid and drillpipe on the mechanical behavior of drillpipe is remarkable.Only theoretical analysis is not sufficient and it is necessary to make further study through simulation test.