中文摘要：

编制了井底钻具组合动力学特性的模拟程序,模拟结果与文献中的结果对比表明,所编模拟程序的模拟结果正确。利用井底钻具组合动力学特性的模拟程序模拟了钻铤形心的径向速度、径向加速度、涡动加速度、涡动速度功率谱以及相图,较全面地反映了井底钻具组合的动力学特性。结果表明：井底钻具组合在特定的情况下可以做规则涡动,更多的是做非规则涡动,没有运动周期;做规则涡动时,钻铤形心的涡动速度较小,其径向速度、径向加速度和涡动加速度均为0。在文中条件下,钻铤形心的涡动速度高达568.73 r/min,远大于规则向后涡动速度（79.41 r/min）,该种状态的出现对钻具组合的导向能力及安全性将造成很大的的影响,值得进一步探讨。

英文摘要：

A program was made using Matlab to investigate the dynamic properties of bottom hole assembly（BHA）,the calculated results agree with reported results.The simulations radial speed,radial acceleration,whirl acceleration,spectrum of whirl speed and phase portrait show the dynamic properties of BHA comprehensively.The result shows that the whirl of BHA can be regular under given conditions,while it is non-regular in most cases.When it is regular,the whirl speed of drilling collar is small with zero radial speed,radial acceleration and whirl acceleration.Under the condition described in this paper,the maximum whirl speed of BHA is 568.73 r/min which is larger than regular back whirl speed of 79.41 r/min.This dynamic property affects the steering ability and the safety of BHA which needs further study.