海洋钻井隔水管的动力响应

Dynamic response of riser system in marine drilling

海洋钻井隔水管在交变载荷波浪力作用下发生振动，从而偏离原来的位置，严重时可使钻具遭到破坏，造成钻井中断。采用泛函变分法导出了隔水管的振动微分方程。利用微分方程和边界条件可确定动力响应的通式，将通式代入泛函并求极值，即可得出具体条件下隔水管的动力响应。东海水深２００米，海浪最大波高１５米，周期１３秒。按这种极限海况，应用上述方法对在东海作业的“勘探３号”隔水管的动力响应进行了计算，结果表明，该隔水管中上部距海底１４２米处有最大振动位移３．０６米。

Vibration and offset of riser system in marine drilling under the alternating action of wave force, if terrible, may cause failure of drilling tools and break-off of drilling. The differential equation for the vibration of the riser system is derived by means of functional calculus of variation. The general formula for the dynamic response can be established by the differential equation and the boundary condition, and the dynamic response under a certain condition can be obtained by substituting the general formula into the functional and evaluating the extreme value. And an example of calculation is presented.