井内瞬态波动压力分析

本文用混合隐式特征线法求解了井内流道中的瞬态波动压力问题，给出了弹性管和可压缩流体在井内各流道组合的压力波波动方程和定解条件。文中对运动管柱(钻柱，套管)在常规井身结构内的各流道组合进行了合理的划分，得出了各种情况下瞬态压力的数值解。本文瞬态波动压力计算结果比过去通用的稳态波动压力计算值更符合井内实际，因此用本文的方法能更准确地计算井内波动压力及确定合理起下钻速度。

ANALYSIS OF TRANSIENT SURGE PRESSURE IN A DRILLING WELL

By using the combined implicit characteristic line method，the calculation of the transient surge pressure in the flow conduit of a drilling well has been resolved in this paper, The dynamic wave equation and the definite solution conditions of a compressive fluid in different flow conduits of elastic pipes in a well have also been derived.Different combinations of pipe-casing flow conduits in a drilling well are defined，and the numerical solution in each condition has been obtained Compared with the steady surge pressure calculation method, the transient method more closely coinsides with the actual hole condition，so that surge pressure and the rational velocity for pulling and running pipes be calculated more precisely by the method given here.