【摘要】 针对深水钻井溢漏复杂工况下温压变化规律认识不清和溢漏层位判断难度大的问题，在分析溢漏循环过程中传热的基础上，考虑井筒环空内的变质量流动对井筒内温压变化影响，建立溢漏循环条件下井筒瞬态温压模型。通过定义环空沿程温差和环空沿程压差的概念，进行溢漏共存工况的模拟分析。结果表明：对于溢漏共存工况，上溢下漏工况的温差整体上大于上漏下溢工况下的温差，而上漏下溢工况的压差整体上大于上溢下漏工况下的压差；裸眼段环空温差突变位置对应着气侵层位，裸眼段环空温差转折位置对应着漏失层位；初始气侵压差越大，井口处环空温差越大；初始漏失压差越大，井口处环空温差越小，且降低的幅度呈增加趋势。更多还原

【Abstract】 In deep water drilling, there are challenges to work out the temperature and pressure variation patterns in wellbore and it is difficult to determine the gas influx(overflow) and drilling fluid loss positions, especially under the complex coexistence of overflow and loss conditions. In this study, a transient wellbore temperature and pressure model under the coexistence of overflow and circulation loss conditions was established, based on heat transfer analysis and accounting for the impact of variable mass flow in wellbore annulus on temperature and pressure changes. The analysis of the gas influx and circulation loss coexistence was conducted by defining and calculating the temperature and pressure differences along the annulus. The simulation results indicate that the temperature difference is generally greater under the condition of upper gas influx and lower circulation loss positions compared to that with upper circulation loss and lower gas influx, while the pressure difference is generally greater under the condition of upper circulation loss and lower gas influx compared to upper gas influx and lower circulation loss. An abrupt change of annular temperature difference in an open hole section mostly corresponds to a gas influx position, while a transition in annular temperature difference in an open hole section corresponds to a circulation loss position. A larger initial gas invasion pressure difference can result in a greater annular temperature difference at the wellhead. As the initial circulation loss pressure difference increases, the annular temperature difference at the wellhead decreases.更多还原