循环钻进过程中井筒温度场新模型

New model of wellbore temperature field during drilling process

准确预测井筒温度分布及其变化规律,对安全高效钻进具有重要意义。针对目前温度场模型求解过程复杂且计算量相对较大的问题,以传热学基本原理为基础,充分考虑钻井过程中岩屑进入环空后对流体热学性能的影响,将井壁至原始地温位置之间的地层等效为一传热体,建立了循环钻进过程中井筒温度场的计算新模型。为验证新模型的合理性,利用2口实测井的温度数据进行了对比验证,新模型模拟结果与实测温度数据吻合较好。循环钻进时,环空井底温度的模型计算值与实测值之间的最大误差不超过7.3%,精度满足工程需要。该模型可为井筒温度场的准确计算提供理论指导。

Accurate prediction of wellbore temperature distribution and its variation is of great significance to safe and efficient drilling.In view of the complexity and the relatively large calculation amount of present temperature field model,considering the variation of thermal performance of the fluid when cuttings come into the annulus and taking the formation between the borehole and the position where the temperature is the original geothermal as a heat transfer body,the model of wellbore temperature field during drilling process is established on the basis of the basic principle of heat transfer.In order to verify the rationality of the model,the temperature data of the two wells are compared and verified.The simulation results are in good agreement with the measured temperature data.The maximum error between the calculated value of the annular bottomhole temperature and the measured value does not exceed 7.3(,and the accuracy satisfies the engineering requirement.The model can provide theoretical guidance for the accurate calculation of wellbore temperature field.