液基全过程欠平衡钻井井筒流动模型研究

项目名称： 液基全过程欠平衡钻井井筒流动模型研究

项目编号： No.51204140

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 冶金与矿业学科

项目作者： 魏纳

作者单位： 西南石油大学

项目金额： 25万元

中文摘要： 液基全过程欠平衡钻井能大幅度地提高储层保护效果和单井产量。井筒压力的预测、演变以及控制是实现液基全过程欠平衡钻井的核心，而这一核心的关键是各作业工况条件下的高温、高压复杂多相流动特征参数的数学模型与求解方法。目前，常规多相流动理论还未涉及这类特殊流动的研究。 通过该项目的研究，建立一套高精度耦合地层流动的井筒稳态多相流动与停止循环不同工况条件下的瞬态多相流数学模型与实用计算方法。首先，耦合地层与井筒流动，建立正常钻进稳态气、液、固多相流动数学模型，提出数值解法。其次，根据气液固能量物质交换、损失基本理论建立压力波产生、传递和衰减数学模型。再次，考虑压力波建立气相浮力上升穿越静止非牛顿流体动态数学模型，按照瞬态多相流理论提出数值解法。最后，通过室内大型可视化、现场实验以及数值模拟结果修正数学模型，并得出规律性认识。 该研究成果能丰富和完善液基全过程欠平衡钻井复杂流动理论体系，具有积极意义。

中文关键词： 欠平衡钻井；停止循环；井筒流动；理论模型；瞬态

英文摘要： Liquid-based whole process underbalanced drilling can maximize the protection of pay-zone and improve individual production. The key factor to realize the prediction and control of pressure change for liquid-based whole process underbalanced drilling is the modeling and solution based on the complicated multi-phase flow character parameters under various field operations. At present, regular multi-phase flow theory hasn't involve that type of research by far. The purpose of this research is to build up a system of highly-precise mathematical modeling and practical computation method for transient multiphase flow in circulating and closed wells under various field operations. In the first place, it is to build up mathematical modeling and numerical solution of the steady-state gas-liquid-solid multiphase by coupling the flow between formation and well during drilling. In the second place, based on the form and transfer of the pressure wave, the dynamical mathematical modeling of gas-phase passing though the still non-Newton fluid upward under buoyancy is built up while the numerical solution is provided with the multi-phase fluid theory.Finally, the principle is figured out by the verified mathematical modeling with indoor large-scale visual experiments, field experiments and numerical approach. The research can

英文关键词： UBD；non-circulation；well bore flow；theory model；transient