多股撞击射流流场的数值模拟研究

AN NUMERICAL STUDY ON FLOW FIELDS OF MULTIJETS IMPINGING ON THE BOTTOMHOLE

应用湍流模拟技术中的大涡模拟方法，对井底多股受限撞击射流的流场特性进行数值模拟。通过对模拟结果的分析，给出了井底条件下多股圆喷嘴撞击射流流场结构的精细描述；揭示了不同钻头水力结构条件下流场中“旋滚圈”的存在，进而探讨了井底岩屑随液流流动的运移机理，提出了有关井底清岩理论的新观点。

The LES (large eddy simulation) approach has been applied successfully to simulate the flow characteristics of multijets impinging on the bottomhole.The flow fields of the limited multijets have been minutely described and 'vortexring' in the flow fields with different hydraulic configurations have been first found by analysis of numerical simulation.The mechanism that cuttings were removed and transported by drilling fluids at bottomhole were investigated,and some new viewpoint on bottomhole cleaning were proposed.