空气反循环钻井井底流场模拟实验器的研制

井底流场是空气反循环钻井能否高效携岩和有效形成反循环的核心流场,而井底流场模拟实验器是开展相应研究的关键设施和必要手段。基于反循环井底流场形成特点,设计了空气反循环钻井井底流场模拟实验器装置,并对主要零部件的设计过程进行了详细分析。井底流场模拟实验器可模拟不同切削具底出刃对应的中心孔压力变化;内喷孔与底喷孔不同组合情况下孔底流量分配;及不同类型内管倾角变化对中心孔压力影响的实验研究。进而也可考察不同结构参数变化对井底流场的影响,为空气反循环钻井井底工具的结构优化设计提供重要的理论和试验依据。 

Development of bottom hole flow simulation experimental apparatus for air reverse circulation drilling

Bottom hole flow is the core flow field because it effects the efficiency of carrying cuttings of reverse circulation drilling.Bottom hole flow simulation experimental apparatus is the critical facilities and necessary means to carry out the corresponding research.Based on the formation characteristics of reverse circulation bottom hole flow field,the bottom hole flow simulation experimental apparatus of air reverse circulation drilling was de-signed,and the design process of main components was analyzed in detail.The pressure change with different cut-ting element,the bottom flow distribution in the condition of different combinations of the inner nozzles and the bottom nozzles and the effects between the different types inner tube inclination and the center hole pressure could be measured with experimental apparatus.Furthermore,different structural parameters influencing the bottom hole flow field were examined,and the results provided important theoretical and experimental basis for the structural optimization design of bottom hole tools for air reverse circulation drilling.