流体机械2012，Vol.40Issue(1)：46-49,53,5.DOI:10.3969/j.issn.1005-0329.2012.01.011
定向喷嘴布置对PDC钻头井底流场影响研究
Directional Nozzle Layout of PDC Bit Bottom-hole Flow Field Impact Study
摘要
Abstract
The directional nozzle arrangement in PDC bit has strongly affected to flow field at the bottom hole, especially when there is a possibility to change the PDC bit hydraulic performance. Therefore, the study on directional nozzle arrangement has the vital significance. The various nozzles layout method was analyzed and numerical simulation of its PDC bits bottom flow field was carried on. The results showed that;in the jet impact area of incompletely symmetrical layout, the jet blowing from the nozzle to the bottom hole, and before reaching the bottom hole, the jet is located in the attenuation zone. This plays an important impact for the cleaning bit and transport drill cuttings out of the well; In the vortex, when jet angle is large and distance from drill center to the nozzle is far, the jet is merely used for cleaning and carrying drill cuttings in the vicinity of bottom hole, when the jet angle is small, the distance from the drill center to the nozzle is relatively close, the jet is merely used for cleaning and carrying drill cuttings on the center of bottom hole; In the blade boundary layer on the nozzle due to surrounding effect, in the surface close to the blade, due to the surround nozzles, the cutting surface low velocity zone is obviously reduced led to shear stress increases, creating favorable conditions in preventing and cleaning drilling balls on PDC bit. The final outcome is increase the mechanical drilling efficiency.关键词
PDC钻头/喷嘴布置/数值模拟/流场Key words
PDC bit/directional nozzle layout/numerical simulation/flow field分类
能源科技引用本文复制引用
黄英勇,李根生,田守嶒,付加胜..定向喷嘴布置对PDC钻头井底流场影响研究[J].流体机械,2012,40(1):46-49,53,5.基金项目
国家重点基础研究发展计划("973计划")项目(2010CB226700) （"973计划"）
国家科技重大专项课题资助项目(2011ZX05009-005) （2011ZX05009-005）
