空气反循环钻头设计与数值分析

空气反循环钻头是针对反循环空气钻井技术而开发的一种新型钻头。在常规三牙轮钻头的基础上,应用引射原理对反循环钻头进行结构设计。应用Fluent流体分析软件对2种反循环喷射钻头模型的周围及内部流场进行数值模拟。研究结果表明:在气体流量为50m3/min的条件下,2种不同腔体结构的反循环钻头可以清洗井底岩屑,并使岩屑顺利上返至地表;含有侧水眼的反循环钻头更有利于岩屑快速上返。为设计不同结构参数的反循环钻头提供理论依据。

Design and Numerical Analysis of Air Reverse Circulation Bits

The air reverse circulation drill bit is a new bit specifically developed for reverse circula- tion air drilling technology. By using injection principle, structural design of reverse circulation bit on the basis of the conventional tri cone bit is discussed in this paper, and numerical simulations of external and internal flow fields of two different kinds of reverse circulation jet bit models are per- formed by utilizing Fluent fluid analysis software. The analysis results show that under the condi- tions that the air flow is,the two different cavity structures of the reverse circulation hits are e- nough to clean drilling detritus from the hottom of the well and make the dehris smoothly return to the surface,and the reverse circulation bit designed with side water port can have the drillings to be carried to the surface more quickly. The research results provide a theoretical basis for the design of reverse circulation bits of different structural parameters.