Insight into dust control performance of a reverse circulation drill bit using multiphase flow simulation

Engineering Applications of Computational Fluid Mechanics

Zhiqiang Zhao¹  Xinxin Zhang²  Pinghe Sun²  Zhanghui Wu²  Lubo Tang²  Usman Shabir² 

[1] China Coal Technology and Engineering Group Chongqing Research Institute, Chongqing, People’s Republic of China;Key Laboratory of Ministry of Education on Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring, Central South University, Changsha, People’s Republic of China;

关键词: Reverse circulation;    drill bit;    multiphase flow;    dust control;   

DOI  :  10.1080/19942060.2022.2047110

来源: DOAJ

【 摘 要 】

A feature of reverse circulation pneumatic down-the-hole (DTH) hammer drilling system is its ability to reduce the emission of respirable dust which is known to be harmful to drilling workers and equipment. The enhanced dust control performance of the drilling system requires better understanding and insight into the airflow behavior at the bottom of the borehole. To investigate the transportation and distribution of cuttings under various drilling parameters, and to evaluate the dust control performance, we conducted a series of simulations using computational fluid dynamics (CFD) multiphase modeling. Finite volume analysis was performed on a reverse circulation drill bit with an optimized structure reported in a previous study. The results show that increasing the input airflow rate can directly improve the dust control efficiency. The rising value in terms of cuttings feed concentration, rate of penetration (ROP), particle diameter, and specularity coefficient would decrease the dust control performance. Furthermore, the characteristics of the cutting distribution vary with the operating parameters and demonstrate the multiphase flow pattern in the RC-bit. This work may provide instructive insights into cutting transportation under various drilling parameters commonly considered in the drilling process and promote the development of dust suppression with efficient drilling operations.

【 授权许可】

Unknown