방향성 소구경 굴착의 입자 이송특성에 관한 연구

• Published in: Han-guk haeyang gonghak hoeji (Online) Vol. 26; no. 2; pp. 20 - 25
• Main Authors: 한상목(Sang-Mok Han), 김정환(Jeong-Hwan Kim), 황영규(Young-Kyu Hwang), 우남섭(Nam-Sub Woo), 김영주(Young-Ju Kim)
• Format: Journal Article
• Language: Korean
• Published: 한국해양공학회 2012
• Subjects: 해양공학; Slim hole drilling 소구경굴착; Directional drilling 방향성굴착; Solid-liquid two phase flow 고-액 2상 유동; Drilling fluid 굴착유체; Cuttings 굴착암편; 2
• ISSN: 1225-0767; 2287-6715

During drilling, the precipitation velocity of cuttings within an annulus depends on the density and configuration of the cuttings, and on the density, viscosity, and rheological characteristics of the drilling fluid. In directional drilling in particular, it is difficult to adjust and control the cuttings. In contrast to vertical drilling, it is very important to evaluate the flow characteristics of a drilling flow field. However, research on the transfer features of cuttings is inadequate. In this study, in order to identify transfer features of cuttings, an experiment was performed under wide-ranging conditions by constructing a slim hole annulus ($44mm{\times}30mm$) device. In this experiment, the particle volume fraction were influenced by particle size, particle concentration within the flow, pipe rotation, flow volume, and inclination of the annulus. In addition, a mathematical formula for volumetric concentration was deduced and compared to the test results and behavior of cuttings under the other drilling condition was made to be predicted. Therefore, this study can provide meaningful data for vertical and horizontal drilling, and for directional drilling.