Transient cutting transport model for horizontal wells with a slim hole

Abstract Compared with conventional drilling methods, the method of horizontal wells a slim hole (HW‐SH) has advantages, such as high productivity, environment‐friendliness, and low costs. However, during process, narrow annulus may become blocked, which lead to an increase in pressure if wellbore is not clean. This often leads serious accidents, sticking leaking formations. Many models have been used study cutting transport law annulus, but influence drill‐pipe rotation on ignored weakened these models. None existing can effectively simulate entire well section. Therefore, using predict HW‐SH will cause significant errors. In this study, authors first establish pipeline model same size on‐site computational fluid dynamics (CFD). Subsequently, one‐dimensional (1D) two‐layer that uses three correction factors express loss developed. Finally, parameters 1D are calibrated CFD simulation results accurately behavior annular loss. From calculation quality, section‐cutting concentration, drop, it was observed two algorithms proposed degree coincidence, thereby confirming reliability model. The provides close three‐dimensional (3D) accuracy at much shorter central processing unit time than 3D addition, developed verified indoor two‐phase flow experiment conducted University Tulsa, without considering drill pipe.