CFD Study of Cuttings Transport in Vertical Rotation Drill Pipe for Multi Muds

The ability of drilling fluids to clean the borehole is considered an important factor in choosing drilling mud. Which is affected by many parameters such as mud type, cutting size, cutting concentration in the mud, drill pipe rotation speed, and mud inlet velocity. The present research investigated the influence of drilling fluid that flow into the rotary pipe and coming out of the annulus with the influence of the above mentioned parameters on the cutting transport ratio (CTR). A Computational Fluid Dynamics (CFD) software ANSYS FLUENT 18.2 has been utilized to simulate a model of 3-D two phase (solid-liquid) turbulent flow, steady-state, with stander k-ϵ in a vertical wellbore. The momentum and continuity equations, which are the governing equations, are numerically resolved using CFD with fluent soft package. The results are presented as follows: streamline , contours. The results show that with a decrease in each of the cutting diameter, cutting concentration in the mud, and cutting density, the CTR by mud will increase. Moreover, as the drill pipe rotation speed increases and the mud inlet speed increases, the cutting transport ratio will increase.