Eventos Anais de eventos
ENCIT 2016
16th Brazilian Congress of Thermal Sciences and Engineering
INFLUENCE OF GEOMETRIC AND OPERATIONAL PARAMETERS ON HORIZONTAL WELLS CLEANING PROCESS
Submission Author:
Hóliver Zambon Zanete , ES , Brazil
Co-Authors:
Renato Siqueira
Presenter: Renato Siqueira
doi://10.26678/ABCM.ENCIT2016.CIT2016-0110
Abstract
The well drilling process represents a significant part of the total cost of an oil field. The horizontal drilling technique has been widely used in the oil industry because it increases the contact area of the wellbore with the reservoir, improving the extraction efficiency. Despite the benefits, this technique generates some problems. The main problems are the eccentricity of the column, due to the gravitational effects, and sedimentation of the cuttings, which form a solid bed, impairing the transport of the cuttings. Among the parameters that can affect the process are: eccentricity, inner cylinder rotation, axial flow rate and the rheology of the drilling fluid. This study uses Computational Fluid Dynamics (CFD) to evaluate the influence of diameters ratio (k=d_i⁄d_e ), eccentricity (ε), inner cylinder rotation (ω) and Reynolds number (Re) on the flow of a non-Newtonian fluid characterized by Herschel-Bulkley rheologic model. The geometry consists of a 2.5 m long annular space with an inner cylinder diameter (d_i) of 50.8 mm and the outer cylinder diameter varies according to the k value. For this study k value varied from 0.5 to 0.9. The eccentricity ranged from 0 to 0.8. The rotation of the inner cylinder varied from 0 to 400 rpm. The Reynolds number varied 200 to 1000, assuring the condition of laminar flow. The drilling fluid has a specific mass (ρ) of 1000 kg/m3, yield stress (τ0) of 17.81 Pa, consistency index (K) of 0.26 Pa.s and behavior index (n) equal to 0.74. The data show that the inner cylinder rotation has a greater influence on the cleaning process when the diameters ratio is high and eccentricity is present. A multi-regression method was applied in order to determine the influence of all parameters on pressure drop and thus contribute to the definition of a well drilling strategy.
Keywords
CFD, Non-Newtonian fluid, pressure drop, CFD, Non-Newtonian fluid, pressure drop
