Eventos Anais de eventos
COBEM 2021
26th International Congress of Mechanical Engineering
A First Estimate of the Displacement of Mono Ethylene Glycol in an Oil Pipeline Using Computational Fluid Dynamics (CFD)
Submission Author:
Nathália Roseane de Melo , PE , Brazil
Co-Authors:
Nathália Roseane de Melo, Karen Vieira, Alessandro Antunes, DARLAN KARLO ELISIÁRIO DE CARVALHO, Giselle Silva
Presenter: Nathália Roseane de Melo
doi://10.26678/ABCM.COBEM2021.COB2021-1717
Abstract
The use of chemical products in oil-producing wells, especially in the Brazilian Pre-Salt, is extremely important, as it aims to avoid or mitigate possible flow assurance problems (scale, asphaltenes, hydrates, corrosion, and H2S, for example). The downhole injection of these products, such as scale inhibitors, is carried out through dedicated systems. In these dedicated systems, the occurrence of several problems has been verified, highlighting the U-tube effect and equipment operation failures, which can compromise the efficiency of the diffusion of these products in the production well. Most scale inhibitors use Mono Ethylene Glycol (MEG) as a solvent and to evaluate the effectiveness of fouling inhibitor injection, in the present article we model the fluid flow behavior (velocity, pressure and temperature fields) and the mass fraction displacement of MEG throughout the oil pipeline using Computational Fluid Dynamics tools of the ANSYS FLUENT® commercial software which is based in the cell centered finite volume method. In this initial model, the flow is considered in laminar regime in a 50 m long section of a 11.938 cm diameter oil pipeline. Numerical simulations of the displacement of Mono Ethylene Glycol were performed using product injection volume flow rate ranging from 0.5 to 80 l/h, with a temperature of 80 °C, and oil-water volumetric flow rate of 2139.8 m3/day were simulated. Stationary, non-slip wall boundary conditions were prescribed, with a constant temperature equal to 80 °C. The time-dependent terms were described by the first-order Euler implicit formulation. The PISO algorithm (Pressure Implicit with Splitting of Operators) was used for the pressure-velocity coupling and the estimation of the pressure field on the mesh faces was performed by PRESTO (PREssure STaggering Option). Advective terms in the momentum, energy and the MEG (convection-diffusion) equation were handled by the second order upwind method. In order to improve accuracy and reduce the computational cost, we have used an automatic adaptive mesh procedure. Our preliminary results seem to properly represent the MEG displacement throughout the oil pipeline, but further numerical experiments, e.g., including turbulence, and comparison with data from a real world applications are necessary in order to validate our strategy.
Keywords
Flow Assurance Problems, Displacement of Mono Ethylene Glycol in Oil pipelines, Numerical simulation, Cell Centered Finite Volume
