Eventos Anais de eventos
ENCIT 2022
19th Brazilian Congress of Thermal Sciences and Engineering
DISPLACEMENT EFFICIENCY IN WASHOUT ZONES DURING WELL CONSTRUCTION
Submission Author:
Priscilla Varges , RJ
Co-Authors:
Priscilla Varges, Bruno da Silva Fonseca, Lorena Moraes, Elias da Conceição Rodrigues, Monica Naccache, Paulo Roberto de Souza Mendes, Carlos Pessanha Costa Carvalho, Andre Leibsohn Martins, Ingrid SilvaEzechiello da Silva, Pedro J. Tobar Espinoza
Presenter: Monica Naccache
doi://10.26678/ABCM.ENCIT2022.CIT22-0245
Abstract
In the oil industry, drilling, cementing and well completion operations involve the flow, replacement and displacement of fluids. Especially, structured fluids such as cement slurries, drilling fluids, viscous pills and other suspensions and emulsions, which mechanical behavior are typically elasto-viscoplastic, are part of the process. To ensure the success and optimization of such operations, the displacement flows must be accurately predicted. An unsuccessful operation can compromise the well's safety and integrity through undesired inflow into the well, wellbore collapse, inefficient cuttings transport, failure to isolate zones during cementing, among others. A challenging situation occurs when fluids with different densities flow in enlarged zones (washout). This work provides a comprehensive analysis of the displacement process of Newtonian and non-Newtonian fluids through concentric and vertical annular expansions-contractions as a function of rheology, density ratio, flow rate and geometry. The problem was numerically and experimentally analyzed in order to explore the influence of the governing parameters on displacement efficiency. Results showed that hydrodynamic instabilities can appear in a variety of situations. The finite volume method was used to solve the governing mass and momentum conservation equations. To solve the multiphase problem, the volume of fluid method was used. Furthermore, experiments were performed with Carbopol aqueous dispersion been displaced by a glycerin/water mixture varying the dimensions of the geometry and the injection flow rate. A Coriolis flowmeter was used to measure the flow rate and the density of the fluids leaving the test section in order to determine the displacement efficiency. Excellent agreement was observed between numerical and experimental results. It was observed that density ratio plays a major role on displacement efficiency and that the diameter of the eroded zones has a significant impact on the amount of fluid retained inside the cavity. Ultimately, numerical simulations were performed considering geometric dimensions, fluids properties and flow rates typical of oil well cementing operations.
Keywords
Cementing Operation, Washout, Viscoplastic materials, liquid-liquid displacement
