Effect of Rheology on Oil Well Plugging Process

Abstract

The process of oil well plugging is largely used in oil industry. In this process, a cement plug (higher density fluid) is placed over the drilling fluid (lower density) to seal and abandon the well. The success of the operation depends on several aspects, such as the density ratio and the rheology of the fluids. A numerical analysis of the transient flow just after the cement placement in vertical wells is performed, using Fluent software (Ansys Inc.). The conservation equations of mass and momentum are solved using the finite volume technique. The volume of fluid method is used to deal with the multiphase flow - cement / drilling fluid. Both the drilling fluid and the cement paste are viscoplastic liquids, modeled by the Herschel-Bulkley equation. The analysis of flow displacement and interface configuration between these fluids is an important tool for the process optimization. The effects of the density ratio and yield stress on the flow pattern are investigated. It is shown that the flow is highly unstable and that the above mentioned parameters strongly affect the process.

Numerical Study of Oil Well Plugging Process

“…Existem vários estudos numéricos e experimentais que lidam com tamponamento de poços de petróleo. Alguns estão diretamente relacionados (Abdu, Naccache e Mendes [3] ; Kerswell [4] ; Beckett et al [5] ) enquanto que outros (Meiburg et al [12] ) tratam de situações um pouco diferentes embora também apresentem um vínculo considerável com esse tópico.…”

“…Um dos estudos numéricos foi realizado por Abdu, Naccache e Mendes [3] . passo que a razão entre viscosidades variou de 0,5 até 2,0.…”

Estudo Numérico Do Processo De Tamponamento De Poços De Petróleo

“…Um dos estudos numéricos foi realizado por Abdu, Naccache e Mendes [3] . visto que a resistência ao escoamento se torna maior conforme esta tensão aumenta.…”