Estudo da embebição espontanea usando o conceito de difusão capilar com auxilio de tomografia computadorizada

AUTOR(ES)
DATA DE PUBLICAÇÃO

1992

RESUMO

In some kinds of reservoirs a great amount of oil is recovered from a spontaneous imbibition process of the injected or natural aquifer water. This process may be stlldied with the ca.ppiIary diffusion model, and it is usual to assume a constant diffusion coeficient. The purpose of this work was to study the imbibition process with the cappiIary model, but assuming that the diffusion coeficient depends on the water saturation. The influence of gravitational effects and of the form of the function that relates the coefficient to the saturation was verified using numerical and analytical solutions. Two methods of evaluating the diffusion coefficient were discussed iD their the oretical and experimental aspects. A Dew concept of "gravitational diffusion" is taken from soiJ physics. The application of this concept in the numerical analysis of diffusion processes suggests that it could be applied to petrophysical analysis. This approach opens up new ways of studying porous media flow. X-ray computer tomography (CT) was used in order to obtain experimentally the phases saturation distributions in air-water imbibition experiments. These distributions are processed to compute the cappilary díffusion coefficient. The principIes of tomography are presented and some practical aspects related to experimental procedures of cappilary diffusion are discussed.

ASSUNTO(S)

petroleo - geologia reservatorios

ACESSO AO ARTIGO

Documentos Relacionados