Metodologia para análise de rochas por meio digital utilizando microct e simulações de fluxo de fluidos

Abstract

X-ray microtomography (microCT) can be applied for 3D visualization of the internal structure and quantitative analysis of a pore network in a nondestructive manner. With the growth of computer simulation combined with the use of digital images, the use of digital rock analysis has become increasingly common. The simulation of the fluid flow through a porous media is of great relevance in applications related to the exploration of oil and gas reserves. The use of a representative volume of the element (REV) is necessary due to the total reconstructed image volume demonstrates a high computational cost and, in some cases, run the simulation is unfeasible. However, when investigating different types of rocks, some key issues are addressed related to the use of REV, such as the reliability of the representative volume about the total volume of the sample. Quantitative and qualitative results, such as porosity, anisotropy, and permeability vary with the region selected for REV, as well as the configuration of the pores connected depending on the chosen region. In the methodology, we used the Navier-Stokes equations to simulate the fluid flow and applied this convergent analysis in different regions along with the samples of Indiana Limestone, Coquina, and Sandstone. With the results, were possible to characterize and evaluate the rock samples using the information obtained with this methodology, which can be applied in reservoirs characterization.