Authors: Xuefeng Liu Jianmeng Sun Haitao Wang
Publish Date: 2009/06/26
Volume: 6, Issue: 2, Pages: 105-112
Abstract
A 3D digital core describes the pore space microstructure of rocks An Xray micro CT scan is the most accurate and direct but costly method to obtain a 3D digital core In this study we propose a hybrid method which combines sedimentation simulation and simulated annealing SA method to generate 3D digital cores based on 2D images of rocks The method starts with the sedimentation simulation to build a 3D digital core which is the initial configuration for the SA method We update the initial digital core using the SA method to match the autocorrelation function of the 2D rock image and eventually build the final 3D digital core Compared with the typical SA method the hybrid method has significantly reduced the computation time Local porosity theory is applied to quantitatively compare the reconstructed 3D digital cores with the Xray micro CT 3D images The results indicate that the 3D digital cores reconstructed by the hybrid method have homogeneity and geometric connectivity similar to those of the Xray micro CT image The formation factors and permeabilities of the reconstructed 3D digital cores are estimated using the finite element method FEM and lattice Boltzmann method LBM respectively The simulated results are in good agreement with the experimental measurements Comparison of the simulation results suggests that the digital cores reconstructed by the hybrid method more closely reflect the true transport properties than the typical SA method alone
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