Experimental study on imbibition displacement mechanisms of two-phase fluid using micromodel: Fracture network, distribution of pore size, and matrix construction

Abstract

In this study, the effect of different parameters on the fluid transport in a fractured micromodel has been investigated. All experiments in this study have been conducted in a glass micromodel. Since the state of wetting is important in the micromodel, the wetting experiments have been conducted to determine the state of wetting in the micromodel. The used micromodel was wet by water and non-wet regarding normal decane. The fracture network, distribution of pore size, matrix construction, and injection rate are the most important parameters affecting the process. Therefore, the influence of these parameters was studied using five different patterns (A to E). The obtained results from pattern A showed that increasing water injection the flow rate results in both higher rate of imbibition and higher ultimate recovery. Pattern B, which was characterized with higher porosity and permeability, was employed to study the effect of matrix pore size distribution on the imbibition process. Compared to pattern A, a higher normal decane production was observed in this pattern. Patterns C and D were designed to understand the impact of lateral fractures on the displacement process. Higher ultimate recoveries were obtained in these patterns. A system of matrix-fracture was designed (pattern E) to evaluate water injection performance in a multi-block system. Injection of water with the flow rate of 0.01 cc/min could produce 15% of the oil available in the system. While in the test with the flow rate of 0.1 cc/min, a normal decane recovery of 0.28 was achieved.

Pore-scale study of counter-current imbibition in strongly water-wet fractured porous media using lattice Boltzmann method

“…Later, they further verified such a finding by micromodel experiments with the aid of pore-scale imaging techniques. Jafari et al 22 studied the effect of fracture network topology, pore sizes distribution and structure of matrix and injection rate on the spontaneous imbibition using a glass micromodel.…”

Homogenized model with memory for two-phase compressible flow in double-porosity media

“…This is why, the physics of two-phase flow in fracturedporous media continue to be studied mainly experimentally, or numerically. Among the recent experiments, it is important to cite the studies based on transparent glass micromodels: 17 , 18 , 25 , and on real rock samples scanned by nuclear magnetic resonance technique: 20 . The numerical modeling of the first kind is based on Darcy's scale model: 14 , 15 , 23 , 25 , 26 , in which the main problem is focused on matching two-dimensional schemes for fractures with three-dimensional schemes for blocks.…”

“…However, the results remain contradictory regarding the dependence of the ultimate recovery on the injection rate. In 16 , 18 , 24 , 25 the ultimate recovery decreases with the injection rate, whilst in 17 However, the development of such a theory is possible. More exactly, it is possible to develop the completely averaged model of such systems, in which nonlocality and nonlinearity are superimposed.…”

Macroscopic Model of Two-Phase Compressible Flow in Double Porosity Media

“…In this regard, the physics of two-phase flows in fractured-porous media continues to be studied not only by averaging methods, but also by other methods. Pore-level experimental studies are carried out on glass micromodels [14,15,23] with visual observation of the process. Experiments at the Darcy level are conducted in opaque rock samples scanned by nuclear magnetic resonance [16].…”

“…In all these studies, similar results were obtained regarding the role of capillary imbibition on oil recovery: the greater the capillary pressure, the more intensive the imbibition and the higher amount of oil is produced from the blocks. However, there are conflicting results regarding the effect of the displacement rate on oil recovery: in [13,15,21,22], the recovery decreases with increasing injection rate, while in [14,16] it increases. This indicates that the general physical theory of two-phase flows in a medium with strong inhomogeneities remains an open question.…”