Microfiber filaments are the most common type of microplastic particles polluting the environment and are recognized as a growing threat to groundwater resources and human health. A better understanding of how microfibers move, deform, and settle in the preferential pathways of fluids in subsurface systems would be beneficial in the improvement of current soil remediation procedures, and advance waste disposal management techniques.
We investigate the transport and deformation of microfilaments in a channel with rough boundaries.  An immersed boundary method is used.

Vugs and fractures are common features of carbonate formations. The presence of vugs and fractures in porous media can significantly affect pressure and flow behavior of a fluid.
The Stokes flow in the spheroidal vug was coupled to Darcy’s law in the host matrix using the modified Beavers Joseph boundary condition for the curvy contact between vug and matrix. The pressure field and stream function inside and outside the vug was obtained analytically.

Traditionally in a fractured porous media flow in the fracture is described by Darcy’s law same as the porous matrix. This is however an oversimplification.  Several phenomena cause deviations from Darcy’s law. First, this is a nonzero Reynolds number for flow inside fracture, which determines the non-neglecting nonlinear inertia effects. Secondly, there is the external flux crossing the fracture boundary, which influences both the average mass balance and momentum balance. Third, the real fractures are wavy boundary, which influences flow regimes and their averaged model. The characteristic of flow in a fracture is highly affected by the presence of these phenomena.

It is almost impossible to find a purely homogeneous reservoir, and it is also impossible to have just one scale of fractures in naturally fractured porous reservoirs. The question is: is it possible to use the traditional dual porosity model (i.e. Warren and Roots model) for every fractured reservoir? If not what
are the other choices but Warren and Roots model? For multiscale fractured media what is the effective model?
I have considered the single-phase flow in a multiscale porous medium which represents an infinite set of self-similar double-porosity media. At each scale, the medium consists of a highly permeable network of connected channels and low-permeable blocks. The transition to the macroscale was performed by the means of two-scale homogenization procedure. One step of averaging at each level of hierarchy led to the appearance of the memory terms in the averaged equation. The successive averaging steps led to progressive memory accumulation, so at each step of averaging, the macroscale model changed its type, and even the result of the second step was unknown a priori.

The process of storage of natural gas including significant amount of hydrogen in geological strata consists of the chemical reactivity induced by various classes of bacteria that consume hydrogen for their metabolism and production of biomass. One of the products of such reactions is methane, having higher energy potential than hydrogen. The fundamental technological problem thus consists of intensifying the useful biotic reaction of methanogens and suppressing other hydrogenotrophic reactions caused by other colonies (sulfate-reducing, iron-reducing, acetogen bacteria). The kinetics of all these reactions represent the key element of the theory. This problem is characterized by: the long memory reflecting the non-instantaneous reaction of bacteria to the sharp variation of the environment; the presence of several types of nutrients; the different types of the metabolism as respiration and nutrition; the concurrence between various colonies for nutriments. I have integrated this model in open source DuMux (Stuttgart University) by aid of implementing complementary modules for bacterial population dynamics.

A robust coupling scheme to was developed to couple industrial reservoir simulator tools with a solid mechanics solver.
Flow in a deformable porous medium is decoupled in two sets of equations one representing flow and the other representing deformation problem. The information on pore pressure and displacement of solid structure is communicated between them.
Several scenarios in coupled geomechanical-flow were tested through synthetic and real field cases. The nonlinear mechanical behavior in salt dome was investigated. More importantly, it was shown that the implicit representation of the faulted zones can not be accurate in fault reactivation analysis.