A pore-scale model is developed to simulate mass transfer between two fluid phases in a porous medium. The approach uses a network description of the pore space and builds on explicit tracking of the fluid-fluid interfaces in the pore network. Mass transfer is computed as local mass fluxes across each interface, and transport equations are solved in the pore network by a characteristic method. ...

Liquid water present in polycrystalline ice at the interstices between ice crystals results in a network of liquid-filled veins and nodes within a solid ice matrix, making ice a low porosity porous media. Here we used nuclear magnetic resonance (NMR) relaxation and time dependent self-diffusion measurements developed for porous media applications to monitor three dimensional changes to the vein...

We report the synthesis and properties of two π-functional heteroaromatic tetracarboxylic acids (isomeric tetrathienoanthracene derivatives 2-TTATA and 3-TTATA) and their self-assembly on highly oriented pyrolytic graphite. Using scanning tunneling microscopy at the liquid-solid interface we show how slight geometric differences between the two isomers (position of sulfur in the molecule) lead ...

In this paper‎, ‎steady flow of a third-grade fluid in a porous half‎ space has been considered‎. ‎This problem is a nonlinear two-point‎ boundary value problem (BVP) on semi-infinite interval‎. ‎The‎ solution for this problem is given by a numerical method based on the feed-forward artificial‎ neural network model using radial basis activation functions trained with an interior point method‎. ...

Transport of emulsions in porous media is relevant to several subsurface applications. Many enhanced oil recovery (EOR) processes lead to emulsion formation and as a result conformance originating in the flow of a dispersed phase may arise. In some EOR processes, emulsion is injected directly as a mobility control agent. Modeling the flow of emulsion in porous media is extremely challenging due...

Flow in discrete networks can be observed in biological, geological, or technical systems. Often, the number of individual segments is very large. Therefore, discrete pressure and flow calculation in each single segment becomes very time consuming, and a continuum model becomes attractive. We apply a global upscaling method based on a spatial average to investigate a porous media network model ...

The behavior of a fluid with competing interaction ranges adsorbed in a controlled pore size disordered matrix is studied by means of grand canonical Monte Carlo simulations in order to analyze the effects of confinement. The disordered matrix model is constructed from a two-dimensional non-additive hard-sphere fluid (which shows close to its demixing critical point large fluctuations in the co...

The polyphenylene network, known as porous graphene, is one of the most important and widely studied two-dimensional materials. As a potential candidate for photocatalysis and photovoltaic energy generation, its application has been limited by the low photocatalytic activity in the visible-light region. State-of-the-art hybrid density functional theory investigations are presented to show that ...

A contemporary procedure to grow artificial tissue is to seed cells onto a porous biomaterial scaffold and culture it within a perfusion bioreactor to facilitate the transport of nutrients to growing cells. Typical models of cell growth for tissue engineering applications make use of spatially homogeneous or spatially continuous equations to model cell growth, flow of culture medium, nutrient t...

Retaining the high energy density of rechargeable lithium ion batteries depends critically on the cycle stability of microstructures in electrode materials. We report the reversible formation of nanoporosity in individual germanium nanowires during lithiation-delithiation cycling by in situ transmission electron microscopy. Upon lithium insertion, the initial crystalline Ge underwent a two-step...