We consider the imbibition of a liquid droplet into a deformable porous substrate. The liquid in the droplet is imbibed due to capillary suction in an initially dry and undeformed substrate. Deformation of the substrate occurs as the liquid fills the pore space. In our model, a pressure gradient in the liquid across the developing wet substrate region induces a stress gradient in the solid matr...

In this work, we study the lithiation behaviours of both porous silicon (Si) nanoparticles and porous Si nanowires by in situ and ex situ transmission electron microscopy (TEM) and compare them with solid Si nanoparticles and nanowires. The in situ TEM observation reveals that the critical fracture diameter of porous Si particles reaches up to 1.52 μm, which is much larger than the previously r...

Description in terms of physicochemistry and heat and mass transfer of the combustion front propagation in a reactive porous medium remains a challenge to science. The literature about this subject distinguishes two types of problems. The first considers only combustion of the gas phase inside an inert solid porous medium. In the second type, the solid phase reacts with the gas phase; Chemical ...

The migration and entrapment of dense nonaqueous phase liquids (DNAPLs) in aquifer formations is typically believed to be controlled by physical heterogeneities. This belief is based upon the assumption that permeability and capillary properties are determined by the soil texture. Capillarity and relative permeability, however, will also depend on porous medium wettability characteristics. This...

We consider the system of equations governing an incompressible immiscible two-phase flow within an heterogeneous porous medium made of two different rock types. Since the capillary pressure function depends on the rock type, the capillary pressure field might be discontinuous at the interface between the rocks. We introduce multivalued phase pressures to give a sense to the transmission condit...

Abstract A universal capillary pressure model developed from fractal modeling of a porous medium was verified using the experimental data of capillary pressure curves of rock samples from The Geysers geothermal field. The capillary pressure curves were measured using a mercury intrusion technique. The results showed that the universal model could represent the capillary pressure curves of The G...

Two-phase passive heat transport devices such as vapor chambers, loop pipes, and capillary pumped loops utilize porous evaporators for phase change to drive fluid transport. Nucleate boiling can occur within capillary-fed evaporators, especially under high-heat-flux operation, has been visually observed in various experimental studies the literature. However, prior modeling efforts have typical...

We show that when a non-wetting fluid drains a stratified porous medium at sufficiently small capillary numbers Ca, it flows only through the coarsest stratum of the medium; by contrast, above a threshold Ca, the non-wetting fluid is also forced laterally, into part of the adjacent, finer strata. The spatial extent of this partial invasion increases with Ca. We quantitatively understand this be...

∗ In this chapter we uncover through numerical simulation the velocity and pressure fields inside a model porous medium composed of an infinitely extending array of staggered square rods. These microtransport simulations allow for the prediction of macrotransport parameters that are of value to the volume-averaged description of fluid motion in porous media. We focus on computing the macroscopi...

Phase equilibrium calculations for fluids confined inside capillary tubes or porous media are formulated using the isofugacity equations. In this situation, the phase pressures are not equal and it is assumed that they are related by the Laplace equation. With this formulation, existing procedures for phase equilibrium calculations can be readily modified to include capillary effects. In this p...