in this paper, the effect of flow rate on relative permeability curves was investigated in iranian carbonate rocks. core samples were prepared from outcrop of asmari formation. the dynamic displacement experiments were performed at 2.55, 3.55, 4.55 and 5.55 cc/hr during waterflooding and oilflooding. relative permeabilities have been calculated with the jones and roszelle method and then the fl...

where Pn and Pw are the average pressures of nonwetting and wetting phases, respectively; Pc is capillary pressure, Capillary pressure plays a central role in the description of water and S is the wetting phase saturation. A schematic depicflow in unsaturated soils. While capillarity is ubiquitous in unsaturated tion of Pc vs. S curves is given in Fig. 1. analyses, the theoretical basis and pra...

The capillary pressure–saturation relationship, Pc(Sw), is an essential element in modeling two-phase flow in porous media (PM). In most practical cases of interest, this relationship, for a given PM, is obtained experimentally, due to the irregular shape of the void space. We present the Pc(Sw) curve obtained by basic considerations, albeit for a particular class of regular PM. We analyze the ...

Citation Cueto-Felgueroso, L., and R. Juanes. " A phase field model of unsaturated flow. Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. The MIT Faculty has made this article openly available. Please share how this access benefits you. Your story matters. [1] We present a phase fie...

There is strong evidence in the literature that traditional equations describing two-phase flow processes in porous media may be inadequate under non-equilibrium or dynamic conditions. There exist theories that propose that the capillary pressure depends not only on saturation but also on the time rate of change of saturation. In this work, the significance of dynamic effects in the capillary p...

BACKGROUND Blood flow limitation to exercising muscles engages the muscle reflex during exercise, evoking an increase in heart rate (HR), blood pressure (BP), and muscle sympathetic nerve activity (MSNA). METHODS AND RESULTS In the current study, we examined forearm flow and autonomic responses to ischemic handgrip in young and older subjects. We studied 6 younger subjects (mean age 23.5+/-2....

Venoarterial extracorporeal membrane oxygenation (VA-ECMO) is indicated in reversible life-threatening circulatory failure with or without respiratory failure. Arterial desaturation in the upper body is frequently seen in patients with peripheral arterial cannulation and severe respiratory failure. The importance of venous cannula positioning was explored in a computer simulation model and a cl...

The knowledge of the area of interfaces between phases is important to understand and quantify many flow and transport processes in porous media. In this work, we apply the interfacial tracer technique to study the dependence of fluid-fluid interfacial area on saturation and wettability. The interfacial area between the wetting and the nonwetting phases (brine and decane) in unconsolidated poro...

We investigate a two-phase porous media flow model, in which dynamic effects are taken into account in phase pressure difference. We consider a one-dimensional heterogeneous case, with two adjacent homogeneous blocks separated by an interface. The absolute permeability is assumed constant, but different in each block. This may lead to the entrapment of the nonwetting phase (say, oil) when flowi...

BACKGROUND Fetal hypoxia has been implicated in the abnormal brain development seen in newborns with congenital heart disease (CHD). New magnetic resonance imaging technology now offers the potential to investigate the relationship between fetal hemodynamics and brain dysmaturation. METHODS AND RESULTS We measured fetal brain size, oxygen saturation, and blood flow in the major vessels of the...