Fluid saturation

The relative permeability to phase i, kri(s ), is taken to be a function of fluid saturation si which is the fraction of the pore space occupied by phase i it is supposed that any associated spatial variations are largely taken into account through the permeability. For two-phase flow, fluid saturations are related by... 

If the amount of fluid within a fully saturated permeable medium is known as a function of position, the spatially resolved porosity distribution can be determined. If the medium is saturated with two fluids, and the signal from one can be distinguished, the fluid saturation can be determined. In this section, we will develop a method to determine the amount of a single observed fluid using MRI, and demonstrate the determination of porosity. In Section 4.1.4.3, we will demonstrate the determination of saturation distributions for use in estimating multiphase flow functions. 

Relative permeability and capillary pressure functions, collectively called multiphase flow functions, are required to describe the flow of two or more fluid phases through permeable media. These functions primarily depend on fluid saturation, although they also depend on the direction of saturation change, and in the case of relative permeabilities, the capillary number (or ratio of capillary forces to viscous forces). Dynamic experiments are used to determine these properties [32]. 

An actual vapor compression refrigeration cycle operates at steady state with R-134a as the working fluid. Saturated vapor enters the compressor at 263 K. Superheated vapor enters the condenser at 311K. Saturated liquid leaves the condenser at 301 K. The mass flow rate of refrigerant is 0.1 kg/sec. Determine... 

Simulation results are shown here in terms of zinc metal vented into the ocean by hydrothermal fluid saturated with respect to zinc sulfide, the concentration of which increases exponentially with temperature (capped at 14.5 ppm at 400°C). The specific relation is similar to the one given by Large (1992), and is calibrated to end-member concentrations derived from seafloor observations (Seyfried et al. 2003). Details of the calculations are outlined in Carr et al. (2008). 

The most popular method used is a dynamic method, the saturation method. In this technique, the non-volatile, heavy solid solute is loaded into a saturator, or a battery of two or more saturators connected in series, and remains there as a stationary phase during the experiment. In most cases the saturator is in the form of a packed column. At constant pressure, a steady stream of supercritical fluid (solvent) passes through a preheater, where it reaches the desired system temperature. Then this fluid is continuously fed to the bottom of the saturator, and the solute is stripped from the stationary heavy phase in the column. The supercritical fluid saturated with the solute leaves the saturator at the top. 

Drilling rate The drilling rate also decreases in the hydrate region relative to that in a fluid-saturated sediment, but not significantly different from that of ice... 

Biot M. A. (1956) Theory of propagation of elastic waves in a fluid-saturated porous medium. Low frequency range. Journal of Acoustical Society of America 28, 168-191... 

Soft biological structures exhibit finite strains and nonlinear anisotropic material response. The hydrated tissue can be viewed as a fluid-saturated porous medium or a continuum mixture of incompressible solid (s), mobile incompressible fluid (f), and three (or an arbitrary number) mobile charged species a, (3 = p,m, b). A mixed Electro-Mechano-Chemical-Porous-Media-Transport or EMCPMT theory (previously denoted as the LMPHETS theory) is presented with (a) primary fields (continuous at material interfaces) displacements, Ui and generalized potentials, ifi ( , r/ = /, e, to, b) and (b) secondary fields (discontinuous) pore fluid pressure, pf electrical potential, /7e and species concentration (molarity), ca = dna/dVf or apparent concentration, ca = nca and c = Jnca = dna/dVo. The porosity, n = 1 — J-1(l — no) and no = no(Xi) = dVj/dVo for a fluid-saturated solid. Fixed charge density (FCD) in the solid is defined as cF = dnF/dV , cF = ncF, and cF = cF (Xf = JncF = dnF/d o. 

In this paper a static linear elastic deformation problem for a fluid saturated solid is formulated in which the behavior of the solid matrix is described by a second gradient model. The non-deformed configuration, chosen as a reference configuration, for the considered mixture can not be stress-free indeed the saturating fluid must exhibit internal stresses acting both on the solid constituent and on its sub-bodies. 

The macroscopic drained stiffness tensor Chom(f) and Biot s coefficient B( ) can then be expressed as a function of the average of A over the fluid saturated pore space (I=fourth identity tensor) ... 

Figure 8. Final Fluid Saturations for Foam Displacement of Brine...

The second type of thermodynamic problem is concerned with comparing parallel reactions in pure and impure systems. In the case of calcite dissolution we ask, how will rate change at constant pH and PCO2 owing to the presence or absence of an impurity Equation 14 shows that thermodynamic effects of impurities on the rate of calcite dissolution are accounted for by calculation of the bulk fluid saturation (f ) and the equilibrium activity of H in the adsorption layer (aH+(s)). The following example demonstrates one possibility. 

Girnis A. V., Brey G. P., and Ryabchikov I. D. (1995) Origin of Group lA kimberlites fluid-saturated melting experiments at 45-55 kbar. Earth Planet. Sci. Lett. 134, 283 —296. 

All sediments have some natural porosity and begin expelhng fluids during compaction. They generally remain fluid saturated during prograde metamorphism, and equilibration of major elements can be generally assumed (Carlson, 2002)... 

A fluid is only produced if a given rock volume is already completely hydrated (fluid saturated). If fluid saturation is not realized at the beginning of subduction, a number of fluid-absent reactions will take place. These reactions are of the type... 

A- -Vi = B- -V2 (where A, B are volatile free phases and Vi, V2 are hydrous phases or carbonates), involve hydrates and/or carbonates and change the mineralogy of a rock volume according to the stability fields of the minerals, but do not liberate a fluid. Prograde subduction zone metamorphism (as is true for any type of prograde metamorphism) generally reduces the amount of H2O that can be stored in hydrous minerals with depth. Thus, almost any part of the oceanic crust sooner or later becomes fluid saturated. In an equilibrium situation, the volatile content bound in hydrous phases and carbonates remains constant until fluid saturation occurs. Either continuous or discontinuous reactions may lead to fluid saturation in a rock. The point at which this occurs depends on initial water content, and pressure and temperature, and somewhat counter-intuitively, initial low water contents do not cause early complete dehydration, but delay the onset of fluid production to high pressures. 

Melting of subducted crust can occur under fluid-saturated or huid-absent conditions. The principal hydrous phases involved are phengite, biotite, epidote/zoisite, and amphibole. If melting of the oceanic crust occurs at pressures below 2.5 GPa, the oceanic crust will go through a greenschist and epidote-amphibolite facies stage at low pressures (both stages not discussed above). 

Fluid-saturated melting of basaltic crust begins at temperatures of —650 °C at 1.5 GPa to —750 °C at 3 GPa (Figure 5). It should be noted that... 

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