permeability-saturation-capillary pressure Kr-S-Pc relationships. The significance of the . This sand is available in the market and is known as “Kerbala's sand”. For instance, the relative permeability profiles and capillary pressure profiles are generated based on Brooks- Corey correlation using MATLAB. ECLIPSE is. The results show that the relative permeability (k r) is a power function of the relative permeability law to achieve a different relationship (k r ∼s). On the other hand, the capillary pressure (p c), which is defined as a pressure .. simultaneously assessing social readiness and market support for changes to.
The drainage and imbibition terminology for saturation changes breaks down when applied to reservoirs with nonuniform wettability. Rather than using drainage and imbibition to refer to the decreasing and increasing saturation of the wetting phase, some engineers define these terms to mean decreasing and increasing water saturation, even if water is not the wetting phase for all surfaces.Transactional Marketing Vs. Relationship Marketing
Twenty-five of the reservoirs were carbonate, and the others were silicic 28 sandstone, 1 conglomerate, and 1 chert. At the time of publication init was surprising to readers that two-thirds of the reservoirs were oil-wet.
Previously, reservoirs were believed to be mostly water-wet.
Determining the Effect of Neglecting Capillary Pressure on Fractional Flow by Numerical Analysis
Table 1 Drainage and imbibition for a strongly wet system An example of capillary pressure relationships during drainage and imbibition for an unconsolidated dolomite powder is shown in Fig. The imbibition curve remains above zero capillary pressure, similar to the typical form of Fig. After Morrow et al. Such heterogeneities give rise to "bumps" in a capillary pressure relationship. An example of these bumps is shown in Fig. The permeabilities of the two layers differ by a factor of 4, and the threshold pressures differ by a factor of 2 per the inverse-square-root proportionality to permeability that is suggested by Eq.
Capillary pressure -
The threshold pressure for the higher-permeability layer is 1 psi. The residual oil saturation is 0. All layers have the same thickness. The consequence is a bump in the capillary pressure relationship at oil saturation equal to approximately 0. Heterogeneities other than laminations can cause bumps. Any porous material that is a composite of two types of pore structure should demonstrate bumps. Similar bumps are often seen for actual rock, as demonstrated with the mercury capillary pressure data in Fig.
Wettability As reported by Bethel and Calhoun,  wettability affects the position of capillary pressure curves, as shown in Fig. The contact angles in the legend of Fig. The wettability moves from strongly water-wet at the top of the legend to strongly oil-wet at the bottom. With increasing oil wetness, the capillary pressure shifts upward, reflecting the increased pressure needed to push water into the pore spaces of the specimen. The legend gives contact angles measured through the water phase in degrees.
Jerauld and Rathmell  report the imbibition and secondary-drainage data of Fig. As is typical of mixed-wet samples, the water saturation increases rapidly during imbibition for decreasing capillary pressure in the vicinity of zero.
- Comparison Between Capillary Pressure and Relative Permeability
- Relative permeability and capillary pressure
- Capillary pressure
Similarly, water saturation decreases rapidly during the secondary-drainage cycle for increasing capillary pressure just above zero. Hence, the capillary pressure has no visible effect towards the core length. Keywords Fractional flow; Capillary pressure gradient; Relative permeability; Two-phase flow Introduction Reservoirs are rarely homogenous.
The effect of neglecting the capillary pressure in fractional flow approach faced more problems in heterogeneous properties, multiple spatial dimension and temporal changes. Although advection flow is highly dominated, diffusion flow existed in some parts of the reservoir.
Capillary pressure is a function of pore size distribution factor which is affected by porosity and permeability. In addition, the capillary pressure gradient in the fractional flow equation is influenced by several parameters such as porosity, permeability, length and injection rate.
The objective of this project is to study the effect of the above-mentioned parameters on the induced errors by zero capillary pressure assumption in fractional flow. The scope of this study involved the fundamentals of reservoir engineering such as multiphase flow, immiscible displacement and horizontal displacement. In addition, the project focused on mathematical simulation which is by using one-dimensional black simulation.
The result is dependent on the usage of literature correlations and equations. Most of the theoretical and empirical correlations are in accordance to limitations and assumptions.
ECLIPSE is used to generate the saturation profile through one-dimensional black oil simulation in core flooding by gas -water drainage process. The Design of Experiment DOE was used to establish the factorial design based on different parameters in multiple levels and the responses were analyzed.
Conceptual Framework Fractional flow concept A well-established theory developed by Buckley-Leverett known as the Frontal Displacement theory is able to determine the displacement of immiscible fluid in porous medium [ 1 ]. Morel-Seytoux states that the flow of air and water in unsaturated soils can be viewed as a multi-phase system and proposed that this concept can aid the Petroleum Engineers [ 2 ].
However, the viscosity of the fluid should be considered. Therefore, the concept proposed by Morel-Seytoux might not be applicable for oil - water system due to the high difference in viscosity ratio. The Darcy Equation is the standard mathematics tools for the petroleum engineers to determine the fluid flow. Assuming that an incompressible fluid is flowing linearly in a horizontal core sample with cross sectional area A and length Lthen the fluid flow equation is expressed as Darcy Equation 2 [ 3 ].
Ahmed suggested that Equations 3 and 4 below indicates that when gas is displacing the water, the increment in fg at any point will result in corresponding decrease in fw [ 3 ]. Based on Equation 6fractional flow equation is a function of saturation. This phenomenon is physically impossible and occurs due to the negligence of capillary pressure. Computed water saturation profile . Figure 2 shows that a displacement front was proposed to rectify the discontinuous saturation profile by balancing the area ahead of the front and below the curve.
This solution provides an ideal piston-like displacement [ 1 ]. Final water saturation profile . Relative permeability and capillary pressure profile Fractional flow is a function of mobility ratio which requires the relative permeability profile.