The Analysis Of Laboratory Fluid/Flow Displacement Data To Obtain Relative Permeability Curves

Abstract

The approaches to analysing unsteady state displacement experiments in order to determine relative permeability curves are reviewed. A new version of the Welge technique, which incorporates, explicit functional forms for relative permeability is developed. The sensitivity of the production nd pressure history to the shape of the relative permeability curve is analysed The influence of capillary pressure is then predicted by comparing results from the Welge technique and from the numerical simulator. INTRODIXTION Relative permeability measurement methods may be broadly classified into two types: steady state and unsteady state. For the steady state method, the phases are injected at a fixed volumetric ratio until pressure and flow equilibrium have been established. The pressure drops across the core of each phase (,IP8) and the flow rates of each phase (Qa) are then used to calculate the relativ 25-1 permeabilities (kra) bY means of the Darcy equation Qa ua L where lAa is the viscosity. k is the absolute permeability, A-is the cross sectional area of the sample and L is the length of the sample.A saturation of the sample is also required, this is typically determined by weight. The unsteady state method is based on interpreting an immiscible displacement process. This interpretation is based on orie of the two approaches: application of the Welge Theory (see Johnson, Bossler and Naumann or Jones and Roszelle or numerical simulation (see Sigmund and McCaf'fery3). The Welge approach requires the determination of the derivative of fractional flow with saturation. These derivatives are usually found either

An artificial-intelligence-based petrophysical property predictor for compositional volatile oil reservoir using three-phase production data

“…Numerous tests have been performed using techniques created around this concept. Such studies include the following: Goodfield et al, 2001;Helset et al, 1998;Islam and Bentsen, 1986;Johnson et al, 1959;Jones and Roszelle, 1978;Kalbus and Christiansen, 1995;Marle, 1981;Ruth et al, 1988;Sigmund and McCaffery, 1979;Siddiqui et al, 1998;Toth et al, 2001, and Welge, 1952. Johnson et al (1959 developed a displacement test to estimate the relative permeability of reservoir formation.…”

“…Marle (1981) proposed an unsteady-state measurement method. Ruth et al (1988) improved the Welge method (1952) by incorporating explicit relative permeability function forms and did sensitivity analysis. Toth et al (2001) developed an unsteady-state method for two-phase fluid injection settings during relative permeability measurements.…”

Proxy models for evaluation of permeability, three-phase relative permeability, and capillary pressure curves from rate-transient data

“…2 Some experiments using the unsteady-state method have been developed. 3–14 However, the unsteady-state method is embedded with one-dimensional (1D) flow and homogeneous porous media assumptions, which could incur error, as pointed out by Johnson et al 3 Some other shortcomings were pointed out by Heaviside and Black 15 and Crotti and Rosbaco. 16 Besides these well-studied flaws, the most fundamental limitation is the same as the steady-state methods, in that this method requires cores and experimental measurements.…”