Type-Curve Analysis Using the Pressure Integral Method

1989 ◽  
Author(s):  
T.A. Blasingame ◽  
J.L. Johnston ◽  
W.J. Lee
Keyword(s):  
Integral Method ◽  
Curve Analysis ◽  
Type Curve

Unified Decline Type-Curve Analysis for Natural Gas Wells in Boundary-Dominated Flow

SPE Journal ◽  
2012 ◽  
Vol 18 (01) ◽  
pp. 97-113 ◽  
Author(s):  
Ayala H Luis F. ◽  
Peng Ye
Keyword(s):  
Natural Gas ◽  
Constant Pressure ◽  
Curve Analysis ◽  
Production Data ◽  
Gas Wells ◽  
Production Potential ◽  
Type Curve ◽  
Type Curves ◽  
Decline Curve Analysis ◽  
Decline Curve

Summary Rate-time decline-curve analysis is the technique most extensively used by engineers in the evaluation of well performance, production forecasting, and prediction of original fluids in place. Results from this analysis have key implications for economic decisions surrounding asset acquisition and investment planning in hydrocarbon production. State-of-the-art natural gas decline-curve analysis heavily relies on the use of liquid (oil) type curves combined with the concepts of pseudopressure and pseudotime and/or empirical curve fitting of rate-time production data using the Arps hyperbolic decline model. In this study, we present the analytical decline equation that models production from gas wells producing at constant pressure under boundary-dominated flow (BDF) which neither employs empirical concepts from Arps decline models nor necessitates explicit calculations of pseudofunctions. New-generation analytical decline equations for BDF are presented for gas wells producing at (1) full production potential under true wide-open decline and (2) partial production potential under less than wide-open decline. The proposed analytical model enables the generation of type-curves for the analysis of natural gas reservoirs producing at constant pressure and under BDF for both full and partial production potential. A universal, single-line gas type curve is shown to be straightforwardly derived for any gas well producing at its full potential under radial BDF. The resulting type curves can be used to forecast boundary-dominated performance and predict original gas in place without (1) iterative procedures, (2) prior knowledge of reservoir storage properties or geological data, and (3) pseudopressure or pseudotime transformations of production data obtained in the field.

Type-Curve Analysis Using Homotopy Analytical Technique for Evaluation of Reservoir Rock Properties

2018 ◽  
Author(s):  
Ibrahim Ayuba ◽  
M. B. Adamu ◽  
Ibrahim Salahudeen ◽  
A. U. Faruk ◽  
H. Ismail
Keyword(s):  
Curve Analysis ◽  
Reservoir Rock ◽  
Rock Properties ◽  
Type Curve ◽  
Analytical Technique

Decline Curve Analysis Using Type Curves for Two-Porosity Systems

1981 ◽  
Vol 21 (03) ◽  
pp. 354-362 ◽  
Author(s):  
Giovanni Da Prat ◽  
Heber Cinco-Ley ◽  
Henry Ramey
Keyword(s):  
Fluid Flow ◽  
Flow Rate ◽  
Skin Effect ◽  
Curve Analysis ◽  
Fractured Reservoir ◽  
Type Curve ◽  
Decline Curve Analysis ◽  
Decline Curve ◽  
Wellbore Storage ◽  
Naturally Fractured

Abstract Constant producing pressure solutions that define declining production rates with time for a naturally fractured reservoir are presented. The solutions for the dimensionless flow rate are based on a model presented by Warren and Root. The model was extended to include constant producing pressure in both infinite and finite systems. The results obtained for a finite no-flow outer boundary are new and surprising. It was found that the flow rate shows a rapid decline initially, becomes nearly constant for a period, and then a final decline in rat,- takes place.A striking result of the present study is that ignoring the presence of a constant flow rate period in a type-curve match can lead to erroneous estimates of the dimensionless outer radius of a reservoir. An example is presented to illustrate the method of type-curve matching for a naturally fractured system. Introduction Naturally fractured reservoirs consist of heterogeneous porous media where the openings (fissures and fractures) vary considerably in size. Fractures and openings of large size form vugs and interconnected channel, whereas the tine cracks form block systems which are the main body of the reservoir (Fig. 1). The porous blocks store most of the fluid in the reservoir and are often of low permeability, whereas the fractures have a low storage capacity and high permeability. Most of the fluid flow will occur through the fissures with the blocks acting as fluid sources. Even though the volumetric average permeability in a naturally fractured system is low, such systems often exhibit an effective permeability that is higher than the block matrix permeability, and behave differently from ordinary homogeneous media. These systems have been studied extensively in the petroleum literature. One of the first such studies was published by Pirson in 1953. In 1959, Pollard presented one of the first pressure transient models available for interpretation of well test data from two-porosity systems. The most complete analysis of transient flow in two-porosity systems was presented in 1960 by Barenblatt and Zheltov. The Warren and Root study in 1963 is considered the forerunner of modern interpretation of two-porosity systems. Their paper has been the subject of study by many authors. The behavior of fractured systems has long been a topic of controversy Many authors have indicated that the graphical technique proposed by Pollard in 1959 is susceptible to error caused by approximations in the mathematical model. Nevertheless, the Pollard method still is used. The most complete study of two-porosity systems appears to be the Mavor and Cinco-Ley study in 1979. This study considers wellbore storage and skin effect, and also considers production, both at constant rate and at constant pressure. However, little information is presented concerning the effect of the size of the system on pressure buildup behavior.Although decline curve analysis is widely used, methods specific to two-porosity fractured systems do not appear to be available. It is the objective of this paper to produce and study decline curve analysis for a naturally fractured reservoir. The Warren and Root model was chosen as the basis for this work. Partial Differential Equations The basic partial differential equations for fluid flow in a two-porosity system were presented by Warren and Root in 1963. The model was extended by Mavor and Cinco-Ley to include wellbore storage and skin effect. SPEJ P. 354^

Sign in / Sign up

Export Citation Format

Share Document