Well test analysis for multilayered reservoirs with formation crossflow

Well Test Analysis for Multilayered Reservoirs with Formation Crossflow introduces the fundamentals of well test analysis of a multilayered reservoir with formation crossflow. The effects of reservoir parameters on wellbore pressure and flow rate are examined, as is a proper method that has been est...

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Detalles Bibliográficos
Otros Autores: Gao, Chengtai, author (author), Sun, Hedong, author
Formato: Libro electrónico
Idioma:Inglés
Publicado: Cambridge, MA : Elsevier [2017]
Edición:First edition
Materias:
Ver en Biblioteca Universitat Ramon Llull:https://discovery.url.edu/permalink/34CSUC_URL/1im36ta/alma991009630315906719
Tabla de Contenidos:
  • Front Cover
  • Well Test Analysis for Multilayered Reservoirs with Formation Crossflow
  • Copyright
  • Contents
  • About the Author
  • Acknowledgment
  • Introduction
  • Chapter 1: Semipermeable Wall Model of a Multilayer Reservoir with Crossflow
  • 1.1. Introduction
  • 1.2. Semipermeable Wall Model and Fundamental Differential Equations-Oil Reservoir
  • 1.2.1. Semipermeable Wall Model of a Multilayer Oil Reservoir
  • 1.2.2. Fundamental Differential Equations of a Multilayer Oil Reservoir
  • 1.3. Semipermeable Wall Model and Fundamental Differential Equations-Gas Reservoir
  • 1.3.1. Semipermeable Wall Model of a Multilayer Gas Reservoir
  • 1.3.2. Fundamental Differential Equations of a Multilayer Gas Reservoir
  • 1.3.3. Linearization of the Differential Equations of a Multilayer Gas Reservoir
  • 1.4. Crossflow Behavior for Incompressible Flow
  • 1.4.1. Crossflow Caused by Different Boundary Pressures
  • 1.4.2. Crossflow Caused by Permeability Change
  • 1.5. Summary
  • Chapter 2: Single-Phase Fluid Flow in a Two-Layer Reservoir with Significant Crossflow
  • 2.1. Introduction
  • 2.2. Pressure Drawdown and Buildup Behavior When Both Layers Are Completed at a Single Well
  • 2.2.1. Basis Solution for a Single Layer
  • 2.2.2. Assumptions and the Flow Problem of a Layered Reservoir
  • 2.2.3. Numerical Solution
  • 2.2.4. Theory and Analytical Approximations
  • 2.2.5. Summary
  • 2.3. Crossflow Behavior in a Partially Perforated Two-Layer Reservoir
  • 2.3.1. Flow Nature of the Transient Test of a Partially Perforated Well in a Two-Layer Reservoir with Crossflow
  • 2.3.2. Estimation of Reservoir Parameters Using Drawdown Tests
  • 2.3.2.1. A Method for Evaluating Reservoir Parameters
  • 2.3.2.2. The Treatment of the Skin Factor
  • 2.3.3. Summary
  • 2.4. Maximum Effective Hole Mathematical Model and Analytical Solution for a Two-Layer Reservoir.
  • 2.4.1. Maximum Effective Hole-Diameter
  • 2.4.2. Analytical Solution When Both Layers Are Completed with Crossflow
  • 2.4.3. Analytical Solution for a Two-Layer Crossflow Reservoir Perforated Partially with Crossflow
  • 2.4.4. Analytical Solution of a Commingled Reservoir When All Layers Are Completed
  • 2.4.5. A Comparison of a Two-Layer Commingled Reservoir and Crossflow Reservoir
  • 2.4.6. Summary
  • Chapter 3: Pressure Transients and Crossflow Caused by Diffusivities in Multilayer Reservoirs
  • 3.1. Assumption and the Flow Problem
  • 3.2. Approximate Analytic Solutions
  • 3.3. Numerical Solutions for Cases with n=3 and n=5
  • 3.4. Numerical Solutions and Comparison with Theory
  • 3.4.1. Three-Layer Cases
  • 3.4.1.1. Behavior of Wellbore Pressure
  • 3.4.1.2. Behavior of the Flow Rate
  • 3.4.1.3. The kh-Weighted Pressure for the Drawdown Cases
  • 3.4.1.4. Similarity of Area Crossflow Rates
  • 3.4.1.5. Distribution of the Area Crossflow Rates with Time
  • 3.4.1.6. Behavior of Crossflow Velocity
  • 3.4.2. Five-Layer Cases
  • 3.4.2.1. Behavior of Wellbore Pressure
  • 3.4.2.2. Behavior of Area Crossflow Rates
  • 3.5. Analytical Solution of the Three-Layer Reservoir
  • 3.5.1. Assumption and the Flow Problem
  • 3.5.2. Derivation of Solutions for Pressure and Rate
  • 3.6. Summary
  • Chapter 4: Crossflow Behavior and the Determination Reservoir Parameters by Drawdown Tests in Multilayer Reservoirs
  • 4.1. Assumption and Mathematical Expression of the Problem
  • 4.2. The Unsteady Flow Behavior in Drawdown and Buildup Tests When Partial Layers Produce with Crossflow
  • 4.2.1. Behavior of Wellbore Pressure
  • 4.2.2. Behavior of the Area Crossflow Rate
  • 4.2.3. Behavior of Function g(tD)
  • 4.2.4. Behavior of Function g-ln(2dei)
  • 4.3. New Drawdown Test
  • 4.4. Summary.
  • Chapter 5: Determination of Total Productivity by a Constant Wellbore Pressure Flow Test and the Crossflow Behavior in Mu ...
  • 5.1. Assumption and Approximate Theoretical Solution of the Problem
  • 5.2. Numerical Results and Comparison with the Approximation Theory
  • 5.2.1. Flow Rate of Each Layer Changes with Time
  • 5.2.2. kh-Weighted Pressure Changes with Time
  • 5.2.3. Distributions of Pressure Difference Changes with Time
  • 5.2.4. Distributions of Area Crossflow
  • 5.2.5. The Peak Value of qci Changes with Time
  • 5.3. Exact Solution of a Two-Layer Reservoir with Crossflow Under a Constant Pressure Condition
  • 5.3.1. Model Description
  • 5.3.2. Derivation of Solutions for Pressure and Rate
  • 5.3.3. Numerical Inversion of the Laplace Transform and Discussion of Results
  • 5.4. Summary
  • Chapter 6: Determination of Individual Layer Properties by Layer-by-Layer Well Tests in Multilayer Reservoirs with Crossflow
  • 6.1. Assumptions and Mathematical Model
  • 6.2. Approximate Solution of Unsteady Flow in a Three-Layered Reservoir and Its Extension
  • 6.2.1. Approximation Solution for the Short Time Period
  • 6.2.2. Approximation Solution for the Early Transition Period
  • 6.2.3. Approximation Solution for the Long Time Period
  • 6.2.4. Determination of Semipermeability
  • 6.2.4.1. Determine Semipermeability by Steady Wellbore Pressure Differences
  • 6.2.4.2. Determine Semipermeability by the Crosspoint of Two Straight Lines
  • 6.2.5. Buildup Case
  • 6.2.6. Extension to n-Layered Reservoirs
  • 6.3. Discussion of Simulation Results
  • 6.4. Interpretation Theory
  • 6.4.1. The Interpretation of a Drawdown Curve
  • 6.4.2. The Interpretation of Buildup Curves
  • 6.4.3. Extension to n-Layered Reservoirs
  • 6.5. Summary
  • Chapter 7: Determination of Parameters for Individual Layers by Transient Well Tests in Multilayer Reservoirs
  • 7.1. Introduction.
  • 7.2. Approximation Solution of Unsteady-Flow and Crossflow Behavior Caused by Skin Factors
  • 7.2.1. Assumptions and Three Flow Periods
  • 7.2.2. Approximation Solution for the Short Time Period
  • 7.2.3. Approximation Solution for the Long Time Period
  • 7.2.4. Buildup Case
  • 7.2.5. Crossflow Behavior and Comparison of the Simulation Results with the Approximation Theory
  • 7.3. Determination of Parameters for Individual Layers by a Series of Transient Tests
  • 7.3.1. Two-Layer Case, Drawdown Period
  • 7.3.2. Two-Layer Case, Buildup Period
  • 7.3.3. Example1
  • 7.3.4. n-Layer Case
  • 7.3.5. Example2
  • 7.4. Determination of Semipermeabilities by Steady Rates
  • 7.5. Summary
  • Chapter 8: Interpretation Theory for Vertical Interference Testing Across a Low-Permeability Zone
  • 8.1. Introduction
  • 8.2. Model Description
  • 8.3. The Interpretation Theory When q(t) is Known
  • 8.3.1. Case for Known Function f(pw1,pw2)
  • 8.3.2. Case for Unknown Function f(pw1,pw2)
  • 8.3.3. Case for f=αD(pwD1-pwD2)
  • 8.3.4. Case k=0
  • 8.4. The Interpretation Theory When the Well Produces with a Constant Surface Rate
  • 8.4.1. Case for Known Function f(pw1, pw2)
  • 8.4.2. Case for Unknown Function f(pw1, pw2)
  • 8.4.3. Case for f=αD(pwD1-pwD2)
  • 8.4.4. Case for k=0
  • 8.4.5. Limiting Behavior for f=αD(pwD1-pwD2)
  • 8.4.6. Buildup Case
  • 8.4.7. The Determination of Initial Values for Nonlinear Parameter Estimation
  • 8.5. The Influence of Different Parameters on Drawdown Curves
  • 8.5.1. The Influence of the Linear Leakage Rate on Wellbore Pressure
  • 8.5.2. The Influence of Storativity of the Low-Permeability Layer on Wellbore Pressure
  • 8.5.3. The Influence of Wellbore Storage on Wellbore Pressure
  • 8.5.4. The Influence of Semipermeability on Wellbore Pressure
  • 8.5.5. The Influence of Skin Factor on Wellbore Pressure.
  • 8.5.6. The Influence of w1 on Wellbore Pressure
  • 8.5.7. The Influence of Leakage Rates on Wellbore Pressure
  • 8.6. Summary
  • Chapter 9: Unsteady Crossflow Model for Leaky Vertical Interference Testing Across a Low-Permeability Zone
  • 9.1. Introduction
  • 9.2. Model Description
  • 9.3. Relationships of Different Models
  • 9.4. Solution of the Problem
  • 9.4.1. Leakage Function is Known or Has a Linear Form
  • 9.4.2. Leakage Function f is a Nonlinear Unknown Function
  • 9.4.3. Limiting Behavior for f=αD(pwD1-pwD2)
  • 9.4.3.1. Early Time Period
  • 9.4.3.2. Short Time Period
  • 9.4.3.3. Long Time Period
  • 9.5. Interpretation Method of Parameters
  • 9.5.1. Steps of Interpretation
  • 9.5.2. Example of Interpretation
  • 9.6. Comparison of Different Models
  • 9.7. Summary
  • Chapter 10: Material Balance Equation of Multilayer Gas Reservoir
  • 10.1. Material Balance of Two-Layer Gas Reservoir
  • 10.1.1. Physical Model
  • 10.1.2. Mathematical Model of a Two-Layer Gas Reservoir Without Crossflow
  • 10.1.3. Mathematical Model of a Two-Layer Gas Reservoir with Crossflow
  • 10.1.4. p/Z Curve of a Two-Layer Gas Reservoir
  • 10.1.4.1. p/Z Curve of a Two-Layer Gas Reservoir Without Crossflow
  • 10.1.4.2. p/Z Curve of a Two-Layer Gas Reservoir with Crossflow
  • Early Time Period
  • Long Time Period
  • 10.1.5. Influencing Factor Analysis of Reserve Estimation
  • 10.1.5.1. The Effect of an Interlayer Heterogeneity on Dynamic Reserve Estimation
  • 10.1.5.2. The Effect of Crossflow on Dynamic Reserve Estimation
  • 10.1.5.3. The Effect of the Permeability on Reserve Estimation
  • 10.1.6. Method of Improving the Ratio of Dynamic Reserve to OGIP
  • 10.1.6.1. Well Stimulation for Formation with Low Permeability
  • 10.1.6.2. Reduce the Production Output
  • 10.1.6.3. Single-Layer Production for Layer with Low Permeability.
  • 10.2. Reserve Estimation of a Two-Layer Commingled Gas Well.