PREDICTING EQUILIBRIUM PRESSURES FROM TRANSIENT PRESSURE DATA

1965 ◽  
Author(s):  
David L. Brown
Keyword(s):  
Pressure Data ◽  
Transient Pressure

scholarly journals The Effect of Rheology of Viscoelastic Polymer on Pressure Transient Response in Near-Wellbore Regions

Geofluids ◽  
2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
Jia Zhang ◽  
Shiqing Cheng ◽  
Jie Zhan ◽  
Qi Han
Keyword(s):  
Shear Thickening ◽  
Shear Thinning ◽  
Polymer Flooding ◽  
High Shear ◽  
Pressure Data ◽  
Transient Pressure ◽  
Pressure Derivative ◽  
Shear Rates ◽  
Viscoelastic Polymer ◽  
Thickening Behavior

Viscoelastic polymer solution shows shear thinning behavior at low shear rates and shear thickening behavior at high shear rates in reservoirs. However, models that ignored shear thickening behavior were commonly employed to interpret transient pressure data derived from tested wells in viscoelastic polymer flooding systems; although, viscoelastic polymer solutions show shear thickening behavior in the near-wellbore region due to high shear rate. To better characterize the oilfield with pressure transient analysis in viscoelastic polymer flooding systems, we developed a numerical model that takes into account both shear thinning behavior and shear thickening behavior. A finite volume method was employed to discretize partially differential flow equations in a hybrid grid system including PEBI mesh and Cartesian grid, and the Newton-Raphson method was used to solve the fully implicit nonlinear system. To illustrate the significance of our model, we compared our model with a model that ignores the shear thickening behavior by graphing their solutions on log-log plots. In the flow regime of near-wellbore damage, the pressure derivative computed by our model is distinctly larger than that computed by the model ignoring shear thickening behavior. Furthermore, the effect of shear thickening behavior on pressure derivative differs from that of near-wellbore damage. We then investigated the influence of shear thickening behavior on pressure derivative with different polymer injection rates, injection rates, and permeabilities. The results can provide a benchmark to better estimate near-wellbore damage in viscoelastic polymer flooding systems. Besides, we demonstrated the applicability and accuracy of our model by interpreting transient pressure data from a field case in an oilfield with viscoelastic polymer flooding treatments.

scholarly journals Construction of a carbonate reservoir model using transient pressure data

2009 ◽  
Vol 36 (6) ◽  
pp. 762-767 ◽  
Author(s):  
Seyed Sadegh Taheri Rudsari ◽  
Mohammad Bagher Ghanizadeh ◽  
Manuchehr Haghighi
Keyword(s):  
Carbonate Reservoir ◽  
Pressure Data ◽  
Transient Pressure ◽  
Reservoir Model

Calibration of High-Resolution Reservoir Models Using Transient Pressure Data

2009 ◽  
Author(s):  
Jong Uk Kim ◽  
Akhil Datta-Gupta ◽  
Roald Brouwer ◽  
Byron Haynes
Keyword(s):  
High Resolution ◽  
Pressure Data ◽  
Transient Pressure ◽  
Reservoir Models

Transient Pressure Behavior for a Well With a Finite-Conductivity Vertical Fracture

1978 ◽  
Vol 18 (04) ◽  
pp. 253-264 ◽  
Author(s):  
Heber Cinco L. ◽  
F. Samaniego V. ◽  
N. Dominguez A.
Keyword(s):  
Early Time ◽  
Curve Analysis ◽  
Hydraulic Fractures ◽  
Finite Conductivity ◽  
Pressure Data ◽  
Transient Pressure ◽  
Type Curve ◽  
Fracture Characteristics ◽  
Vertical Fracture ◽  
Pressure Behavior

Abstract A mathematical model was developed to study the transient behavior of a well with a finite-conductivity vertical fracture in an infinite slab reservoir. For values of dimensionless time of interest, to >10, the dimensionless wellbore pressure, p, can be correlated by the dimensionless group; wk / x k, where w, k, and x are the width, permeability, and half length of the fracture, respectively, and k represents the formation permeability. Results when plotted as a function of P vs log to give, for large t, a 1.151-slope straight line; hence, semilogarithmic pressure analysis methods can be applied. When plotted in terms o/ log P vs log t, a family of curves of characteristic shape result. A type-curve matching procedure can be used to analyze early time transient procedure can be used to analyze early time transient pressure data to obtain the formation and fracture pressure data to obtain the formation and fracture characteristics. Introduction Hydraulic fracturing is an effective technique for increasing the productivity of damaged wells or wells producing from low permeability formations. Much research has been conducted to determine the effect of hydraulic fractures on well performance and transient pressure behavior. The results have been used to improve the design of hydraulic fractures. Many methods have been proposed to determine formation properties and fracture characteristics from transient pressure and flow rate data. These methods have been based on either analytical or numerical solutions of the transient flow of fluids toward fractured wells. Recently, Gringarten et al. made an important contribution to the analysis of transient pressure data of fractured wells. They presented a type-curve analysis and three basic presented a type-curve analysis and three basic solutions: the infinite-fracture conductivity solution (zero pressure drop along a vertical fracture the uniform flux solution for vertical fractures, and the uniform flux solution for horizontal fractures. Although the assumption of an infinite fracture conductivity is adequate for some cases, we must consider a finite conductivity for large or very low flow capacity fractures. Sawyer and Locke studied the transient pressure behavior of finite-conductivity vertical fractures in gas wells. Their solutions cannot be used to analyze transient pressure data because only specific cases were presented. In this study, we wanted to prepare general solutions for the transient pressure behavior of a well intersected by a finite-conductivity vertical fracture. The solutions sought should be useful for short-time or type-curve analysis. We also wanted to show whether conventional methods could be applied to analyze transient pressure data for these conditions. A combination of both methods, as pointed out by Gringarten to al., should permit an pointed out by Gringarten to al., should permit an extraordinary confidence level concerning the analysis of field data. STATEMENT OF THE PROBLEM AND DEVELOPMENT OF FLOW MODELS The transient pressure behavior for a fractured well can be studied by analyzing the solution of the differential equations that describe this phenomenon with proper initial and boundary conditions. To simplify the derivation of flow models, the following assumptions are made.An isotropic, homogeneous, horizontal, infinite, slab reservoir is bounded by an upper and a lower impermeable strata. The reservoir has uniform thickness, h, permeability, k, and porosity, which are independent of pressure.The reservoir contains a slightly compressible fluid of compressibility, c, and viscosity, mu, and both properties are constant.Fluid is produced through a vertically fractured well intersected by a fully penetrating, finite-conductivity fracture of half length, x, width, w, permeability, k, and porosity, phi . These fracture permeability, k, and porosity, phi . These fracture characteristics are constant. Fluid entering the wellbore comes only through the fracture. A system with these assumptions is shown in Fig. 1. In addition, we assume that gravity effects are negligible and also that laminar flow occurs in the system.

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