Next Article in Journal
Tip-Bed Velocity and Scour Depth of Horizontal-Axis Tidal Turbine with Consideration of Tip Clearance
Previous Article in Journal
An Iterative Methodology for Model Complexity Reduction in Residential Building Simulation
Article Menu
Issue 12 (June-2) cover image

Export Article

Open AccessArticle

Pseudo-Steady-State Parameters for a Well Penetrated by a Fracture with an Azimuth Angle in an Anisotropic Reservoir

1
Research Institute of Petroleum Exploration and Development, China National Petroleum Corporation, Beijing 100083, China
2
State Key Laboratory of Enhanced Oil Recovery, Ministry of Science and Technology, Beijing 100083, China
*
Author to whom correspondence should be addressed.
Energies 2019, 12(12), 2449; https://doi.org/10.3390/en12122449
Received: 7 May 2019 / Revised: 15 June 2019 / Accepted: 21 June 2019 / Published: 25 June 2019
(This article belongs to the Section Geo-Energy)
  |  
PDF [5074 KB, uploaded 25 June 2019]
  |  

Abstract

Many oil wells in closed reservoirs continue to produce in the pseudo-steady-state flow regime for a long time. The principal objective of this work is to investigate the characteristics of two key pseudo-steady-state parameters—pseudo-steady-state constant (bDpss) and pseudo-skin factor (S)—for a well penetrated by a fracture with an azimuth angle (θ) in an anisotropic reservoir. Firstly, a general analytical pressure solution for a finite-conductivity fracture with or without an azimuth angle in an anisotropic rectangular reservoir was developed by using the point-source function and spatial integral method, and two typical cases were employed to verify this solution. Secondly, with the asymptotic analysis method, the expressions of pseudo-steady-state constant and pseudo-skin factor were obtained on the basis of their definitions, and the effects of permeability anisotropy, fracture azimuth angle, fracture conductivity and reservoir shape on them were discussed in detail. Results show that all the bDpss-θ and S-θ curves are symmetric around the vertical line, θ = 90° and form a hump or groove shape. The optimized fracture direction in an anisotropic reservoir is perpendicular to the principal permeability axis. Furthermore, a new formula to calculate pseudo-skin factor was successfully proposed based on these two parameters’ relationship. Finally, as an application of pseudo-steady-state constant, a set of Blasingame format rate decline curves for the proposed model were established. View Full-Text
Keywords: pseudo-steady-state flow; anisotropic reservoir; fracture azimuth angle; pseudo-steady-state constant; pseudo-skin factor; Blasingame format decline curves pseudo-steady-state flow; anisotropic reservoir; fracture azimuth angle; pseudo-steady-state constant; pseudo-skin factor; Blasingame format decline curves
Figures

Figure 1

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited (CC BY 4.0).
SciFeed

Share & Cite This Article

MDPI and ACS Style

Xing, G.; Wang, M.; Wu, S.; Li, H.; Dong, J.; Zhao, W. Pseudo-Steady-State Parameters for a Well Penetrated by a Fracture with an Azimuth Angle in an Anisotropic Reservoir. Energies 2019, 12, 2449.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics

1

Comments

[Return to top]
Energies EISSN 1996-1073 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top