Abstract

In order to solve the problem of low accuracy of bottom hole pressure in tight gas reservoir, this paper presents a new way to analyze the bottom hole pressure. By combining literature research and starting from nonlinear motion equations, the model of bottom hole pressure was established through using various mathematical methods such as separation variable method, identity transformation method and differential discrete method. This paper presents a high-precision and high-efficiency method for solving bottom hole pressure in tight gas reservoirs, and a dynamic calculation method for permeability and conductivity is given. Through the sensitivity analysis of the influencing factors of dimensionless pressure and pressure derivative, it is concluded that the larger the power law index is, the larger the warpage of the dimensionless pressure and pressure derivative curve is. The larger the skin coefficient and the wellbore storage coefficient is, the earlier the fluid enters into the quasi-steady-state seepage. When the tight gas reservoir contains closed edges, the resolution points of the dimensionless pressure and pressure derivative curves are obvious with crossing. On the contrary, when the tight gas reservoir contains the constant pressure boundary, the resolution points of the dimensionless pressure and pressure derivative curves are not obvious without crossing.

Highlights

  • Tight gas reservoirs are non-layered superimposed bodies of various types and sizes [1]

  • The numerical mathematical model of the bottom hole pressure is obtained by means of dimensionless transformation, integral transformation method, numerical difference method and chasing method

  • This paper uses Eclipse to simulate the change of bottom hole pressure in a tight gas reservoir

Read more

Summary

Introduction

Tight gas reservoirs are non-layered superimposed bodies of various types and sizes [1]. There are many methods to calculate the bottom hole pressure, such as node analysis method, analytical solution method, numerical solution method and numerical simulation method [3,4,5,6,7,8,9,10,11,12]. 3. The research on the seepage pressure of tight gas reservoirs mainly focuses on the productivity analysis and pressure analysis under constant pressure conditions. The numerical mathematical model of the bottom hole pressure is obtained by means of dimensionless transformation, integral transformation method, numerical difference method and chasing method. Sensitivity analysis is carried out in detail, such as power law index, wellbore storage coefficient, skin factor and the boundary types of tight gas reservoir

Model Establishing
The Conduction Coefficient
The Grid Permeability
Sensitivity Analysis
Wellbore Storage Coefficient
Power Law Exponent
Skin Factor
The Boundary Type of the Tight Gas Reservoir
Findings
Conclusion

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.