Numerical Simulation in Hydraulic Fracturing: Multiphysics Theory and Applications

Xinpu Shen, William Standifird

• Publisher: CRC Press
• Year: 2017
• eBook ISBN:
  9781351796286
• Topic: Physical Sciences
• Subtopic: Environmental Science

The expansion of unconventional petroleum resources in the recent decade and the rapid development of computational technology have provided the opportunity to develop and apply 3D numerical modeling technology to simulate the hydraulic fracturing of shale and tight sand formations. This book presents 3D numerical modeling technologies for hydraulic fracturing developed in recent years, and introduces solutions to various 3D geomechanical problems related to hydraulic fracturing. In the solution processes of the case studies included in the book, fully coupled multi-physics modeling has been adopted, along with innovative computational techniques, such as submodeling.
In practice, hydraulic fracturing is an essential project component in shale gas/oil development and tight sand oil, and provides an essential measure in the process of drilling cuttings reinjection (CRI). It is also an essential measure for widened mud weight window (MWW) when drilling through naturally fractured formations; the process of hydraulic plugging is a typical application of hydraulic fracturing. 3D modeling and numerical analysis of hydraulic fracturing is essential for the successful development of tight oil/gas formations: it provides accurate solutions for optimized stage intervals in a multistage fracking job. It also provides optimized well-spacing for the design of zipper-frac wells.
Numerical estimation of casing integrity under stimulation injection in the hydraulic fracturing process is one of major concerns in the successful development of unconventional resources. This topic is also investigated numerically in this book. Numerical solutions to several other typical geomechanics problems related to hydraulic fracturing, such as fluid migration caused by fault reactivation and seismic activities, are also presented.
This book can be used as a reference textbook to petroleum, geotechnical and geothermal engineers, to senior undergraduate, graduate and postgraduate students, and to geologists, hydrogeologists, geophysicists and applied mathematicians working in this field. This book is also a synthetic compendium of both the fundamentals and some of the most advanced aspects of hydraulic fracturing technology.

CHAPTER 1

Introduction to continuum damage mechanics for rock-like materials

Continuum damage mechanics was a part of fracture mechanics at its early stage, but later developed into an independent branch within the framework of solid mechanics. With fracture mechanics, it jointly forms failure mechanics in a wide range of academic domains.

This chapter introduces the fundamental concept and principles of continuum damage mechanics. This introduction is followed by the typical models used in the analysis of geomechanics. The numerical scheme for the calculation of the damage model is also introduced in detail through a typical example.

1.1 INTRODUCTION

Rock-like materials have a complex mechanical behavior, such as anisotropy, hysteresis, dilatancy, irreversible strain, and strongly path-dependent stress-strain relationships. The nonlinear behavior of rock-like materials is generally associated with the existence of many cracks and their propagation.

Micromechanical approaches attempted to predict the macroscale thermomechanical response of heterogeneous materials, based on mesostructural models of a representative volume element (RVE) within the material. Micromechanical models have the distinct advantages of being able to capture structure details at the microscale and mesoscale, and to enable the formulation of the kinetic equation for damage evolution based on the physical process involved. These models, however, can be computationally inefficient in many practical applications and can therefore be applied only to limited cases.

Continuum damage mechanics (CDM) uses continuum variables to describe cracks and joints, thus providing another means of modeling a jointed rock mass. CDM (Lemaitre, 1990) is based on the thermodynamics of irreversible process, internal state variable theory, and relevant physical considerations. Formal CDM modeling of the cracked rock was ...

Table of contents

• Cover Page
• Half Title
• Title Page
• Copyright Page
• About the book series
• Editorial board
• Table of Contents
• Foreword by M.Y. Soliman
• Authors’ preface
• About the authors
• Acknowledgements
• 1 Introduction to continuum damage mechanics for rock-like materials
• 2 Optimizing multistage hydraulic-fracturing design based on 3D continuum damage mechanics analysis
• 3 Numerical analysis of the interaction between two zipper fracture wells using the continuum damage method
• 4 Integrated workflow for feasibility study of cuttings reinjection based on 3D geomechanical analysis and case study
• 5 Geomechanics-based wellbore trajectory optimization for tight formation with natural fractures
• 6 Numerical solution of widened mud weight window for drilling through naturally fractured reservoirs
• 7 Numerical estimation of upper bound of injection pressure window with casing integrity under hydraulic fracturing
• 8 Damage model for reservoir with multisets of natural fractures and its application in the simulation of hydraulic fracturing
• 9 Construction of complex initial stress field and stress re-orientation caused by depletion
• 10 Information transfer software from finite difference grid to finite element mesh
• Nomenclature
• References
• Subject index
• Book series page