Download or read book Hydro mechanical Coupling of Flow in Deformable High aspect Ratio Fractures written by Patrick Schmidt and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Thermo Hydro Mechanical Coupling in Fractured Rock written by Hans-Joachim Kümpel and published by Birkhäuser. This book was released on 2012-12-06 with total page 355 pages. Available in PDF, EPUB and Kindle. Book excerpt: (4). The next three papers extend these views by taking a closer look on parameters that govern hydraulic diffusivity in sandstones and other types of rocks. Specific targets addressed are the influence of differential stress on permeability (5), imaging of the fracture geometry (6), and pressure induced variations in the pore geometry (7). Contributions no. 8 to 10 cover investigations of permeability-porosity relationships during rock evolution (8), of the formation, propagation, and roughness of fractures in a plexi-glass block (9), and pressure oscillation effects of two-phase flow under controlled conditions (10). The subsequent four articles focus on diverse modeling approaches. Issues considered are how the geometry and the mechanical behavior of fractures can be characterized by mathematical expressions (11), how the evolution of permeability in a microcracking rock can be expressed by an analytical model (12), deviations from the cubic law for a fracture of varying aperture (13), and the numerical simulation of scale effects in flow through fractures (14). Three further papers refer to in situ observations, being related to topics as the assessment of in situ permeability from the spatio temporal distribution of an aftershock sequence (15), to the scale dependence of hydraulic pathways in crystalline rock (16), and to the significance of pore pressure - stress coupling in deep tunnels and galleries (17).
Download or read book Rock Fractures and Fluid Flow written by National Research Council and published by National Academies Press. This book was released on 1996-08-27 with total page 568 pages. Available in PDF, EPUB and Kindle. Book excerpt: Scientific understanding of fluid flow in rock fracturesâ€"a process underlying contemporary earth science problems from the search for petroleum to the controversy over nuclear waste storageâ€"has grown significantly in the past 20 years. This volume presents a comprehensive report on the state of the field, with an interdisciplinary viewpoint, case studies of fracture sites, illustrations, conclusions, and research recommendations. The book addresses these questions: How can fractures that are significant hydraulic conductors be identified, located, and characterized? How do flow and transport occur in fracture systems? How can changes in fracture systems be predicted and controlled? Among other topics, the committee provides a geomechanical understanding of fracture formation, reviews methods for detecting subsurface fractures, and looks at the use of hydraulic and tracer tests to investigate fluid flow. The volume examines the state of conceptual and mathematical modeling, and it provides a useful framework for understanding the complexity of fracture changes that occur during fluid pumping and other engineering practices. With a practical and multidisciplinary outlook, this volume will be welcomed by geologists, petroleum geologists, geoengineers, geophysicists, hydrologists, researchers, educators and students in these fields, and public officials involved in geological projects.
Download or read book Thermo Hydro Mechanical Behavior of Conductive Fractures Using a Hybrid Finite Difference Displacement Discontinuity Method written by Mohammadreza Jalali and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Large amounts of hydrocarbon reserves are trapped in fractured reservoirs where fluid flux is far more rapid along fractures than through the porous matrix, even though the volume of the pore space may be a hundred times greater than the volume of the fractures. These are considered extremely challenging in terms of accurate recovery prediction because of their complexity and heterogeneity. Conventional reservoir simulators are generally not suited to naturally fractured reservoirs' production history simulation, especially when production processes are associated with large pressure and temperature changes that lead to large redistribution of effective stresses, causing natural fracture aperture alterations. In this case, all the effective processes, i.e. hydraulic, thermal and geomechanical, should be considered simultaneously to explain and evaluate the behavior of stress-sensitive reservoirs over the production period. This is called thermo-hydro-mechanical (THM) coupling. In this study, a fully coupled thermo-hydro-mechanical approach is developed to simulate the physical behavior of fractures in a plane strain thermo-poroelastic medium. A hybrid numerical method, which implements both the finite difference method (FDM) and the displacement discontinuity method (DDM), is established to study the pressure, temperature, deformation and stress variations of fractures and surrounding rocks during production processes. This method is straightforward and can be implemented in conventional reservoir simulators to update fracture conductivity as it uses the same grid block as the reservoir grids and requires only discretization of fractures. The hybrid model is then verified with couple of analytical solutions for the fracture aperture variation under different conditions. This model is implemented for some examples to present the behavior of fracture network as well as its surrounding rock under thermal injection and production. The results of this work clearly show the importance of rate, aspect ratio (i.e. geometry) and the coupling effects among fracture flow rate and aperture changes arising from coupled stress, pressure and temperature changes. The outcomes of this approach can be used to study the behavior of hydraulic injection for induced fracturing and promoting of shearing such as hydraulic fracturing of shale gas or shale oil reservoirs as well as massive waste disposal in the porous carbonate rocks. Furthermore, implementation of this technique should be able to lead to a better understanding of induced seismicity in injection projects of all kinds, whether it is for waste water disposal, or for the extraction of geothermal energy.
Download or read book GeomInt Discontinuities in Geosystems From Lab to Field Scale written by Olaf Kolditz and published by Springer Nature. This book was released on 2023-05-02 with total page 107 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is an open access book. In view of growing conflicts over strategic georesources, the use of the geological subsurface in the sense of a regional resource is becoming increasingly important. In this context, georeservoirs are playing an important role for the energy transition not only as a source of energy but also as a storage facility and deep geological disposal for energy waste. The success of the energy transition also depends to a large extent on the efficient and safe use of underground resources. This book complements the previous basic book (GeomInt—Integrity of Host Rocks) with a series of application examples in different rock formations, clay, salt, and crystalline. The methodology developed in GeomInt is used, among others, in the Mont Terri underground research laboratory (Opalinus Clay), in the large borehole test in Springen (salt rock) and in the “Reiche Zeche” teaching and research mine (crystalline rock). In addition, new methodological developments are also taken up in experiments and models and embedded in workflows for geotechnical system analyses. The present book summarizes the results of the collaborative project “GeomInt2: Geomechanical integrity of host and barrier rocks - experiment, modeling and analysis of discontinuities” within the program: Geo Research for Sustainability (GEO: N) of the Federal Ministry of Education and Research (BMBF).
Download or read book Structurally Complex Reservoirs written by S. J. Jolley and published by Geological Society of London. This book was released on 2007 with total page 508 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Hardrock Tunnel Boring Machines written by Bernhard Maidl and published by John Wiley & Sons. This book was released on 2012-01-09 with total page 372 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book covers the fundamentals of tunneling machine technology: drilling, tunneling, waste removal and securing. It treats methods of rock classification for the machinery concerned as well as legal issues, using numerous example projects to reflect the state of technology, as well as problematic cases and solutions. The work is structured such that readers are led from the basics via the main functional elements of tunneling machinery to the different types of machine, together with their areas of application and equipment. The result is an overview of current developments. Close cooperation among the authors involved has created a book of equal interest to experienced tunnelers and newcomers.
Download or read book Advances in Hydraulic Fracture Simulation Dynamic and Quasi static Analysis written by Matin Parchei Esfahani and published by . This book was released on 2019 with total page 170 pages. Available in PDF, EPUB and Kindle. Book excerpt: Hydraulic fracturing (HF) is an effective technique for permeability enhancement of conventional and unconventional reservoirs. HF is performed by injecting a fluid (usually water-based), sand, and chemicals into a formation under high pressure in order to induce damage and improve the interconnectivity of the fracture network through reopening of natural fractures and generation of new fractures. Hydraulic fracturing is a complex multi-physics process that involves the coupling of several physical phenomena, such as rock deformation, fluid flow, fracture propagation, etc. The simulation of HF is complex due to its coupled multi-physics nature. Despite recent advancements in HF simulations, relatively little attention has been given to improving the coupling algorithms used in these simulations. In many cases, sequential coupling algorithms are preferred over the monolithic approach due to the availability of independent solvers for each subproblem (e.g., independent deformable solid and fluid flow models), and the costliness of the monolithic approach. However, the available sequential algorithms widely used in the simulation of hydraulic fractures are known to lack robustness and encounter stability and/or convergence issues. The unavailability of efficient and effective sequential algorithms for the simulation of hydraulic fractures is currently one of the major gaps in the literature. The majority of hydraulic fracture models use quasi-static analysis, which neglects the inertial effects that are important when injection rates are very high or vary quickly in time, as during stimulation by pressure pulsing. The application of the dynamic models currently available in the literature is mainly limited to the dynamic simulations of acoustic wave emissions in porous media. Very few studies, until now, have considered dynamic simulation of fluid driven fractures. Hence, the unavailability of reliable dynamic hydraulic fracture models is another major gap in the hydraulic fracture literature. This thesis has three objectives. The first objective is to develop a stable sequential coupling algorithm for enforcing the hydro-mechanical coupling in the simulation of hydraulic fractures. The focus of the first objective is on the sequential algorithms that solve the mechanics subproblem first, in each iteration. This objective is realized in Chapter 2 of the thesis. The split is derived using the analogy of the undrained split in poromechanics; hence the new algorithm is named the \emph{undrained HF split}. The undrained HF split converges to the solution of the fully coupled (monolithic) approach. It's also shown to be stable and convergent in applications in which the conventional coupling strategies fail to converge due to oscillations. The convergence of the undrained HF split is generally slower than the fully coupled model. The second objective of the thesis is to develop a stable sequential coupling algorithm that solves the fluid flow subproblem first, in each iteration. This objective is addressed in Chapter 3 of the thesis. This algorithm is derived using the analogy of the fixed stress split in poromechanics and, therefore, named the \emph{fixed stress HF split}. The fixed stress HF split is stable and shown to converge to the solution of the fully coupled model. The algorithm is shown to successfully simulate nonplanar hydraulic fracture trajectories in flow rate controlled hydraulic fracture simulations. The third objective of the thesis is to develop a dynamic hydraulic fracture model for investigating the effect of rapidly changing loads, such as those caused by pressure pulses, on the dynamic propagation of hydraulic fractures. Chapter 4 of the thesis addresses this objective. A dynamic HF model with leak-off is developed in Chapter 4. The dynamic HF model is used to study wellbore stimulation by high rate and high amplitude pressure pulses and investigate the effect of formation porosity and permeability on the dynamic response of the system. It is observed that generally, formations with higher porosity and permeability generate shorter and wider hydraulic fractures. The dynamic response of hydraulic fractures is found to contain a phase lag with respect to the applied pressure pulse, which slightly increases with an increase in the porosity and permeability of the formation. Fracture closure mechanism is directly affected by the rate of fluid leak-off from hydraulic fractures, which also depends on the porosity and permeability of the formation. Unique acoustic wave emission patterns are observed from the response of hydraulic fracture and wellbore system to the pressure pulse at each stage of the stimulation.
Download or read book Mechanics of Hydraulic Fracturing written by Ching H. Yew and published by Gulf Professional Publishing. This book was released on 2014-09-25 with total page 245 pages. Available in PDF, EPUB and Kindle. Book excerpt: Revised to include current components considered for today’s unconventional and multi-fracture grids, Mechanics of Hydraulic Fracturing, Second Edition explains one of the most important features for fracture design — the ability to predict the geometry and characteristics of the hydraulically induced fracture. With two-thirds of the world’s oil and natural gas reserves committed to unconventional resources, hydraulic fracturing is the best proven well stimulation method to extract these resources from their more remote and complex reservoirs. However, few hydraulic fracture models can properly simulate more complex fractures. Engineers and well designers must understand the underlying mechanics of how fractures are modeled in order to correctly predict and forecast a more advanced fracture network. Updated to accommodate today’s fracturing jobs, Mechanics of Hydraulic Fracturing, Second Edition enables the engineer to: Understand complex fracture networks to maximize completion strategies Recognize and compute stress shadow, which can drastically affect fracture network patterns Optimize completions by properly modeling and more accurately predicting for today’s hydraulic fracturing completions Discusses the underlying mechanics of creating a fracture from the wellbore Enhanced to include newer modeling components such as stress shadow and interaction of hydraulic fracture with a natural fracture, which aids in more complex fracture networks Updated experimental studies that apply to today’s unconventional fracturing cases
Download or read book Porous Rock Fracture Mechanics written by Amir Shojaei and published by Woodhead Publishing. This book was released on 2017-05-05 with total page 337 pages. Available in PDF, EPUB and Kindle. Book excerpt: Porous Rock Failure Mechanics: Hydraulic Fracturing, Drilling and Structural Engineering focuses on the fracture mechanics of porous rocks and modern simulation techniques for progressive quasi-static and dynamic fractures. The topics covered in this volume include a wide range of academic and industrial applications, including petroleum, mining, and civil engineering. Chapters focus on advanced topics in the field of rock’s fracture mechanics and address theoretical concepts, experimental characterization, numerical simulation techniques, and their applications as appropriate. Each chapter reflects the current state-of-the-art in terms of the modern use of fracture simulation in industrial and academic sectors. Some of the major contributions in this volume include, but are not limited to: anisotropic elasto-plastic deformation mechanisms in fluid saturated porous rocks, dynamics of fluids transport in fractured rocks and simulation techniques, fracture mechanics and simulation techniques in porous rocks, fluid-structure interaction in hydraulic driven fractures, advanced numerical techniques for simulation of progressive fracture, including multiscale modeling, and micromechanical approaches for porous rocks, and quasi-static versus dynamic fractures in porous rocks. This book will serve as an important resource for petroleum, geomechanics, drilling and structural engineers, R&D managers in industry and academia. Includes a strong editorial team and quality experts as chapter authors Presents topics identified for individual chapters are current, relevant, and interesting Focuses on advanced topics, such as fluid coupled fractures, rock’s continuum damage mechanics, and multiscale modeling Provides a ‘one-stop’ advanced-level reference for a graduate course focusing on rock’s mechanics
Download or read book Discrete Fracture Network Modeling of Hydraulic Stimulation written by Mark W. McClure and published by Springer Science & Business Media. This book was released on 2013-06-15 with total page 96 pages. Available in PDF, EPUB and Kindle. Book excerpt: Discrete Fracture Network Modeling of Hydraulic Stimulation describes the development and testing of a model that couples fluid-flow, deformation, friction weakening, and permeability evolution in large, complex two-dimensional discrete fracture networks. The model can be used to explore the behavior of hydraulic stimulation in settings where matrix permeability is low and preexisting fractures play an important role, such as Enhanced Geothermal Systems and gas shale. Used also to describe pure shear stimulation, mixed-mechanism stimulation, or pure opening-mode stimulation. A variety of novel techniques to ensure efficiency and realistic model behavior are implemented, and tested. The simulation methodology can also be used as an efficient method for directly solving quasistatic fracture contact problems. Results show how stresses induced by fracture deformation during stimulation directly impact the mechanism of propagation and the resulting fracture network.
Download or read book New numerical approaches to model hydraulic fracturing in tight reservoirs with consideration of hydro mechanical coupling effects written by Lei Zhou and published by Cuvillier Verlag. This book was released on 2014-03-20 with total page 172 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this dissertation, two new numerical approaches for hydraulic fracturing in tight reservoir were developed. A more physical-based numerical 3D-model was developed for simulating the whole hydraulic fracturing process including fracture propagation, closure and contact as well as proppant transport and settling. In this approach rock formation, pore and fracture systems were assembled together, in which hydro-mechanical coupling effect, proppant transport and settling as well as their influences on fracture closure and contact were fully considered. A combined FDM and FVM schema was used to solve the problem. Three applications by using the new approach were presented. The results illustrated the whole hydraulic fracturing process well and seemed to be logical, which confirmed the ability of the developed approach to model the in-situ hydraulic fracturing operation from injection start till fully closure. In order to investigate the orientation problem of hydraulic fracturing in tight reservoir, a new approach for simulating arbitrary fracture propagation and orientation in 2D was developed. It was solved by a hybrid schema of XFEM and FVM. Three numerical studies were illustrated, which proved the ability of the developed approach to solve the orientation problem in field cases.
Download or read book Coupled Thermo Hydro Mechanical Processes of Fractured Media written by O. Stephanson and published by Elsevier. This book was released on 1997-02-10 with total page 597 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work brings together the results, information and data that emerged from an international cooperative project, DECOVALEX, 1992-1995. This project was concerned with the mathematical and experimental studies of coupled thermo(T) -hydro(H) -mechanical(M) processes in fractured media related to radioactive waste disposal. The book presents, for the first time, the systematic formulation of mathematical models of the coupled T-H-M processes of fractured media, their validation against theoretical bench-mark tests, and experimental studies at both laboratory and field scales. It also presents, for the first time, a comprehensive analysis of continuum, and discrete approaches to the study of the problems of (as well as a complete description of), the computer codes applied to the studies. The first two chapters provide a conceptual introduction to the coupled T-H-M processes in fractured media and the DECOVALEX project. The next seven chapters give a state-of-the-art survey of the constitutive models of rock fractures and formulation of coupled T-H-M phenomena with continuum and discontinuum approaches, and associated numerical methods. A study on the three generic Bench-Mark Test problems and six Test Case problems of laboratory and field experiments are reported in chapters 10 to 18. Chapter 19 contains lessons learned during the project. The research contained in this book will be valuable for designers, practising engineers and national waste management officials who are concerned with planning, design and performance, and safety assessments of radioactive waste repositories. Researchers and postgraduate students working in this field will also find the book of particular relevance.
Download or read book Optimization of Multistage Hydraulic Fracturing Treatment for Maximization of the Tight Gas Productivity written by Mengting Li and published by Cuvillier Verlag. This book was released on 2018-12-17 with total page 208 pages. Available in PDF, EPUB and Kindle. Book excerpt: Hydraulic fracturing is essential technology for the development of unconventional resources such as tight gas. So far, there are no numerical tools which can optimize the whole process from geological modeling, hydraulic fracturing until production simulation with the same 3D model with consideration of the thermo-hydro-mechanical coupling. In this dissertation, a workflow and a numerical tool chain were developed for design and optimization of multistage hydraulic fracturing in horizontal well regarding a maximum productivity of the tight gas wellbore. After the verification a full 3D reservoir model is generated based on a real tight gas field in the North German Basin. Through analysis of simulation results, a new calculation formula of FCD was proposed, which takes the proppant position and concentration into account and can predict the gas production rate more accurately. However, not only FCD but also proppant distribution and hydraulic connection of stimulated fractures to the well, geological structure and the interaction between fractures are determinant for the gas production volume. Through analysis the numerical results of sensitivity analysis and optimization variations, there is no unique criterion to determine the optimal number and spacing of the fractures, it should be analyzed firstly in detail to the actual situation and decided then from case to case.
Download or read book Mechanics of Fluid Saturated Rocks written by Yves Gueguen and published by Elsevier. This book was released on 2004-05-12 with total page 465 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mechanics of Fluid Saturated Rocks presents a current and comprehensive report on this emerging field that bridges the areas of geology and mechanics. It is of direct interest to a wide spectrum of earth scientists and engineers who are concerned with upper-crust mechanics and fluid movements, the most important fluids being oil and water. This authoritative book is the result of a collaborative effort between scientists in academic institutions and industry. It examines important issues such as subsidence, geological fault formation, earthquake faulting, hydraulic fracturing, transport of fluids, and natural and direct applications. Mechanics of Fluid Saturated Rocks provides a unique interdisciplinary viewpoint, as well as case studies, conclusions, and recommendations for further research. Covers the physical, chemical, and mechanical analysis of porous saturated rock deformation on both large and small scales Discusses the latest developments of importance to engineers and geologists Examines natural and direct applications Includes extensive bibliographies for each chapter
Download or read book Fractured Porous Media written by Pierre M. Adler and published by Oxford University Press, USA. This book was released on 2013 with total page 184 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a systematic treatment of the geometrical and transport properties of fractures, fracture networks, and fractured porous media. It is divided into two major parts. The first part deals with geometry of individual fractures and of fracture networks. The use of the dimensionless density rationalizes the results for the percolation threshold of the networks. It presents the crucial advantage of grouping the numerical data for various fracture shapes. The second part deals mainly with permeability under steady conditions of fractures, fracture networks, and fractured porous media. Again the results for various types of networks can be rationalized by means of the dimensionless density. A chapter is dedicated to two phase flow in fractured porous media.
Download or read book Hydraulic Fracture Mechanics written by Peter Valkó and published by . This book was released on 1995 with total page 328 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book explores the theoretical background of one of the most widespread activities in hydrocarbon wells, that of hydraulic fracturing. A comprehensive treatment of the basic phenomena includes: linear elasticity, stresses, fracture geometry and rheology. The diverse concepts of mechanics are integrated into a coherent description of hydraulic fracture propagation. The chapters in the book are cross-referenced throughout and the connections between the various phenomena are emphasized. The book offers readers a unique approach to the subject with the use of many numerical examples.
