A5053482507- Hydraulic Fracturing and Reservoir Analysis
- Reservoir Engineering and Simulation Methods
- Drilling and Well Engineering
- Enhanced Oil Recovery Techniques
- Groundwater flow and contamination studies
- Seismic Imaging and Inversion Techniques
- Geothermal Energy Systems and Applications
- Hydrocarbon exploration and reservoir analysis
- Oil and Gas Production Techniques
- CO2 Sequestration and Geologic Interactions
- Geophysical and Geoelectrical Methods
- Rock Mechanics and Modeling
- NMR spectroscopy and applications
- earthquake and tectonic studies
- Advanced Mathematical Modeling in Engineering
- Geological Modeling and Analysis
- Advanced Numerical Methods in Computational Mathematics
- Geochemistry and Geologic Mapping
- Geophysical Methods and Applications
- Seismology and Earthquake Studies
- Soil and Unsaturated Flow
- Heat and Mass Transfer in Porous Media
- Water resources management and optimization
- Heat Transfer and Boiling Studies
- Flow Measurement and Analysis
Stanford University
2016-2025
Pacific Northwest National Laboratory
2016
Jilin University
2015
Jilin Medical University
2015
Environmental and Water Resources Engineering
2011-2012
Peking University
2006
Government of the United States of America
1985
The Ohio State University
1982
Stanford Medicine
1981
University of Auckland
1974-1979
We review ten historical Enhanced Geothermal Systems (EGS) projects and find that typically, during injection: (1) flow from the wellbore is preexisting fractures, (2) bottomhole pressure exceeds minimum principal stress, (3) pressure-limiting behavior occurs. These observations are apparently contradictory because consistent with shear stimulation, but suggest propagation of new fractures. To reconcile these observations, we propose that, in many cases, fractures do not form at wellbore,...
We describe a numerical investigation of seismicity induced by injection into single isolated fracture. Injection fracture is simple analog for shear stimulation in enhanced geothermal systems (EGS) during which water injected fractured, low permeability rock, triggering slip on preexisting large scale zones. A model was developed and used that couples (1) fluid flow, (2) rate state friction, (3) mechanical stress interaction between elements. Based the results this model, we propose...
Abstract Optimization of reservoir development requires many evaluations the possible combinations decision variables, such as properties, well locations and production scheduling parameters. to obtain best economical strategies. Running a simulator for large number may be impractical due computation time involved. In this study, hybrid Genetic Algorithm (GA) was developed. The optimization algorithm integrated economic analysis, simulation project design. layout 33 new wells real oil field...
Abstract This paper presents an algorithm to compute transmissibility when there is permeability heterogeneity and anisotropy at the subgrid scale. The need for a tensor representation of macroscopic in order scale properly effects microscale variations demonstrated. Methods computing use reservoir simulation are described. proposed method applicable even variance large principal directions not aligned with coordinate axes. Examples demonstrate that general scaling procedure can give...
The stability of natural convective flow in a porous medium heated both uniformly and non-uniformly from below is studied order to determine the possibility oscillatory other unsteady flows, explore conditions under which they may occur. results numerical work are directly comparable with experiments using Hele Shaw cell also, case, Combarnous & Le Fur (1969) Caltagirone, Cloupeau (1971). It shown that for problem there exist, certain cases, two distinct possible modes flow, one...
The Fenton Hill enhanced geothermal system (EGS) test site was the first of its kind, and interpretations field observations from project have influenced past four decades EGS development. In this study, we hypothesized that stimulation (i.e., permeability enhancement) in reservoir occurred through a mixed-mechanism process involved propagation hydraulic splay fractures encouraged by stress changes induced as natural opened failed shear. We used hydromechanical fractured numerical model to...
Abstract Despite the wide application of hydraulic fracturing in enhanced geothermal system (EGS) development and unconventional hydrocarbon production, our understanding many factors affecting propagation fractures has relied on circumstantial evidence. This is partly due to scarcity direct observations subsurface. The EGS Collab project attempts address these issues context research by performing intermediate‐scale (∼10 m) stimulation experiments a thoroughly characterized heavily...
Geothermal energy provides clean, steady and renewable electricity heat, but the use of geothermal has conventionally been constrained to locations with adequate subsurface heat fluid flow. Enhanced systems (EGS) enable usage in unconventional areas by enhancing permeability increasing flow, which is then extracted as a carrier thermal energy. In this Review, we discuss development EGS its role providing Some are operating commercially Europe provide and/or electricity, technical issues...
We forecasted 82 GW of total geothermal capacity by 2045, reducing system and costs 40% 8.6%, respectively.
Abstract This paper deals with the problem of estimating distributions permeability and porosity in heterogeneous multiphase petroleum reservoirs by matching dynamic behavior. The data is form field measurements from well testing, production history, interpreted 4-D seismic information, other such as correlations between porosity, geostatistics a variogram model inference large scale geological structure. issue was posed an inverse solved using nonlinear parameter estimation. procedure...
The Brooks and Corey relative permeability model has been accepted widely as a way to calculate using capillary pressure data. However, the Purcell was found be best fit experimental data of wetting‐phase in cases studied here, long measured curve had same residual saturation curve. differences between calculated for wetting phase were almost negligible. A physical developed explain insignificance effect tortuosity on calculation permeability. For nonwetting‐phase, permeabilities models very...
Summary A method has been developed to characterize the process of spontaneous water imbibition into gas-saturated rocks. Water relative permeability and capillary pressure can be calculated simultaneously from data using this method. linear relationship between rate reciprocal gas recovery by was found confirmed both theoretically experimentally, even at different initial saturations. There almost no effect saturation on residual imbibition. The higher saturation, lower ultimate recovery....
Summary A method was developed to scale the experimental data of spontaneous water imbibition (cocurrent) for gas/water/rock systems. In this method, a dimensionless time defined with effects relative permeability, wettability, and gravity included. The definition not empirical but based on theoretical derivation. Using time, from in different rocks size, porosity, initial saturation, interfacial tension, wettability might be scaled. scaling model proposed study systems verified...
Summary Scaling the experimental data of spontaneous imbibition without serious limitations has been difficult. To this end, a general approach was developed to scale for most systems (gas/liquid/rock and oil/water/ rock systems) in both cocurrent countercurrent cases. We defined dimensionless time with almost all parameters considered. These include porosity, permeability, size, shape, boundary conditions, wetting- nonwetting-phase relative permeabilities, interfacial tension (IFT),...
Summary Permanent downhole gauges (PDGs) provide a continuous source of pressure, temperature, and sometimes flow-rate data. Until recently, the measured temperature data have been largely ignored, although close observation measurements reveals response to changes in flow rate pressure. This suggests that may be useful reservoir information. In this study, temperature-transient models were developed for single- multiphase-fluid flows, as functions formation parameters, fluid properties, The...
A numerical modeling framework is described that able to calculate the coupled processes of fluid flow, geomechanics, and rock failure for application general engineering problems related reservoir stimulation, including hydraulic fracturing shear stimulation. The formulation employs use an embedded fracture approach, which provides several advantages over more traditional methods in terms computational complexity efficiency. Specifically, strategy avoids usual requirement discretization...
The impact of anisotropy within spatially-varying fracture apertures on heat transfer in the context Enhanced Geothermal Systems was investigated. anisotropic aperture distributions studied included samples from laboratory-scale fractures and additional 100 artificial generated using Sequential Gaussian Simulation. Two flow configurations were perpendicular configuration had a to lateral shear offset direction, while parallel direction. thermal performance simulated numerically...
Abstract Determining the best location for new wells is a complex problem that depends on reservoir and fluid properties, well surface equipment specifications, economic criteria. Numerical simulation often most appropriate tool to evaluate feasibility of configurations. However, since data used establish numerical models have uncertainty, so do model forecasts. The uncertainties in reflect themselves outcomes configuration decisions. We never possess true deterministic information about but...
Summary In this study, a hybrid optimization technique based on the genetic algorithm (GA), polytope algorithm, kriging and neural networks is proposed to optimize waterflooding project. Hybridization of GA with these helper methods introduces hill climbing into stochastic search makes use proxies created fly. It was observed that number simulations required reduced significantly, as compared conventional approaches. This reduction in computation time, enabling full-scale simulation for even...
Abstract An analytical model has been developed to describe the inflow performance and transient pressure behavior of a horizontal well with multiple hydraulic fractures. The used compare relative productivities fractures, objective being determine conditions under which fractures provide significant improvement over single fracture. approach was approximate series as fully penetrating, uniform flux, vertical in box-shaped reservoir closed boundaries. Interference between accounted for by...
Summary Determining the best location for new wells is a complex problem that depends on reservoir and fluid properties, well surface-equipment specifications, economic criteria. Numerical simulation often most appropriate tool to evaluate feasibility of configurations. However, because data used establish numerical models have uncertainty, so do model forecasts. The uncertainties in reflect themselves outcomes well-configuration decisions. We never possess true deterministic information...
Interpretation of tracer tests is commonly based on the analysis flow through a porous medium. In geothermal reservoirs however principal permeability arises from fractures, and medium approach not applicable. The dispersion material flowing in fracture shown to be dominated by molecular diffusion across ‐ mechanism known as Taylor dispersion. For typical values reservoir parameters, this transverse will obliterate any concentration gradients caused velocity profile fracture. effective...