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Podgorney, Robert K.

Publications and source records attributed to Podgorney, Robert K..

FY 2021 Mid-Year HPC Utilization Report M3UF-21IN0701018

Idaho National Laboratory (INL), supported by the Department of Energy Office of Nuclear Energy (DOE-NE) through the Nuclear Science User Facilities, provides access to supercomputer systems and data storage along with support staff for system management, software installation, cybersecurity and user support to the broader DOE-NE user community. Users include individuals at universities, industry, and government laboratories enabling a wide range of research and development and mission-supporting activities. The availability of high-performance computing (HPC) capabilities is a key foundation of collaboration and innovation in nuclear energy systems research. HPC resources and INL directly support the mission and objectives of DOE-NE. From October 2020 through March 2021, INL HPC capabilities were utilized by a diverse set of computing and applied researchers, for a wide range of research and engineering activities. This report focuses on current INL HPC systems and utilization from October 1, 2020 through March 31, 2021.

99 GENERAL AND MISCELLANEOUS↗

EGS Collab Project: Accomplishments and Plan

To better understand stimulation and inter-well flow in crystalline rock with the goal of developing and improving subsurface heat exchangers for enhanced geothermal energy recovery, the EGS (Enhanced Geothermal Systems) Collab project is developing highly monitored, well- characterized intermediate scale (~10-20 m) field test beds, stimulating, and performing flow tests. These tests provide the ability to evaluate concepts, data to test and validate models, and tools to be used for EGS development, which may be evaluated at DOE’s Frontier Observatory for Research in Geothermal Energy (FORGE) project. Numerical simulation is key to the project, for experiment design and interpretation of results. Testbed characterization included optical and acoustic televiewers, full waveform seismic, electromagnetic, gamma, and temperature. The test block was further characterized using seismic tomography (p- and s-), electrical resistance tomography (ERT), and hydrologic characterization including tracer tests. Coupled process models are constrained by the detailed site characterization data. Installed monitoring systems include: 1) passive seismic/acoustic emissions; 2) continuous active source seismic; 3) ERT, with dynamic imaging using high contrast fluids; and 4) distributed acoustic, temperature, and strain fiber optic sensors. During flow and stimulation tests, fracture aperture strain monitoring is performed using the Step-rate Injection Method for Fracture In-situ Properties (SIMFIP) tool. Pressure and flow in the injection and production boreholes are monitored, and tracer tests and wavefield imaging and inversion are performed to provide additional constraints. Stimulations have been performed at several locations, connecting our injection and production wells. An overview of the EGS Collab project is presented to provide a framework for other EGS Collab presentations, along with results from numerical simulations and experiments performed at the Sanford Underground Research Facility in South Dakota.

Enhanced Geothermal Systems, EGS Collab, stimulati↗

EGS Collab Project Experiment 1 Overview and Progress

Enhanced Geothermal Systems (EGS) offer the potential to extract and use large quantities of clean energy, but questions remain on reservoir creation and sustainability. The EGS Collab project, supported by the US Department of Energy’s Geothermal Technologies Office, is establishing a suite of highly monitored and well-characterized intermediate-scale (~10-20 m) field test beds along with fracture stimulation and interwell flow tests to better understand processes that control formation of effective subsurface heat exchangers. EGS Collab tests will provide a means of testing tools and concepts that could later be employed under geothermal reservoir conditions at DOE’s Frontier Observatory for Research in Geothermal Energy (FORGE) or enhanced geothermal systems. Key to the project is using numerical simulations in the experiment design and interpretation of results. Our first set of experiments is underway at the Sanford Underground Research Facility (SURF) in South Dakota. To date, stepwise stimulations have been performed at two locations, with the final stimulation connecting our injection and production wells. Numerous data have been collected and are currently being analyzed.

Enhanced Geothermal Systems, EGS Collab, Stimulati↗

The EGS Collab Hydroshear Experiment at the Sanford Underground Research Facility – Siting Criteria and Evaluation of Candidate Sites

The objective of the EGS Collab project is to establish a suite of intermediate-scale (~10-20 m) field test beds coupled with stimulation and interwell flow tests to provide a basis to better understand fracture stimulation methods, resulting fracture geometries, and processes that control heat transfer between rock and stimulated fractures. Experiment 1 of the project is being conducted at a depth of ~1.5 km in the Sanford Underground Research Facility (SURF) on the 4850 Level (ft. below the ground surface). The stimulation method planned for Experiment 2 of this project is hydroshearing of an existing natural fracture. In siting this experiment, there are several key geologic criteria that need to be met. These include: 1) the fracture should be least 10 m in length so that it could be intersected by two boreholes that are spaced that far apart; 2) it should be optimally oriented relevant to the stress field so that it is critically stressed; 3) the site should have appropriate stress conditions (not too shallow a depth); 4) the fracture should have sufficient permeability to allow for prestimulation flow testing, but not too high a permeability that would preclude permeability enhancement via shear stimulation; 5) the fracture should not intersect other features (permeable fractures, boreholes, adjacent drifts) that could serve as major leak-off zones; 6) the site should not be complicated by geology (a single lithology would be preferred). In addition, there are logistical criteria that will also influence site selection, including: 1) site availability/access, 2) logistical support, e.g., power, internet, water, operating rail system; 3) drift size and orientation compatible with drilling and site operations; 4) appropriate ground support. There are only two deep levels at SURF that can be accessed by the Yates Shaft: the 4100 and the 4850, so we limited our search to these two levels. Currently, three candidate sites are being evaluated: the existing Experiment 1 site and its surroundings on the West Drift on the 4850 level, and two locations on the 4100 level. This paper will evaluate advantages, disadvantages, and risks associated with these three options at SURF.

EGS Collab, Sanford Underground Research Facility↗

The EGS Collab Project: Stimulation and Simulation

Development of Enhanced Geothermal Systems (EGS) requires accurate predictions of flow rates and temperatures at production wells over time. The concept of EGS is simple; however, complications from heterogeneity and complexity of fracture pathways may lead to channeling, short-circuiting, and premature thermal breakthrough. In the EGS Collab project, we are establishing a suite of highly monitored and well characterized intermediate-scale (~10-20 m) field test beds along with fracture stimulation and interwell flow tests to better understand processes that control formation of effective subsurface heat exchangers. EGS Collab experiments will provide a means of testing tools and concepts that could later be employed under geothermal reservoir conditions at FORGE or elsewhere. Key to the project is using numerical simulations in the experiment design and interpretation of results. Our tests will be well-controlled, in situ experiments focused on rock fracture behavior and permeability enhancement. Our pre- and post-test modeling results of each field experiment compared with detailed measurements will allow for improved model prediction and validation. We will use comprehensive instrumentation to collect high-quality and high-resolution geophysical and other fracture characterization and fluid flow data. We will analyze these data and compare them with models and field observations to further elucidate the basic relationships between stress, induced seismicity, and permeability enhancement. We will also observe and quantify other key governing parameters that impact permeability, and will attempt to understand how these parameters might change throughout the development and operation of an EGS project with the ultimate goal of enabling commercial viability of EGS. Our first set of experiments will be performed at the Sanford Underground Research Facility (SURF) in South Dakota. Our team is well underway with building the first field experiment test bed planned for this project, which is supported by the US Department of Energy’s Geothermal Technologies Office.

EGS Collab↗

An Overview of the EGS Collab Project: Field Validation of Coupled Process Modeling of Fracturing and Fluid Flow at the Sanford Underground Research Facility, Lead, SD

Enhanced Geothermal Systems (EGS) development will require an ability to accurately predict the flow rates and temperatures of the production wells. While simple in concept, complex heterogeneous fracture pathways can lead to channeling, short-circuiting, and premature thermal breakthrough complicating EGS. The EGS Collab project will establish a suite of intermediate-scale (~10-20 m) field test beds coupled with stimulation and interwell flow tests to provide a basis to better understand the fracture geometries and processes that control heat transfer between rock and stimulated fractures. These experiments will provide a means of testing tools, codes, and concepts that could later be employed under geothermal reservoir conditions at FORGE and in EGS. We will perform well-controlled, in situ experiments focused on rock fracture behavior and permeability enhancement. Pre- and post-test modeling of each test will allow for model prediction and validation. Comprehensive instrumentation will be used to collect high-quality, high-resolution geophysical and fracture characterization and fluid flow data. ,These data will be analyzed and compared with models and field observations to further elucidate the basic relationships between stress, induced seismicity, and permeability enhancement. To the maximum extent achievable, we will observe and quantify other key governing parameters that impact permeability, and attempt to understand how these parameters might change throughout the development and operation of an EGS project with the goal of enabling commercial viability of EGS. The Sanford Underground Research Facility (SURF) in South Dakota was selected as the EGS Collab project experimental site based on the evaluation of information from several sites. Our team has designed and constructed the first field experiment planned for this project, which is supported by the US Department of Energy’s Geothermal Technologies Office.

EGS, FORGE, field fracture stimulation and flow ex↗

Fracture and Flow Designs for the Collab/SIGMA-V Project

The first experiment of the Enhanced Geothermal Systems (EGS) Collab (a.k.a Stimulation Investigations for Geothermal Modeling Analysis and Validation (SIGMA-V)) project is designed to comprehensively monitor a series of hydraulic fracture stimulations and subsequent flow tests. This experiment is planned for the 4850 Level in the Sanford Underground Research Facility (SURF), located at the former Homestake Gold Mine, in Lead, South Dakota. The target host rock for these stimulations and flow tests is a phyllite schist known as the Poorman formation. This paper discusses at a high level the engineering design for the stimulation and fracture monitoring system, the considerations for the test bed construction, and the preliminary stimulation modeling. Furthermore, this paper will highlight the intricate ways that predictive modeling can be used for testbed and stimulation design. This project is funded by the United States Department of Energy, Geothermal Technologies Office (GTO).

Knox, Hunter↗

A robust return-map algorithm for general multisurface plasticity

Three new contributions to the field of multisurface plasticity are presented for general situations with an arbitrary number of nonlinear yield surfaces with hardening or softening. A method for handling linearly dependent flow directions is described. A residual that can be used in a line search is defined. An algorithm that has been implemented and comprehensively tested is discussed in detail. Examples are presented to illustrate the computational cost of various components of the algorithm. The overall result is that a single Newton-Raphson iteration of the algorithm costs between 1.5 and 2 times that of an elastic calculation. Examples also illustrate the successful convergence of the algorithm in complicated situations. For example, without using the new contributions presented here, the algorithm fails to converge for approximately 50% of the trial stresses for a common geomechanical model of sedementary rocks, while the current algorithm results in complete success. Since it involves no approximations, the algorithm is used to quantify the accuracy of an efficient, pragmatic, but approximate, algorithm used for sedimentary-rock plasticity in a commercial software package. Furthermore, the main weakness of the algorithm is identified as the difficulty of correctly choosing the set of initially active constraints in the general setting.

15 GEOTHERMAL ENERGY↗