Multi-Scale Near-Field Thermohydrologic Analysis of Alternative Designs for the Potential Repository at Yucca Mountain

1999 ◽  
Vol 556 ◽  
Author(s):  
T. A. Buscheck ◽  
J. Gansemer ◽  
J. J. Nitao ◽  
T. H. Delorenzo
Keyword(s):  
Near Field ◽  
High Heat ◽  
Yucca Mountain ◽  
Point Load ◽  
Scale Model ◽  
Heat Output ◽  
Total System ◽  
Line Load ◽  
Multi Scale ◽  
License Application

AbstractA multi-scale, thermohydrologic (TH) modeling methodology has been developed that integrates the results from 1-, 2-, and 3-D drift-scale models and a 3-D mountain-scale model to calculate the near-field TH variables affecting the performance of the engineered barrier system (EBS) of the potential repository at Yucca Mountain. This information was used by Total System Performance Assessment—Viability Assessment (TSPA-VA) and is being used by the ongoing TSPA, supporting the License Application Design Selection, to assess waste-package (WP) corrosion, waste-form dissolution, and radionuclide transport in the EBS. Line-load WP spacing, which places WPs nearly end to end in widely spaced drifts, results in more locally intensive and uniform heating along drifts, causing hotter, drier, and more uniform conditions on WPs than point-load spacing, which is used in the VA design. Backfilling drifts with a granular material with coarse, well-sorted, nonporous grains (e.g., a coarse quartz sand) results in a large, persistent reduction in RH on WPs; point-load spacing allows only the medium-to-high-heat-output WPs to benefit from RH reduction, but line-load spacing enables all WPs to benefit.

scholarly journals Near-Field Thermal-Hydrological Behavior for Alternative Repository Designs at Yucca Mountain

1996 ◽  
Vol 465 ◽  
Author(s):  
Thomas A. Buscheck ◽  
John J. Nitao ◽  
Lawrence D. Ramspott
Keyword(s):  
Liquid Phase ◽  
Relative Humidity ◽  
Near Field ◽  
Three Dimensional ◽  
Yucca Mountain ◽  
Point Load ◽  
High Level Waste ◽  
Line Load ◽  
Large Variability ◽  
High Level

ABSTRACTThree-dimensional calculations that explicitly represent a realistic mixture of waste packages (WPs) are used to analyze decay-heat-driven thermal-hydrological behavior around emplacement drifts in a potential high-level waste facility at Yucca Mountain. Calculations, using the NUFT code, compare two fundamentally different ways that WPs can be arranged in the repository, with a focus on temperature, relative humidity, and liquid-phase flux on WPs. These quantities strongly affect WP integrity and the mobilization and release of radionuclides from WPs. Point-load spacing, which places the WPs roughly equidistant from each other, thermally isolates WPs from each other, causing large variability in temperature, relative humidity, and liquid-phase flux along the drifts. Line-load spacing, which places WPs nearly end to end in widely spaced drifts, results in more locally intensive and uniform heating along the drifts, causing hotter, drier, and more uniform conditions. A larger and more persistent reduction in relative humidity on WPs occurs if the drifts are backfilled with a low-thermal-conductivity granular material with hydrologie properties that minimize moisture wicking.

Accounting For Corrosion Of Hlw Glasses By Humid Air In TSPA

2002 ◽  
Vol 757 ◽  
Author(s):  
W. L. Ebert ◽  
J. C. Cunnane ◽  
N. L. Dietz
Keyword(s):  
Rate Equation ◽  
Ph Dependence ◽  
Yucca Mountain ◽  
Total System ◽  
Humid Air ◽  
Determine Parameter ◽  
Glass Dissolution ◽  
A Value ◽  
License Application ◽  
Parameter Values

ABSTRACTThis paper describes how the results of vapor hydration tests (VHTs) are used to model the corrosion of waste glasses exposed to humid air in the glass degradation model for total system performance assessment (TSPA) calculations for the proposed Yucca Mountain disposal system. Corrosion rates measured in VHTs conducted at 125, 150, 175, and 200°C are compared with the rate equation for aqueous dissolution to determine parameter values that are applicable to glass degradation in humid air. These will be used to determine the minimum for the range and distribution of parameter values in calculations for the Yucca Mountain disposal system license application (TSPA-LA). The rate equation for glass dissolution is rate = kE • 10 η • pH • exp(–Ea/RT). Uncertainties in the calculated rate due to the range of waste glass compositions and water exposure conditions are taken into account by using a range of values for the rate coefficient kE. The parameter values for the pH dependence (η) and temperature dependence (Ea) and the upper limit for kE are being determined with other tests. Using the values of η and Ea from the site recommendation model, the VHT results described in this paper provide a value of log kE = 5.1 as the minimum value for the rate expression. This value will change slightly if different pH-and temperature-dependencies are used for the TSPA-LA model.

Proceeding Toward a License Application for U.S. Nuclear Waste Repository: Total System Performance Assessment Approach

2003 ◽  
Author(s):  
Jerry McNeish ◽  
Peter Swift ◽  
Rob Howard ◽  
David Sevougian ◽  
Donald Kalinich ◽  
...  
Keyword(s):  
Performance Assessment ◽  
System Performance ◽  
Nuclear Regulatory Commission ◽  
The United States ◽  
Yucca Mountain ◽  
Nuclear Waste Repository ◽  
Total System ◽  
License Application ◽  
Regulatory Commission ◽  
The U.S

The development of a deep geologic repository system in the United States has progressed to the preparation of an application for a license from the U.S. Nuclear Regulatory Commission. The project received site recommendation approval from the U.S. President in early 2002. The next phase of the project involves development of the license application (LA) utilizing the vast body of information accumulated in study of the site at Yucca Mountain, Nevada. Development of the license application involves analyses of the total system performance assessment (TSPA) of the repository, the TSPA-LA. The TSPA includes the available relevant information and model analyses from the various components of the system (e.g., unsaturated geologic zone, engineered system (waste packaging and drift design), and saturated geologic zone) (see Fig. 1 for nominal condition components), and unites that information into a single computer model used for evaluating the potential future performance or degradation of the repository system. The primary regulatory guidance for the repository system is found in 10 CFR 63, which indicates the acceptable risk to future populations from the repository system. The performance analysis must be traceable and transparent, with a defensible basis. The TSPA-LA is being developed utilizing state-of-the-art modeling software and visualization techniques, building on a decade of experience with such analyses. The documentation of the model and the analyses will be developed with transparency and traceability concepts to provide an integrated package for reviewers. The analysis relies on 1000’s of pages of supporting information, and multiple software and process model analyses. The computational environment represents the significant advances in the last 10 years in computer workstations. The overall approach will provide a thorough, transparent compliance analysis for consideration by the U.S. Nuclear Regulatory Commission in evaluating the Yucca Mountain repository.

Lessons Learned from the Yucca Mountain and WIPP Projects

2010 ◽  
Vol 73 ◽  
pp. 194-202 ◽  
Author(s):  
Evaristo J. Bonano ◽  
David S. Kessel ◽  
Lori J. Dotson
Keyword(s):  
System Analysis ◽  
The United States ◽  
Yucca Mountain ◽  
Lessons Learned ◽  
Total System ◽  
Waste Isolation Pilot Plant ◽  
License Application ◽  
Long Term Performance ◽  
Term Performance

For more than 30 years Sandia National Laboratories (SNL) has played a key role in the development and implementation of total system analyses of waste management systems in the United States. Two very important applications have been the total system analysis of long term performance that supported (1) the Compliance Certification Application (CCA) for the Waste Isolation Pilot Plant (WIPP) in 1996 and (2) the License Application (LA) for the Yucca Mountain (YM) Repository in 2008.

scholarly journals The Multi-Scale Model Approach to Thermohydrology at Yucca Mountain

2002 ◽  
Author(s):  
L Glascoe ◽  
T A Buscheck ◽  
J Gansemer ◽  
Y Sun
Keyword(s):  
Yucca Mountain ◽  
Scale Model ◽  
Multi Scale ◽  
Model Approach

Three-dimensional Reconstruction of Microscopic Image Based on Multi-ST Algorithm

2020 ◽  
Vol 64 (2) ◽  
pp. 20506-1-20506-7
Author(s):  
Min Zhu ◽  
Rongfu Zhang ◽  
Pei Ma ◽  
Xuedian Zhang ◽  
Qi Guo
Keyword(s):  
3D Reconstruction ◽  
Three Dimensional ◽  
Scale Model ◽  
Microscopic Image ◽  
Multi Scale ◽  
Gaussian Pyramid ◽  
Cost Aggregation ◽  
Dimensional Reconstruction ◽  
Image Pairs ◽  
Accurate Matching

Abstract Three-dimensional (3D) reconstruction is extensively used in microscopic applications. Reducing excessive error points and achieving accurate matching of weak texture regions have been the classical challenges for 3D microscopic vision. A Multi-ST algorithm was proposed to improve matching accuracy. The process is performed in two main stages: scaled microscopic images and regularized cost aggregation. First, microscopic image pairs with different scales were extracted according to the Gaussian pyramid criterion. Second, a novel cost aggregation approach based on the regularized multi-scale model was implemented into all scales to obtain the final cost. To evaluate the performances of the proposed Multi-ST algorithm and compare different algorithms, seven groups of images from the Middlebury dataset and four groups of experimental images obtained by a binocular microscopic system were analyzed. Disparity maps and reconstruction maps generated by the proposed approach contained more information and fewer outliers or artifacts. Furthermore, 3D reconstruction of the plug gauges using the Multi-ST algorithm showed that the error was less than 0.025 mm.

Effects of parametric uncertainty on multi-scale model predictions of shock response of a pressed energetic material

2019 ◽  
Vol 125 (23) ◽  
pp. 235104 ◽  
Author(s):  
Sangyup Lee ◽  
Oishik Sen ◽  
Nirmal Kumar Rai ◽  
Nicholas J. Gaul ◽  
K. K. Choi ◽  
...  
Keyword(s):  
Energetic Material ◽  
Parametric Uncertainty ◽  
Scale Model ◽  
Multi Scale ◽  
Model Predictions ◽  
Shock Response

scholarly journals The Winter Habitat Selection of Red Deer (Cervus elaphus) Based on a Multi-Scale Model

Animals ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 2454
Author(s):  
Yue Sun ◽  
Yanze Yu ◽  
Jinhao Guo ◽  
Minghai Zhang
Keyword(s):  
Habitat Selection ◽  
Environmental Factors ◽  
Cervus Elaphus ◽  
Red Deer ◽  
Scale Model ◽  
Winter Habitat ◽  
Multi Scale ◽  
Optimal Scale ◽  
Scale Models ◽  
Selection Of

Single-scale frameworks are often used to analyze the habitat selections of species. Research on habitat selection can be significantly improved using multi-scale models that enable greater in-depth analyses of the scale dependence between species and specific environmental factors. In this study, the winter habitat selection of red deer in the Gogostaihanwula Nature Reserve, Inner Mongolia, was studied using a multi-scale model. Each selected covariate was included in multi-scale models at their “characteristic scale”, and we used an all subsets approach and model selection framework to assess habitat selection. The results showed that: (1) Univariate logistic regression analysis showed that the response scale of red deer to environmental factors was different among different covariate. The optimal scale of the single covariate was 800–3200 m, slope (SLP), altitude (ELE), and ratio of deciduous broad-leaved forests were 800 m in large scale, except that the farmland ratio was 200 m in fine scale. The optimal scale of road density and grassland ratio is both 1600 m, and the optimal scale of net forest production capacity is 3200 m; (2) distance to forest edges, distance to cement roads, distance to villages, altitude, distance to all road, and slope of the region were the most important factors affecting winter habitat selection. The outcomes of this study indicate that future studies on the effectiveness of habitat selections will benefit from multi-scale models. In addition to increasing interpretive and predictive capabilities, multi-scale habitat selection models enhance our understanding of how species respond to their environments and contribute to the formulation of effective conservation and management strategies for ungulata.

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