Impact of Thermal Loading on Waste Package Material Performance

AbstractThis report focuses on the prediction of materials performance for the carbon steel corrosion-allowance container as a function of thermal loading for the potential repository at Yucca Mountain. Low, intermediate and high thermal loads were evaluated as to their performance given assumptions regarding the temperature and humidity changes with time and the resultant depth of corrosion penetration. The reference case involved a kinetic relation for corrosion that was utilized in a sensitivity analysis to examine the impacts of time exponent, pitting, and microbiologically-influenced corrosion. As a result of this study, the high thermal load appears to offer the best corrosion performance. However, other factors must be considered in making the final thermal loading decision.

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Localized Dryout: an Approach for Managing the Thermal-Hydrological Effects of Decay Heat at Yucca Mountain

MRS Proceedings ◽

10.1557/proc-412-715 ◽

1995 ◽

Vol 412 ◽

Cited By ~ 7

Author(s):

Thomas A. Buscheck ◽

John J. Nitao ◽

Lawrence D. Ramspot

Keyword(s):

Relative Humidity ◽

Thermal Load ◽

Large Scale ◽

Thermal Loading ◽

Yucca Mountain ◽

Large Temperature ◽

Nuclear Waste Repository ◽

Waste Package ◽

Decay Heat ◽

Hydrological Effects

AbstractFor a nuclear waste repository in the unsaturated zone at Yucca Mountain, there are two thermal loading approaches to using decay heat constructively-that is, to substantially reduce relative humidity and liquid flow near waste packages for a considerable time, and thereby limit waste package degradation and radionuclide dissolution and release. “Extended dryout” achieves these effects with a thermal load high enough to generate large-scale (coalesced) rock dryout. “Localized dryout”(which uses wide drift spacing and a thermal load too low for coalesced dryout) achieves them by maintaining a large temperature difference between the waste package and drift wail; this is done with close waste package spacing (generating a high line-heat load) and/or low-thermal-conductivity backfill in the drift. Backfill can greatly reduce relative humidity on the waste package in both the localized and extended dryout approaches. Besides using decay heat constructively, localized dryout reduces the possibility that far-field temperature rise and condensate buildup above the drifts might adversely affect waste isolation.

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The Importance of Thermal Loading Conditions to Waste Package Performance at Yucca Mountain

MRS Proceedings ◽

10.1557/proc-353-403 ◽

1994 ◽

Vol 353 ◽

Author(s):

Thomas A. Buscheck ◽

John J. Nitao

Keyword(s):

Relative Humidity ◽

Thermal Load ◽

Thermal Loading ◽

Yucca Mountain ◽

Thermal Loads ◽

Ambient Conditions ◽

Factors Affecting ◽

Waste Package ◽

Load Distributions ◽

Wide Range

AbstractTemperature and relative humidity are primary environmental factors affecting waste package corrosion rates for the potential repository in the unsaturated zone at Yucca Mountain, Nevada. Under ambient conditions, the repository environment is quite humid. If relative humidity is low enough (<70%), corrosion will be minimal. Under humid conditions, corrosion is reduced if the temperature is low (<60°C). Using the V-TOUGH code, we model thermo-hydrological flow to investigate the effect of repository heat on temperature and relative humidity in the repository for a wide range of thermal loads. These calculations indicate that repository heat may substantially reduce relative humidity on the waste package, over hundreds of years for low thermal loads and over tens of thousands of years for high thermal loads. Temperatures associated with a given relative humidity decrease with increasing thermal load. Thermal load distributions can be optimized to yield a more uniform reduction in relative humidity during the boiling period.

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Microbiologically Influenced Corrosion Capability of Bacteria Isolated from Yucca Mountain

CORROSION ◽

10.5006/1.3299233 ◽

2004 ◽

Vol 60 (1) ◽

pp. 64-74 ◽

Cited By ~ 21

Author(s):

B. J. Pitonzo ◽

P. Castro ◽

P. S. Amy ◽

G. Southam ◽

D. A. Jones ◽

...

Keyword(s):

Yucca Mountain ◽

Microbiologically Influenced Corrosion

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INFLUENCE OF GRAM-NEGATIVE STRAIN KLEBSIELLA OXYTOCA ON BIOCORROSION

Asian Journal of Pharmaceutical and Clinical Research ◽

10.22159/ajpcr.2018.v11i2.19431 ◽

2018 ◽

Vol 11 (2) ◽

pp. 67

Author(s):

Chitra S ◽

Anand B

Keyword(s):

Electrochemical Impedance ◽

Klebsiella Oxytoca ◽

Steel Corrosion ◽

Microbiologically Influenced Corrosion ◽

Extracellular Polysaccharides ◽

Morphological Examination ◽

Industry Standard ◽

Mild Steel Corrosion ◽

Toxic Drugs ◽

Enormous Number

Several studies of biofilms must accept that biofilms may develop in an enormous number of environments. This biofilm forms colonization on the solid surfaces by extracellular polysaccharides (EPSs) secreted by the microbial cells. The EPSs secreted by microbial cell stimulate corrosion in the engineered materials due to the presence of polyanionic neutral macromolecules. Many techniques have been described measuring and inhibiting microbiologically influenced corrosion; however, none has been accepted as an industry standard. This is because the risks posed to the marine biosphere due to the use of antifouling inhibitors. Recently, a large amount of literature has been edited on the influence of toxic biocides on non-targeted organisms in the marine environment are most likely. It has been shown that the modifications of antifouling inhibitors by the non-toxic drugs can reduce microbial adhesion and some disentangle effects toward the environment. Hence, in this paper, the inhibition effect of neomycin trisulfate on the Klebsiella oxytoca on mild steel corrosion has been investigated using weight loss measurement, electrochemical impedance spectroscopy, Fourier-transform infrared, and scanning electron microscopy (SEM). These studies have shown that neomycin trisulfate shows better inhibition toward the microbe. The agreement with the experimental data was also found to be satisfactory. Further, surface morphological examination through SEM confirms that the inhibitor inhibits the microbes by blocking the EPS

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Effects of Upstream Step Geometry on Axisymmetric Converging Vane Endwall Secondary Flow and Heat Transfer at Transonic Conditions

Journal of Turbomachinery ◽

10.1115/1.4041294 ◽

2018 ◽

Vol 140 (12) ◽

Cited By ~ 2

Author(s):

Zhigang Li ◽

Luxuan Liu ◽

Jun Li ◽

Ridge A. Sibold ◽

Wing F. Ng ◽

...

Keyword(s):

Heat Transfer ◽

Secondary Flow ◽

Thermal Load ◽

Numerical Study ◽

Guide Vane ◽

Leading Edge ◽

Step Height ◽

Temperature History ◽

Flow And Heat Transfer ◽

High Thermal Load

This paper presents a detailed experimental and numerical study on the effects of upstream step geometry on the endwall secondary flow and heat transfer in a transonic linear turbine vane passage with axisymmetric converging endwalls. The upstream step geometry represents the misalignment between the combustor exit and the nozzle guide vane endwall. The experimental measurements were performed in a blowdown wind tunnel with an exit Mach number of 0.85 and an exit Re of 1.5×106. A high freestream turbulence level of 16% was set at the inlet, which represents the typical turbulence conditions in a gas turbine engine. Two upstream step geometries were tested for the same vane profile: a baseline configuration with a gap located 0.88Cx (43.8 mm) upstream of the vane leading edge (upstream step height = 0 mm) and a misaligned configuration with a backward-facing step located just before the gap at 0.88Cx (43.8 mm) upstream of the vane leading edge (step height = 4.45% span). The endwall temperature history was measured using transient infrared thermography, from which the endwall thermal load distribution, namely, Nusselt number, was derived. This paper also presents a comparison with computational fluid dynamics (CFD) predictions performed by solving the steady-state Reynolds-averaged Navier–Stokes with Reynolds stress model using the commercial CFD solver ansysfluent v.15. The CFD simulations were conducted at a range of different upstream step geometries: three forward-facing (upstream step geometries with step heights from −5.25% to 0% span), and five backward-facing, upstream step geometries (step heights from 0% to 6.56% span). These CFD results were used to highlight the link between heat transfer patterns and the secondary flow structures and explain the effects of upstream step geometry. Experimental and numerical results indicate that the backward-facing upstream step geometry will significantly enlarge the high thermal load region and result in an obvious increase (up to 140%) in the heat transfer coefficient (HTC) level, especially for arched regions around the vane leading edge. However, the forward-facing upstream geometry will modestly shrink the high thermal load region and reduce the HTC (by ∼10% to 40% decrease), especially for the suction side regions near the vane leading edge. The aerodynamic loss appears to have a slight increase (0.3–1.3%) because of the forward-facing upstream step geometry but is slightly reduced (by 0.1–0.3%) by the presence of the backward upstream step geometry.

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The Influence of Repository Thermal Load on Multiphase Flow and Heat Transfer in the Unsaturated Zone of Yucca Mountain

10.2172/840144 ◽

2005 ◽

Author(s):

Yu-Shu Wu ◽

S. Mukhopadhyay ◽

K. Zhang ◽

G.S. Bodvarsson

Keyword(s):

Heat Transfer ◽

Multiphase Flow ◽

Unsaturated Zone ◽

Thermal Load ◽

Yucca Mountain ◽

Flow And Heat Transfer

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Studies of Altered Vitrophyre for the Prediction of Nuclear waste Repository-Induced Thermal Alteration at Yucca Mountain, Nevada

MRS Proceedings ◽

10.1557/proc-26-959 ◽

1983 ◽

Vol 26 ◽

Author(s):

Schon S. Levy

Keyword(s):

Nuclear Waste ◽

Thermal Loading ◽

Adsorbed Water ◽

Yucca Mountain ◽

Nuclear Waste Repository ◽

Thermal Alteration ◽

Secondary Porosity ◽

Hydrous Minerals ◽

Waste Repository ◽

A Minor

ABSTRACTNuclear waste emplacement in devitrified volcanic tuff at Yucca Mountain will raise the temperature of surrounding rock for a geologically significant period of time. This study evaluates the susceptibility of an underlying 50 ft-thick vitrophyre to thermal alteration by examining alteration that occurred in the rock as it cooled after deposition. A 10°C temperature rise should have no mineralogical effects on the vitrophyre, but an increase of 60° or more is likely to result in alteration. Expected mineralogic changes in the vitrophyre caused by this amount of thermal loading include crystallization of zeolites and smectite. Alteration will be concentrated in a thin interval near the top of the vitrophyre and along fractures. Adsorbed water and water in preexisting hydrous minerals and in glass may contribute to hydrothermal alteration of underlying vitrophyre. Bulk porosity change would be slight and local porosity increase would probably be restricted to the upper part of the vitrophyre. Although some fracture filling could occur, such a minor sealing effect would be balanced by development of secondary porosity. Zeolites and smectite, newly-crystallized along fluid flow paths below the waste repository, could provide an enhanced sorptive barrier to radionuclide migration.

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Numerical Analysis of Effect of Cyclic Thermal Load on Concrete to Concrete Bonding

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.722.18 ◽

2016 ◽

Vol 722 ◽

pp. 18-26 ◽

Cited By ~ 1

Author(s):

Yuliia Khmurovska ◽

Petr Štemberk ◽

Martin Petřík ◽

Ippei Maruyama ◽

Ondřej Holčapek

Keyword(s):

Experimental Investigation ◽

Thermal Load ◽

Thermal Loading ◽

Concrete Structures ◽

High Quality ◽

Bonding Quality ◽

Critical Stresses ◽

First Results ◽

Adhesive Materials

This paper presents a numerical simulation and preliminary experimental investigation of bonding of concrete structures using cement and polymer cement as adhesive materials. The numerical model of concrete plates bonded with the polymer cement is created and subjected to cyclic thermal loading. As a result, the critical stresses are obtained. Also all the necessary materials for carrying out high-quality, fast and inexpensive experimental investigation of the strength of cement and polymer cement bond are prepared. The experimental setup and the first results obtained are also described. The bonding quality of the polymer cement shows satisfactory results under this kind of loading, thus the use of the polymer cement for bonding of concrete structures of different properties is reasonable in the specific fields considered in this study.

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