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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 19 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2017

Material Investigation and Long-term Sealing Behavior of Helicoflex{sup R} Metal Seals used in Containers for Spent Nuclear Fuel - 17135

In Germany spent nuclear fuel is stored and transported in casks that possess bolted lid systems equipped with double jacket metal seals of Helicoflex{sup R} type in order to enable safe enclosure of the radioactive inventory. A dry interim storage period of 40 years was planned and the casks are licensed for that time span. However, due to political reasons and delayed disposal projects this time span is expected to increase significantly. It is therefore necessary to evaluate the long-term sealing behavior of the casks exceeding 40 years of operating time. In this paper, we discuss our approach to investigate the aging behavior of such metal seals, and to predict the long-term sealing behavior. Accelerated aging component tests with seals are performed at temperatures up to 150 deg. C to investigate the course of seal force, usable resilience and leakage rate. Even though these tests have already shown a significant decrease in seal force and usable resilience after aging times of less than 1 year, for most seals the leakage rate stayed better than the specified value. However, observation of the leakage rate has to be continued to determine the aging effect on the seal properties. As a main influence on the seal long-term behavior the increasing permanent deformation of the outer jacket has been recognized. It is made of aluminum or silver which means that the temperatures that are relevant for the aforementioned application in casks lead to creep deformation. For further investigation of seal behavior a comprehensive research program concerning the material characteristics and aging behavior of the individual seal components, with an emphasis on the outer jacket material, has been launched. The aim is to get a better understanding of the time and temperature dependent creep mechanisms and deformation. The examinations are separated into tests on seal segments and tests on standardized specimen. In order to be able to study the aging process, seal segments are compressed in flanges and stored at temperatures ranging from room temperature to 150 deg. C. After defined time intervals the segments are analyzed by using standardized tests including structure investigation and creep tests. The results are compared with the behavior of the specimen basic raw material. This is done to ensure comparability of the thin jacket material and additional sheet material used for standardized tests. Thus, the prediction of component changes after different aging times at different temperatures can be made. As a result forecasts on the long term seal behavior are intended. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2020

Mechanical seal with high pressure high temperature secondary seal

A secondary seal of a mechanical seal comprises an annular sealing gasket and backing plate surrounding a cylindrical sealing surface, all of which can be made of the same metallic material. The gasket is C-shaped in cross section, and is axially pressed during operation into a C-shaped groove formed in the backing plate, the groove being shallower and larger in inner diameter than the gasket, so that the gasket, when pressed into the groove, deforms radially inward and seals against both the backing plate and the sealing surface. The contact area between the gasket and sealing surface increases with pressure. In embodiments, when the pressure is released, the gasket retracts from the sealing surface, allowing easy disassembly and allowing axial movement of the gasket and backing plate. Highly polished surfaces of the gasket and sealing surface can allow axial motion thereof during operation to maintain the seal face gap.

42 ENGINEERING↗
DOE OSTI2015

Outcomes of the full scale seal experiment: a seal industrial prototype for the Cigeo project - 15207

The Full Scale Seal (FSS) Experiment is one of various experiments implemented by Andra, within the frame of the French HLW and IL-LLW Deep Geological Repository Project (aka Cigeo) development, to demonstrate the technical feasibility and check the performance of the seals which will be constructed in the shafts, ramps, drifts and disposal vaults, at time of Cigeo underground facilities progressive closure. The FSS experimental objectives, principles and rationale were presented at WM'2013 (Paper 1306): FSS is a technological demonstrator built on surface, inside a concrete made horizontal drift model (also called the 'test box'). FSS is part of the European DOPAS (Demonstration of Plugs and Seals) [2] project, under the umbrella of the Implementing Geological Disposal - Technology Platform (IGD-TP) [3] project. FSS construction activities started in July 2012 and were completed in September 2014. The construction compliance assessment work activities are now ongoing (and will be continued until mid-2015). This paper presents the construction and monitoring story of the FSS components, starting with the construction of a first containment wall based on a low pH self-compacting concrete (SCC), followed by the swelling clay core backfilling sequence and finishing with the erection of a second containment wall based on a low pH shotcrete. The FSS experiment also enabled to qualify the commissioning methods applicable to an industrial sealing work at time of underground operations in the Repository. These commissioning methods are described and the results discussed. The equipment and methods used for the purpose of seal component construction and monitoring are presented. The physical characteristics obtained for each component of the seal are detailed and the compliance of measured values with the initial requirements is commented. The post-mortem work planned (e.g. coring and wire sawing of low pH concrete containment walls, use of penetrometer for the swelling clay core...) is also explained. FSS is a first of a kind experiment, by its size, by the technical choices made. The first technical outcomes were presented to the French Nuclear Authority and to its Technical Support Organization. The successful implementation of the work carried out in the FSS drift model was positively assessed by the evaluators and deemed representative of the real underground conditions (industrial feasibility is proven). This article concludes with a critical analysis of the methods and equipment used, of the results obtained and provides some perspectives of improvement for the construction of the first Cigeo industrial prototype seals scheduled around 2030 in ramps and horizontal drifts (provided the Cigeo construction is authorized in late 2020, and following the licensing request filing scheduled in late 2017). (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2016

Sealing device for providing a seal in a turbomachine

Sealing device for providing seals between adjacent components, and turbomachines utilizing such sealing devices, are provided. A sealing device includes a seal plate insertable between the adjacent components, the seal plate comprising a first face and an opposing second face. The sealing device further includes a plurality of pins extending from one of the first face or the second face, the plurality of pins configured to space the one of the first face or the second face from contact surfaces of the adjacent components.

42 ENGINEERING↗
DOE OSTI2014

Method of sealing a bipolar plate supported solid oxide fuel cell with a sealed anode compartment

Methods of sealing a bipolar plate supported solid oxide fuel cell with a sealed anode compartment are provided. The solid oxide fuel cell includes a cathode, an electrolyte, and an anode, which are supported on a metallic bipolar plate assembly including gas flow fields and the gas impermeable bipolar plate. The electrolyte and anode are sealed into an anode compartment with a metal perimeter seal. An improved method of sealing is provided by extending the metal seal around the entire perimeter of the cell between an electrolyte and the bipolar plate to form the anode compartment. During a single-step high temperature sintering process the metal seal bonds to the edges of the electrolyte and anode layers, the metal foam flow field and the bipolar plate to form a gastight containment.

25 ENERGY STORAGE↗
DOE OSTI2013

The Full Scale Seal Experiment - A Seal Industrial Prototype for Cigeo - 13106

The Full Scale Seal (FSS) Experiment is one of various experiments implemented by Andra, within the frame of the Cigeo (the French Deep Geological Repository) Project development, to demonstrate the technical construction feasibility and performance of seals to be constructed, at time of Repository components (shafts, ramps, drifts, disposal vaults) progressive closure. FSS is built inside a drift model fabricated on surface for the purpose. Prior to the scale 1:1 seal construction test, various design tasks are scheduled. They include the engineering work on the drift model to make it fit with the experimental needs, on the various work sequences anticipated for the swelling clay core emplacement and the concrete containment plugs construction, on the specialized handling tools (and installation equipment) manufactured and delivered for the purpose, and of course on the various swelling clay materials and low pH (below 11) concrete formulations developed for the application. The engineering of the 'seal-as-built' commissioning means (tools and methodology) must also be dealt with. The FSS construction experiment is a technological demonstrator, thus it is not focused on the phenomenological survey (and by consequence, on the performance and behaviour forecast). As such, no hydration (forced or natural) is planned. However, the FSS implementation (in particular via the construction and commissioning activities carried out) is a key milestone in view of comforting phenomenological extrapolation in time and scale. The FSS experiment also allows for qualifying the commissioning methods of a real sealing system in the Repository, as built, at time of industrial operations. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2017

Sealing glass-ceramics with near-linear thermal strain, part III: Stress modeling of strain and strain rate matched glass-ceramic to metal seals

Thermal mechanical stresses of glass-ceramic to stainless steel (GCtSS) seals are analyzed using finite element modeling over a temperature cycle from a set temperature (T set ) 500°C to -55°C, and then back to 600°C. There are two glass-ceramics that have an identical coefficient of thermal expansion (CTE) at ~16 ppm/°C but have very different linearity of thermal strains, designated as near-linear NL16 and step-like SL16, and were formed from the same parent glass using different crystallization processes. Stress modeling reveals much higher plastic strain in the stainless steel using SL16 glass-ceramic when the GCtSS seal cools from T set . Upon heating tensile stresses start to develop at the GC-SS interface before the temperature reaches T set . On the other hand, the much lower plastic deformation in stainless steel accumulated during cooling using NL16 glass-ceramic allows for radially compressive stress at the GC-SS interface to remain present when the seal is heated back to T set . Finally, the qualitative stress comparison suggests that with a better match of thermal strain rate to that of stainless steel, the NL16 glass-ceramic not only improves the hermeticity of the GCtSS seals, but would also improve the reliability of the seals exposed to high-temperature and/or high-pressure abnormal environments.

36 MATERIALS SCIENCE↗
DOE OSTI2023

User’s Manual for Seal_Flux: A Seal Barrier Reduced-Order Model (Update)

This report provides a brief description on the use of the Seal_Flux computer program developed as part of the effort to quantify the risk of geologic storage of carbon dioxide (CO 2 ) under the U.S. Department of Energy’s (DOE) National Risk Assessment Partnership (NRAP). The Seal_Flux code simulates the flow of CO 2 through a low permeability rock horizon or seal formation overlying the storage reservoir into which CO 2 is injected. A two-phase, relative permeability approach with Darcy’s law is used for one-dimensional (1D) flow computations of CO 2 through the horizon in the vertical direction. The code also allows the simulation of time-dependent processes that can influence such flow. However, as part of its design, Seal_Flux is what can be termed a “reduced-order model” (ROM) and is not intended as a full-functioning flow code. The theory and simulation in the code is streamlined and directed towards the implementation of Monte Carlo risk analyses of CO 2 transport or as termed in this context as “leakage.” While presented in this report as a stand-alone tool, the Seal_Flux code is intended to function in the future as one of several models as part of an integrated, systems-level model of CO 2 storage performance. Finally, the code is written in Python 3.10 to provide an open framework for further development by others and to assist in linking the code with other modules in an integrated assessment model.

58 GEOSCIENCES↗
DOE OSTI2016

The Enhanced Sealing Project, Monitoring a Full-Scale Shaft Seal at Canada's Underground Research Laboratory (2009-2015) - 16070

A full-scale shaft seal was designed and installed in the 5-m-diameter main shaft at Canada's Underground Research Laboratory (URL) in 2009. Located where the main shaft intersects a water-bearing fracture zone at a depth of approximately 273 m, a 6-m-thick clay component was sandwiched between two 3-m-thick concrete components. The clay component was 40:60 mixture of bentonite and quartz/feldspar sand and spans approximately 1 m beyond the maximum identified vertical extent of the fracture zone. Its purpose is to limit the mixing of saline groundwater from the deeper region with the fresher, near-surface groundwater. Its construction was part of Canada's Nuclear Legacy Liabilities Program (NLLP). The 1. phase of the Enhanced Sealing Project (ESP), a jointly-funded Research, Development and Demonstration (RD and D) project was started in 2009 to monitor the saturation of the shaft seal until the end of 2013. The 2. phase, extended monitoring of the ESP is supported by Posiva (Finland), Andra (France) and CNL (Canada) and this will run until the end of 2016. The slow evolution of the seal and its surroundings and complete removal of the surface facilities at the URL site in 2014, has meant that the ESP monitoring has evolved to a stand-alone, lower frequency data collection program. Information gained from the ESP monitoring is applicable to support the development of sealing technology to safely close a deep geological repository for the permanent disposal of radioactive wastes. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2022

User’s Manual for Seal_Flux: A Seal Barrier Reduced-Order Model

This report provides a brief description on the use of the Seal_Flux computer program developed as part of the effort to quantify the risk of geologic storage of carbon dioxide (CO 2 ) under the U.S. Department of Energy’s (DOE) National Risk Assessment Partnership (NRAP). The Seal_Flux code simulates the flow of CO 2 through a low permeability rock horizon or seal formation overlying the storage reservoir into which CO 2 is injected. A two-phase, relative permeability approach with Darcy’s law is used for one-dimensional (1D) flow computations of CO 2 through the horizon in the vertical direction. The code also allows the simulation of time-dependent processes that can influence such flow.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2026

ResStock Measure Documentation: Advanced Air Sealing, Attic Floor Insulation, and Duct Sealing and Insulation

This report is part of a series describing different ResStock measures. "Measures" refers to energy efficiency retrofits that can be applied to buildings during modeling. This documentation covers the "Advanced Air Sealing, Attic Floor Insulation, and Duct Sealing" measure upgrade methodology and briefly discusses key results.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2026

ResStock Measure Documentation: Advanced Air Sealing, Attic Floor Insulation, Duct Sealing and Insulation, and Drill-and-Fill Wall Insulation

This report is part of a series describing different ResStock measures. "Measures" refers to energy efficiency retrofits that can be applied to buildings during modeling. This documentation covers the "Advanced Air Sealing, Attic Floor Insulation, Duct Sealing and Insulation, and Drill-and-Fill Wall Insulation" measure upgrade methodology and briefly discusses key results.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2026

ResStock Measure Documentation: Light Air Sealing, Attic Floor Insulation, and Duct Sealing and Insulation

This report is part of series describing a variety of different ResStock(TM) measures. "Measures" refers to energy efficiency retrofits that can be applied to buildings during modeling. This documentation covers the "Light Envelope" measure upgrade methodology and briefly discusses key results. All results can be accessed on the ResStock Open Energy Data Initiative "End-Use Load Profiles for the U.S. Building Stock" data lake and on the data viewer at resstock.nlr.gov.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗