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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 1,369 records · Page 76
All sourcesNASA NTRSDOE OSTI
DOE OSTI2018

Including health in environmental impact assessments of three mega transport projects in Sydney, Australia: A critical, institutional, analysis

This article details how health impacts came to be assessed in three mega, billion dollar, transport infrastructure projects, two road tunnels and one light rail, in Sydney Australia. The known health impacts of transport decisions include environmental, behavioural and social factors. EIA practice prioritises environmental risks, and there has been scant attention to understanding why this is persistently the case. Here we provide a critical theory lens, using critical realist methodology, to analyse empirical data collected through interviews and documents for the three cases. Our analysis focusses on EIA practice within its institutional context, building on ‘new institutional’ approaches to policy analysis that emphasise actors (the stakeholders involved in the EIA), structures (the ‘rules of the game’ that influence practice in systems), and power. We find that the various actors engaged in the EIAs principally to address particular goals that were pre-determined by the system in which they worked or belonged. Structurally, each EIA was undertaken as a compliance process relatively late in the planning process. Considering project options was not part of the EIA's purpose. Resources to undertake the EIAs were provided by those funding the projects (“the proponents”) and determined the types of issues to be considered. The full range of links between transport and health were not identified. Concerning power, health impacts were considered through inter-professional technical negotiation. The inability to engage in the fundamental options driving projects meant impacted communities questioned the validity of the EIA, and the health assessment within this. Our institutional analysis provides important knowledge about how the EIAs preferenced a focus on specific health risks to the detriment of the known broader determinants that shape the health impacts of transport.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2013

Synthesis and catalytic application of nanofibrous La{sub 0.9}A{sub 0.1}MnO{sub 3} (A = Ca, Cu, Ag) with macroscopic shapes

Graphical abstract: Fabrication of nanofibrous La{sub 0.9}A{sub 0.1}MnO{sub 3} (A = Ca, Cu, Ag) perovskite-type oxides with macroscopic shapes was successfully obtained using carbon nanofibers (CNFs) as templates. Furthermore, their application for the combustion of carbon black (CB), which is a model of particulate matter exhausted from diesel engines, was demonstrated. - Highlights: • Nanofibrous La{sub 0.9}A{sub 0.1}MnO{sub 3} with macroscopic shapes was successfully obtained. • CNFs template method used here is facile, effective and reproducible. • The obtained materials show superior catalytic activity in soot combustion. • The catalytic order is La{sub 0.9}Ag{sub 0.1}MnO{sub 3} > La{sub 0.9}Cu{sub 0.1}MnO{sub 3} > La{sub 0.9}Ca{sub 0.1}MnO{sub 3}. - Abstract: Fabrication of nanofibrous La{sub 0.9}A{sub 0.1}MnO{sub 3} (A = Ca, Cu, Ag) perovskite-type oxides with macroscopic shapes can be successfully obtained by using CNFs as templates. Field emission scanning electron microscopy (FE-SEM) and X-ray diffraction (XRD) analysis confirmed the template effect and formation of nanofibrous perovskite-type oxides on macroscopic silica fiber. It turned out that it is reliable to control the desired single-phase La{sub 0.9}A{sub 0.1}MnO{sub 3} (A = Ca, Cu, Ag) perovskite-type oxides formation by tuning the corresponding metal ratio during preparation process. Furthermore, it showed that the as-prepared nanofibrous La{sub 0.9}A{sub 0.1}MnO{sub 3} (A = Ca, Cu, Ag) perovskite-type oxides can greatly decrease the combustion temperature of nanosized carbon black particles, and follows the order of La{sub 0.9}Ag{sub 0.1}MnO{sub 3} > La{sub 0.9}Cu{sub 0.1}MnO{sub 3} > La{sub 0.9}Ca{sub 0.1}MnO{sub 3}, indicating their high potential application prospects in diesel soot particles treatment.

36 MATERIALS SCIENCE↗
DOE OSTI2019

Directly visualizing the sign change of d-wave superconducting gap in Bi 2 Sr 2 CaCu 2 O 8+δ by phase-referenced quasiparticle interference

The superconducting state is formed by the condensation of Cooper pairs and protected by the superconducting gap. The pairing interaction between the two electrons of a Cooper pair determines the gap function. Thus, it is pivotal to detect the gap structure for understanding the mechanism of superconductivity. In cuprate superconductors, it has been well established that the gap may have a d-wave function. This gap function has an alternative sign change in the momentum space. It is however hard to visualize this sign change. Here we report the measurements of scanning tunneling spectroscopy in Bi 2 Sr 2 CaCu 2 O 8+δ and conduct the analysis of phase-referenced quasiparticle interference (QPI). We see the seven basic scattering vectors that connect the octet ends of the banana-shaped contour of Fermi surface. The phase-referenced QPI clearly visualizes the sign change of the d -wave gap. Lastly, our results illustrate an effective way for determining the sign change of unconventional superconductors.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2025

Atomic-scale 3D structural dynamics and functional degradation of Pt alloy nanocatalysts during the oxygen reduction reaction

Pt-based electrocatalysts are the primary choice for fuel cells due to their superior oxygen reduction reaction (ORR) activity. To enhance ORR performance and durability, extensive studies have investigated transition metal alloying, doping, and shape control to optimize the three key governing factors for ORR: geometry, local chemistry, and strain of their surface and subsurface. However, systematic optimization remains incomplete, as it requires an atomic-scale understanding of these factors and their dynamics over potential cycling, as well as their relationship to ORR activity. Here, we implement neural network-assisted atomic electron tomography to measure the 3D atomic structural dynamics and their effects on the functional degradation of PtNi alloy catalysts. Our results reveal that PtNi catalysts undergo shape changes, surface alloying, and strain relaxation during cycling, which can be effectively mitigated by Ga doping. By combining geometry, local chemistry, and strain analysis, we calculated the changes in ORR activity over thousands of cycles and observed that Ga doping leads to higher initial activity and greater stability. These findings offer a pathway to understanding 3D atomic structural dynamics and their relation to ORR activity during cycling, paving the way for the systematic design of durable, high-efficiency nanocatalysts.

Jeong, Chaehwa↗
DOE OSTI2015

Triazolium based ionic liquid crystals: Effect of asymmetric substitution

A new series of ten different asymmetrical 1-dodecyl-3-alkyl-triazolium bromides, [C 12 C n Tr][Br], has been synthesized and their mesomorphic behavior studied by DSC (differential scanning calorimetry), POM (polarizing optical microscopy) and SAXS (small angle X-ray scattering). The influence of the chain length of the triazolium salts is investigated to explore the effect of asymmetric substitution on the phase behaviour of these compounds. For that reason, the length of one alkyl chain was varied from 14 to 1 carbon atoms (n = 14, 12, 10, 8–4, 2, 1) while the other alkyl chain was kept at 12 carbon. Single crystal X-ray structure analysis of compounds [C 12 C 12 Tr][Br] and [C 12 C 5 Tr][Br] reveal that the cations adopt a U-shaped conformation with head-to-head arranged triazolium cores. In contrast, for [C 12 C 1 Tr][Br], a rod like shape of the cation with interdigitated alkyl chains is found. All investigated compounds are thermotropic liquid crystals. Higher ordered smectic phases, smectic C as well as smectic A phases were found depending on the chain length of the cation. Moreover, the clearing point temperature decreases with decreasing chain length with exception for the n-dodecyl-3-alkyltrizoliumbromides with the two shortest alkyl chains, [C 12 C 2 Tr][Br] and [C 12 C 1 Tr][Br], which present higher clearing temperatures (86 and 156 °C) and are structurally distinctly different.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2019

Hot-electron effects during reactive scattering of H 2 from Ag(111): the interplay between mode-specific electronic friction and the potential energy landscape

The breakdown of the Born–Oppenheimer approximation gives rise to nonadiabatic effects in gas-surface reactions at metal surfaces. However, for a given reaction, it remains unclear which factors quantitatively determine whether these effects measurably contribute to surface reactivity in catalysis and photo/electrochemistry. Here, we systematically investigate hot electron effects during H 2 scattering from Ag(111) using electronic friction theory. We combine first-principles calculations of tensorial friction by time-dependent perturbation theory based on density functional theory and an analytical neural network representation, to overcome the limitations of existing approximations and explicitly simulate mode-specific nonadiabatic energy loss during molecular dynamics. Despite sizable hot-electron-induced energy loss, no measurable nonadiabatic effects can be found for H 2 scattering on Ag(111). This is in stark contrast to previous reports for vibrationally excited H 2 scattering on Cu(111). By detailed analysis of the two systems, we attribute this discrepancy to a subtle interplay between the magnitude of electronic friction along intramolecular vibration and the shape of the potential energy landscape that controls the molecular velocity at impact. On the basis of this characterization, we offer guidance for the search of highly nonadiabatic surface reactions.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2021

2D coherence imaging measurements of C 2+ ion temperatures in the divertor of Wendelstein 7-X

For the first time, 2D ion temperature values are derived from coherence imaging spectroscopy (CIS) fringe contrast measurements by taking Zeeman line broadening effects into account during the analysis procedure of a spatial-heterodyne CIS instrument. This allowed 2D images of C 2+ ion temperatures (T i ) across the 3D-shaped island divertor of the Wendelstein 7-X stellarator. Ion temperatures ranging from 10 to 20 eV are observed for the C 2+ impurity species in the region above the divertor targets. During the transition from the attached to the detached plasma state, the C 2+ radiation zone moves from close to the divertor target towards the last closed flux surface. Within this radiation zone, C 2+ temperature does not decrease significantly. Experimentally, the coherence imaging measurements were cross-calibrated at one poloidal cross-section using a high resolution Echelle spectrometer, that shared its sightlines with the coherence imaging diagnostic. The spectra demonstrated that, apart from Doppler broadening, the Zeeman effect significantly contributes to the spectral line broadening and cannot be neglected when analyzing the CIS contrast data for T i extraction in the edge and scrape-off-layer of Wendelstein 7-X (W7-X), due to the relatively low temperatures (T i < 100 eV) and high magnetic fields (B ≈ 2.5 T).

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
DOE OSTI2024

GaN-based W-band receiver chip development for fusion plasma diagnostics

Millimeter-wave diagnostics have proven effective on various magnetic fusion devices worldwide, yet the formidable challenges posed by the harsh environments of future burning plasma devices, characterized by extreme temperatures, pressures, and radiation levels, remain a significant hurdle. To address these challenges, the utilization of wide bandgap Gallium Nitride (GaN)-based millimeter-wave diagnostics is a most promising solution for fusion reactor safety monitoring and control. A noteworthy W-band GaN-based system-on-chip receiver has been the demonstrated by employing HRL T3 40 nm GaN technology. This receiver chip, compactly designed with dimensions of 3 × 5 mm 2 , incorporates essential components such as the 75–110 GHz RF Low-Noise Amplifier (LNA), mixer, Intermediate Frequency (IF) amplifier, and Local Oscillator (LO) chain. This receiver chip will be packaged as a millimeter-wave receiver module and applied on the DIII-D National Fusion Facility, for fusion plasma edge shape monitoring for operational safety and dangerous disruption prediction. The laboratory measurement results have demonstrated suitable performance. Furthermore, this advancement is pivotal for accurate analysis of plasma behavior in the extreme conditions of burning plasma devices, driving progress in fusion research and technology.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
DOE OSTI2019

Dark Energy Survey year 1 results: the relationship between mass and light around cosmic voids

What are the mass and galaxy profiles of cosmic voids? In this paper, we use two methods to extract voids in the Dark Energy Survey (DES) Year 1 redMaGiC galaxy sample to address this question. We use either 2D slices in projection, or the 3D distribution of galaxies based on photometric redshifts to identify voids. For the mass profile, we measure the tangential shear profiles of background galaxies to infer the excess surface mass density. The signal-to-noise ratio for our lensing measurement ranges between 10.7 and 14.0 for the two void samples. We infer their 3D density profiles by fitting models based on N-body simulations and find good agreement for void radii in the range 15–85 Mpc. Comparison with their galaxy profiles then allows us to test the relation between mass and light at the 10 per cent level, the most stringent test to date. We find very similar shapes for the two profiles, consistent with a linear relationship between mass and light both within and outside the void radius. We validate our analysis with the help of simulated mock catalogues and estimate the impact of photometric redshift uncertainties on the measurement. Our methodology can be used for cosmological applications, including tests of gravity with voids. Finally, this is especially promising when the lensing profiles are combined with spectroscopic measurements of void dynamics via redshift-space distortions.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2017

Concurrent determination of nanocrystal shape and amorphous phases in complex materials by diffraction scattering computed tomography

Advanced functional materials often contain multiple phases which are (nano)crystalline and/or amorphous. The spatial distribution of these phases and their properties, including nanocrystallite size and shape, often drives material function yet is difficult to obtain with current experimental techniques. This article describes the use of diffraction scattering computed tomography, which maps wide-angle scattering information onto sample space, to address this challenge. The wide-angle scattering signal contains information on both (nano)crystalline and amorphous phases. Rietveld refinement of reconstructed diffraction patterns is employed to determine anisotropic nanocrystal shapes. The background signal from refinements is used to identify contributing amorphous phases through multivariate curve resolution. Thus it is demonstrated that reciprocal space analysis in combination with diffraction scattering computed tomography is a very powerful tool for the complete analysis of complex multiphase materials such as energy devices.

Birkbak, Mie Elholm↗
DOE OSTI2020

Towards the spatial resolution of metalloprotein charge states by detailed modeling of XFEL crystallographic diffraction

Oxidation states of individual metal atoms within a metalloprotein can be assigned by examining X-ray absorption edges, which shift to higher energy for progressively more positive valence numbers. Indeed, X-ray crystallography is well suited for such a measurement, owing to its ability to spatially resolve the scattering contributions of individual metal atoms that have distinct electronic environments contributing to protein function. However, as the magnitude of the shift is quite small, about +2 eV per valence state for iron, it has only been possible to measure the effect when performed with monochromated X-ray sources at synchrotron facilities with energy resolutions in the range 2–3 × 10 −4 (Δ E / E ). This paper tests whether X-ray free-electron laser (XFEL) pulses, which have a broader bandpass (Δ E / E = 3 × 10 −3 ) when used without a monochromator, might also be useful for such studies. The program nanoBragg is used to simulate serial femtosecond crystallography (SFX) diffraction images with sufficient granularity to model the XFEL spectrum, the crystal mosaicity and the wavelength-dependent anomalous scattering factors contributed by two differently charged iron centers in the 110-amino-acid protein, ferredoxin. Bayesian methods are then used to deduce, from the simulated data, the most likely X-ray absorption curves for each metal atom in the protein, which agree well with the curves chosen for the simulation. The data analysis relies critically on the ability to measure the incident spectrum for each pulse, and also on the nanoBragg simulator to predict the size, shape and intensity profile of Bragg spots based on an underlying physical model that includes the absorption curves, which are then modified to produce the best agreement with the simulated data. This inference methodology potentially enables the use of SFX diffraction for the study of metalloenzyme mechanisms and, in general, offers a more detailed approach to Bragg spot data reduction.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2016

TH-CD-BRA-02: 3D Remote Dosimetry for MRI-Guided Radiation Therapy: A Hybrid Approach

Purpose: To validate the dosimetric accuracy of a commercially available MR-IGRT system using a combination of 3D dosimetry measurements (with PRESAGE(R) radiochromic plastic and optical-CT readout) and an in-house developed GPU-accelerated PENELOPE Monte-Carlo dose calculation system. Methods: {sup 60}Co IMRT subject to a 0.35T lateral magnetic field has recently been commissioned in our institution following AAPM’s TG-119 recommendations. We performed PRESAGE(R) sensitivity studies in 4ml cuvettes to verify linearity, MR-compatibility, and energy-independence. Using 10cm diameter PRESAGE(R), we delivered an open calibration field to examine the percent depth dose and a symmetrical 3-field plan with three adjacent regions of varying dose to determine uniformity within the dosimeter under a magnetic field. After initial testing, TG-119 plans were created in the TPS and then delivered to 14.5cm 2kg PRESAGE(R) dosimeters. Dose readout was performed via optical-CT at a second institution specializing in remote 3D dosimetry. Absolute dose was measured using an IBA CC01 ion chamber and the institution standard patient-specific QA methods were used to validate plan delivery. Calculated TG-119 plans were then compared with an independent Monte Carlo dose calculation (gPENELOPE). Results: PRESAGE(R) responds linearly (R{sup 2}=0.9996) to {sup 60}Co irradiation, in the presence of a 0.35T magnetic field, with a sensitivity of 0.0305(±0.003)cm{sup −1}Gy{sup −1}, within 1% of a 6MV non-MR linac irradiation (R{sup 2}=0.9991) with a sensitivity of 0.0302(±0.003)cm{sup −1}Gy{sup −1}. Analysis of TG-119 clinical plans using 3D-gamma (3%/3mm, 10% threshold) give passing rates of: HN 99.1%, prostate 98.0%, C-shape 90.8%, and multi-target 98.5%. The TPS agreed with gPENELOPE with a mean gamma passing rate of 98.4±1.5% (2%/2mm) with the z-score distributions following a standard normal distribution. Conclusion: We demonstrate for the first time that 3D remote dosimetry using both experimental and computational methods is a feasible and reliable approach to commissioning MR-IMRT, which is particularly useful for less specialized clinics in adopting this new treatment modality.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2023

The mechanics of plant morphogenesis

Understanding the mechanism by which patterned gene activity leads to mechanical deformation of cells and tissues to create complex forms is a major challenge for developmental biology. Plants offer advantages for addressing this problem because their cells do not migrate or rearrange during morphogenesis, which simplifies analysis. We synthesize results from experimental analysis and computational modeling to show how mechanical interactions between cellulose fibers translate through wall, cell, and tissue levels to generate complex plant tissue shapes. Genes can modify mechanical properties and stresses at each level, though the values and pattern of stresses differ from one level to the next. Here, the dynamic cellulose network provides elastic resistance to deformation while allowing growth through fiber sliding, which enables morphogenesis while maintaining mechanical strength.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2018

Development of a Simple and Rapid Diagnostic Method for Polymer-Electrolyte Fuel Cells

A simple and fast diagnostic tool has been developed for analyzing polymer-electrolyte fuel-cell degradation. The tool is based on analyzing changes in polarization curves of a cell over its lifetime. The shape of the polarization-change curve and its sensitivity to oxygen concentration are found to be unique for each degradation pathway based on analysis from a detailed 2-D numerical model of the cell. Using the polarization-change curve methodology, the primary mechanism for degradation (kinetic, ohmic, and/or transport related) can be identified. Here, the technique is applied to two sets of data to explain performance changes after two different cells undergo voltage-cycling accelerated stress test, where it is found that changes are kinetic and then ohmic or transport in nature depending on the cell type. The diagnostic tool provides a simple method for rapid determination of primary degradation mechanisms. Finally, areas for more detailed future investigations are also summarized.

08 HYDROGEN↗
DOE OSTI2015

Influence of the North Atlantic SST Variability on the Atmospheric Circulation during the Twentieth Century

The ocean–atmosphere coupling in the North Atlantic is investigated during the twentieth century using maximum covariance analysis of sea surface temperature (SST) and 500-hPa geopotential height analyses and performing regressions on dynamical diagnostics such as Eady growth rate, wave activity flux, and velocity potential. The North Atlantic Oscillation (NAO) generates the so-called SST anomaly tripole. A rather similar SST anomaly tripole, with the subpolar anomaly displaced to the east and a more contracted subtropical anomaly, which is referred to as the North Atlantic horseshoe pattern, in turn influences the atmosphere. In the fall and early winter, the response is NAO like and primarily results from subpolar forcing centered over the Labrador Sea and off Newfoundland. In summer, the largest atmospheric response to SST resembles the east Atlantic pattern and results from a combination of subpolar and tropical forcing. To emphasize the interannual to multidecadal variability, the same analysis is repeated after low-pass filtering. The SST influence is dominated by the Atlantic multidecadal oscillation (AMO), which also has a horseshoe shape, but with larger amplitude in the subpolar basin. A warm AMO phase leads to an atmospheric warming limited to the lower troposphere in summer, while it leads to a negative phase of the NAO in winter. The winter influence of the AMO is suggested to be primarily forced by the Atlantic SSTs in the northern subtropics. Such influence of the AMO is found in winter instead of early winter because the winter SST anomalies have a larger persistence, presumably because of SST reemergence.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2016

High-Resolution, Non-Invasive Imaging of Upper Vocal Tract Articulators Compatible with Human Brain Recordings

A complete neurobiological understanding of speech motor control requires determination of the relationship between simultaneously recorded neural activity and the kinematics of the lips, jaw, tongue, and larynx. Many speech articulators are internal to the vocal tract, and therefore simultaneously tracking the kinematics of all articulators is nontrivial-especially in the context of human electrophysiology recordings. Here, we describe a noninvasive, multi-modal imaging system to monitor vocal tract kinematics, demonstrate this system in six speakers during production of nine American English vowels, and provide new analysis of such data. Classification and regression analysis revealed considerable variability in the articulator-to-acoustic relationship across speakers. Non-negative matrix factorization extracted basis sets capturing vocal tract shapes allowing for higher vowel classification accuracy than traditional methods. Statistical speech synthesis generated speech from vocal tract measurements, and we demonstrate perceptual identification. We demonstrate the capacity to predict lip kinematics from ventral sensorimotor cortical activity. These results demonstrate a multi-modal system to non-invasively monitor articulator kinematics during speech production, describe novel analytic methods for relating kinematic data to speech acoustics, and provide the first decoding of speech kinematics from electrocorticography. These advances will be critical for understanding the cortical basis of speech production and the creation of vocal prosthetics.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2017

Impacts of Using Distributed Energy Resources to Reduce Peak Loads in Vermont

To help the United States develop a modern electricity grid that provides reliable power from multiple resources as well as resiliency under extreme conditions, the U.S. Department of Energy (DOE) is leading the Grid Modernization Initiative (GMI) to help shape the future of the nation's grid. Under the GMI, DOE funded the Vermont Regional Initiative project to provide the technical support and analysis to utilities that need to mitigate possible impacts of increasing renewable generation required by statewide goals. Advanced control of distributed energy resources (DER) can both support higher penetrations of renewable energy by balancing controllable loads to wind and photovoltaic (PV) solar generation and reduce peak demand by shedding noncritical loads. This work focuses on the latter. This document reports on an experiment that evaluated and quantified the potential benefits and impacts of reducing the peak load through demand response (DR) using centrally controllable electric water heaters (EWHs) and batteries on two Green Mountain Power (GMP) feeders. The experiment simulated various hypothetical scenarios that varied the number of controllable EWHs, the amount of distributed PV systems, and the number of distributed residential batteries. The control schemes were designed with several objectives. For the first objective, the primary simulations focused on reducing the load during the independent system operator (ISO) peak when capacity charges were the primary concern. The second objective was to mitigate DR rebound to avoid new peak loads and high ramp rates. The final objective was to minimize customers' discomfort, which is defined by the lack of hot water when it is needed. We performed the simulations using the National Renewable Energy Laboratory's (NREL's) Integrated Energy System Model (IESM) because it can simulate both electric power distribution feeder and appliance end use performance and it includes the ability to simulate multiple control strategies.

24 POWER TRANSMISSION AND DISTRIBUTION↗
DOE OSTI2024

Salt Tank Testbed: a Test Site Designed to Replicate Floor Buckles Observed in Commercial TES Tanks

A test site has been designed and is under construction to replicate the buckling failure ob-served in several in-service storage tanks for nitrate salts operating up to 565°C. In commercial tanks multiple factors have been identified that influence the floors susceptibility to buck-ling, including: the as-manufactured shape of the floor, high compressive stresses due to thermal gradients and/or friction, fluid inventory and absolute temperature. Based on exten-sive modeling analysis it was determined that similar buckles can be reproduced in a scaled test tank (approximately 9x smaller than a representative commercial tank design). To buckle the scaled tank a radial thermal gradient is generated in the tank with a low fluid level, the fluid level is then increased while maintaining the thermal gradient; based on the modeling results just one of these cycles can plastically deform the tank floor. The test site which is under construction is designed to replicate this damaging cycle at lower temperatures. The goal of testing will be to reproduce this damaging cycle and buckle the scaled test tank floor, allowing proper model validation and a methodology for comparing different tank designs at a smaller (and less costly) scale.

25 ENERGY STORAGE↗