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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 1,063 records · Page 59
All sourcesNASA NTRSDOE OSTI
DOE OSTI2018

Dual-Zone Solar Control Indoor Shade: Demonstration at the Ronald V. Dellums Federal Building and U.S. Courthouse, 1301 Clay Street, Oakland, California and the Lawrence Berkeley National Laboratory Advanced Windows Testbed, Berkeley, California

Standard window shades are used to control sunlight, glare, window heat gains, and daylight. The challenge with conventional shades is that once the shades are lowered to reduce discomfort, daylight is reduced, which, in turn, increases the need for electric lighting. View is also obstructed, reducing the occupants’ connection to the outdoors. The strategy of subdividing the window wall and admitting daylight from above and controlling sunlight and view through the lower aperture can yield significant energy and peak demand savings over conventional shading systems, and improve the daylight quality of the indoor environment. This study evaluated a dual zone solar control (DZSC) shade with an upper, automated, horizontal, venetian blind with concave-up, matte white slats and a lower, manually operated, roller shade made of a transparent, reflective film. The automatic controls were designed to adjust the upper slat angle to maximize daylight to the room interior. The lower shade, when lowered, provided an unobstructed view to the outdoors. For the qualitative analysis, the DZSC shades were installed on windows in the southeast half of one floor in the Ronald V. Dellums Federal Building and U.S. Courthouse or hereafter referred to as the Oakland Federal Building (OFB) in Oakland, California. The position of the DZSC shades were observed and recorded periodically. Surveys were issued to occupants in the private offices and open plan workstations affected by the shades. For the quantitative analysis, the DZSC shades were installed in the south-facing windows of thermally isolated, fully instrumented, test chambers in the Advanced Windows Testbed at the Lawrence Berkeley National Laboratory (LBNL) in Berkeley, California. Measurements of window heat loads, daylight illuminance and environmental conditions related to visual and thermal comfort were collected over a six-month, solstice-to-solstice period. The performance of the DZSC shade was compared to fabric roller shades and venetian blinds since these are the two most common types of shades used in both commercial and Federal buildings. Several DZSC design permutations were evaluated: 1) manual or automated control of the upper louver system (“man” or “auto”) and 2) tinted or silvered reflective film for the lower shade (“Gray-Gray (GG)” or “Gray-Silver (GS)”1). The automated, reflective shade (auto-GS) reduced dimmable fluorescent lighting energy use by 51% and window cooling load by 13-15% compared to a conventional fabric roller shade with dual-pane, spectrally selective, low-e windows during the summer period (winter period was not measured). Qualitative analysis revealed that the auto-GS shade was preferred by 80% of the survey respondents compared to the existing vertical fabric blinds with single-pane, tinted windows in the occupied building. Survey results indicated that visual discomfort was reduced and thermal discomfort was also reduced during warm or hot weather. Occupants expressed greater satisfaction with the unobstructed view. Installation and commissioning of the DZSC shades was fairly straightforward with some minor problems due to inadequate installation instructions and improper wiring. A few occupants expressed dissatisfaction with the automatic controls for the upper louvers due to visual discomfort, erroneous control, and motor noise.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2019

Creep and Creep-Fatigue Crack Growth Mechanisms in Alloy709 — NEUPRC-3.2 (Final Report)

This report is a summary of the work carried out by an interdisciplinary team from USA (Department of Mechanical and Aerospace Engineering, North Carolina State University) and UK (School of Metallurgy and Materials, University of Birmingham) to study creep and creep-fatigue crack growth mechanisms of alloy 709 under plane stress and more constrained ‘plane strain’ conditions. While the US team was funded through the DOE-NEUP program, NEUP RC 3.2, 15-8432 the UK team was funded through Research Council UK Energy Program (RCUKEP) award number EP/N016351/1. The UK team’s program ends in September 2019, while the US program ends in December 2018. As such some of the activities of the program will continue till late 2019. The USA team utilized a novel technique including in-situ heating - loading and Scanning Electron Microscope (SEM) imaging to study the “real-time” crack growth of alloy 709 under plane stress conditions, while the UK team focused on ex-situ fatigue, creep and creep fatigue on larger samples under constrained conditions. Transmission Electron Microscope (TEM) characterization of samples before, during and after creep and creep-fatigue testing was used to address local deformation behavior, dislocation analysis and damage evaluation. Attention was directed towards establishing micro-mechanisms of fatigue crack growth, crack growth under dwell fatigue loading, creep and creep-fatigue crack growth at temperatures ranging from 500 to 750°C in air and in vacuum.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗
DOE OSTI2016

Thermal FEA for Front End Fixed Mask (SST)

The purpose of this study was to determine the temperature of the Fixed Mask using heat loads of the U42 Undulator. Finite Element Analysis was conducted on the fixed mask, to determine the temperature distribution on it, for 500 milli-amp current for NSLS-II. The Fixed mask has the sine wave surface profile.

36 MATERIALS SCIENCE↗
DOE OSTI2019

Engineered Barrier System R&D and International Collaborations – LANL (FY19)

Over the past seven years the Spent Fuel and Waste Science and Technology has investigated Engineered Barrier Systems (EBS) at higher heat loads (200 to 300 °C) and pressure (150 bar). This document presents the summary of Opalinus Clay experiments (EBS-14 to EBS26). These results include clay mineral analyses, authigenic mineral formation, and steel interface and corrosion results.

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

Materials and Dimensional Reference Handbook for the Boiling Water Reactor Dry Cask Simulator.

The performance of commercial nuclear spent fuel dry storage casks is evaluated through detailed analytical modeling of the system’s thermal performance. A recent investigation has been completed that produced a data set that can be used to test the validity of the modeling presently used to determine cladding temperatures in modern vertical dry casks. To produce these data sets under well-controlled boundary conditions, the dry cask simulator (DCS) was built to study the thermal-hydraulic response of fuel under a variety of heat loads, internal vessel pressures, and external configurations [Durbin and Lindgren, 2017]. The experiments were conducted in Albuquerque, New Mexico where the local ambient atmospheric pressure is typically 83 kPa. The purpose of this handbook is to document the pertinent geometric and material property information needed to perform model validation efforts.

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗
DOE OSTI2019

Towards Quantum-Limited Cryogenic Amplification for Multi-Qubit Platforms

Here we present the development of the building blocks of a Josephson parametric amplifier (JPA), namely the superconducting quantum interference device (SQUID) and the inductive pick-up coil that permits current coupling from a quantum dot into the SQUID. We also discuss our efforts in making depletion mode quantum dots using delta doped GaAs quantum wells. Because quantum dot based spin qubits utilize very low-level (~10 - 100pA), short duration (1ms - 1μs) current signals for state preparation and readout, these systems require close proximity cryogenic amplification to prevent signal corruption. Common amplification methods in these semiconductor quantum dots rely on heterojunction bipolar transistors (HBTs) and high electron mobility transistors (HEMTs) to amplify the readout signal from a single qubit. The state of the art for HBTs and HEMTs produce approximately 10µW of power when operating at high bandwidths. For few-qubit systems this level of heat dissipation is acceptable. However, for scaling up the number of qubits to several hundred or a thousand, the heat load produced in a 1 to 1 amplifier to qubit arrangement would overload the cooling capacity of a common dilution refrigerator, which typically has a cooling power of ~100µW at its base temperature. Josephson parametric amplifiers have been shown to dissipate ~1pW of power with current sensitivies on par with HBTs and HEMTs and with bandwidths 30 times that of HBTs and HEMTs, making them attractive for multi-qubit platforms. In this report we describe in detail the fabrication process flow for developing inductive pick-up coils and the fabrication and measurement of NbTiN and A1/A1Ox/A1 SQUIDs.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2019

Cryogenic RF tests of US LARP DQW SPS-series cavities

Crab cavities are one of the several components included in the luminosity upgrade of the Large Hadron Collider (HL-LHC). For nominal operation, the cavities have to provide a nominal deflecting kick of 3.4 MV per cavity in Continuous Wave operation at 2 K. The requirement for an unjacketed cavity – bare cavity equipped with Higher-Order Mode (HOM) filters and field antenna – is to reach at least a deflecting voltage of 4.1 MV (20% margin) with the heat load to the 2 K bath below 10 W. Cryogenic RF tests confirmed the required performances in bare cavities, with several cavities exceeding the required voltage by more than 50%. However, the first tests of a Double-Quarter Wave (DQW) cavity with one out of three HOM filters did not reach the required voltage. The present paper describes the studies and tests conducted to understand the limiting factor in the operation of a DQW cavity with HOM filters in the most up-to-date prototypes produced in the US and based on the DQW SPS-series design. The recipe to meet the performance specification for a bare DQW cavity with HOM filters and exceed the voltage requirement by more than 35% is discussed.

43 PARTICLE ACCELERATORS↗
DOE OSTI2019

Thermal Test of 29 mm and 12 mm Targets

NorthStar medical isotopes are planning to produce important medical radioisotope molybdenum-99 (Mo-99) through photonuclear reaction on molybdenum-100 (Mo-100). In this approach, multiple thin disks of enriched molybdenum metal will be bombarded with a 40-MeV electron beam. Because enriched Mo-100 is expensive, we intend to use as much beam power as possible to achieve maximum production yield and minimize the size of the target. This requirement leads to very high beam power density (heat deposition in the target),which sets challenging requirements for cooling. Together with scientists at Los Alamos National Laboratory, a team at Argonne National Laboratory has developed and demonstrated a cooling approach using pressurized helium, which allows for efficient heat removal. One of the challenges in this approach is the management of the heat load on the target window. The target window separates the high-pressure helium atmosphere inside the target from the vacuum in the beamline so it is constantly under stress from differential pressure. Also, the window is cooled only by the helium gas flow from one side, making the window design challenging. To validate calculation models, the team performed a series of tests at Argonne’s Low Energy Accelerator Facility (LEAF). This report describes additional tests for two target designs: a full-scale target 29 millimeters in diameter and a scaled-down version, 12 millimeters in diameter. We compared the results of the window temperature measurements and cooling system parameters obtained in the experiments with those predicted by analytical calculations and Computation Flow Dynamic (CFD) simulations. Results of the experiments and calculations are presented below.

07 ISOTOPE AND RADIATION SOURCES↗
DOE OSTI2020

Sodium-Cooled Fast Reactor Proliferation Resistance and Physical Protection White Paper

The Sodium-Cooled Fast Reactor (SFR) system was identified during the Generation IV Technology Roadmap as a promising technology to perform the actinide management mission and, if enhanced economics for the system could be realized, also the electricity and heat production missions. The main characteristics of the SFR that make it especially suitable for the actinide management mission are: Consumption of transuranics in a closed fuel cycle, thus reducing the radiotoxicity and heat load which facilitates waste disposal and geologic isolation; Enhanced utilization of uranium resources through efficient management of fissile materials and multi-recycle; and, High level of safety achieved through inherent and passive means that accommodate transients and bounding events with significant safety margins.

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗
DOE OSTI2017

Performance Specification 01000S, Building XXX Institutional General Plant Project

Design and construct a high-bay facility with penthouse mechanical area that meets the physical and functional requirements as described in this document. Using the Modular High Bay Programming Plan, contractor shall validate programming requirements including equipment to be installed; room sizes and quantities; heating, ventilation, and air- conditioning (HVAC) and electrical requirements, including sizing of equipment based on heat load; and other specific needs. Contractor shall provide the design development, engineering, construction drawings, construction and construction administration services required to completely define, document, and construct the facility to the requirements described in the Building XXX Programming Plan and those referenced herein.

42 ENGINEERING↗
DOE OSTI2019

SNL Contribution: Consequence Analysis for Moisture Remaining in Dry Storage Canisters After Drying

This report discusses several possible sources of water that could persist in SNF dry storage canisters through the drying cycle. In some cases, the water is trapped in occluded geometries in the cask such as dashpots or damaged fuel. Persistence of water or ice in such locations seems unlikely, given the high heat load of the canistered fuel; this is especially true in the case of vacuum drying, where a strong driver exists to remove water vapor from the headspace of such occluded geometries. Water retention in Boral® core material is a known problem, that has in the past resulted in the need for much extended drying times. Since the shift to slightly higher porosity "blister resistant" Boral®, water drainage appears to be less of a problem. However, high surface areas for the Boral® core material will provide a trap for significant amounts of adsorbed water, at least some of which is certain to survive the drying process. Moreover, if corrosion within the cores produces hydrous aluminum corrosion products, these may also survive.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2022

Optimization of a traveling wave superconducting radiofrequency cavity for upgrading the International Linear Collider

The standing wave TESLA niobium-based superconducting radio frequency structure is limited to an accelerating gradient of about 50 MV/m by the critical rf magnetic field. To break through this barrier, we explore the option of niobium-based traveling wave (TW) structures. Optimization of TW structures was done considering experimentally known limiting electric and magnetic fields. It is shown that a TW structure can have an accelerating gradient above 70 MeV/m that is about 1.5 times higher than contemporary standing wave structures with the same critical magnetic field. The other benefit of TW structures shown is R/Q about 2 times higher than the TESLA structure that reduces the dynamic heat load by a factor of 2. A method is proposed how to make TW structures multipactor-free. Some design proposals are offered to facilitate fabrication. Further increase of the real-estate gradient (equivalent to 80 MV/m active gradient) is also possible by increasing the length of the accelerating structure because of higher group velocity and cell-to-cell coupling. Realization of this work opens paths to International Linear Collider energy upgrades beyond 1 to 3 TeV in competition with CLIC. The paper will discuss corresponding opportunities and challenges.

43 PARTICLE ACCELERATORS↗
DOE OSTI2020

High-Performance Integrated Window and Façade Solutions for California

The researchers developed a new generation of high-performance façade systems and supporting design and management tools to support industry in meeting California’s greenhouse gas reduction targets, reduce energy consumption, and enable an adaptable response to minimize real-time demands on the electricity grid. The project resulted in five outcomes: (1) The research team developed an R-5, 1-inch thick, triplepane, insulating glass unit with a novel low-conductance aluminum frame. This technology can help significantly reduce residential cooling and heating loads, particularly during the evening. (2) The team developed a prototype of a windowintegrated local ventilation and energy recovery device that provides clean, dry fresh air through the façade with minimal energy requirements. (3) A daylight-redirecting louver system was prototyped to redirect sunlight 15–40 feet from the window. Simulations estimated that lighting energy use could be reduced by 35–54 percent without glare. (4) A control system incorporating physics-based equations and a mathematical solver was prototyped and field tested to demonstrate feasibility. Simulations estimated that total electricity costs could be reduced by 9-28 percent on sunny summer days through adaptive control of operable shading and daylighting components and the thermostat compared to state-of-the-art automatic façade controls in commercial building perimeter zones. (5) Supporting models and tools needed by industry for technology R&D and market transformation activities were validated. Attaining California’s clean energy goals require making a fundamental shift from today’s ad-hoc assemblages of static components to turnkey, intelligent, responsive, integrated building façade systems. These systems offered significant reductions in energy use, peak demand, and operating cost in California.

24 POWER TRANSMISSION AND DISTRIBUTION↗
DOE OSTI2021

Residual Insoluble Solids Expected from Saltcake Dissolution

A review of previous SRS saltcake dissolution and characterization studies was performed to inform the analysis of the amount of residual insoluble solids that may result from saltcake dissolution. A realistic value covering most cases for the maximum volume of a settled layer of residual insoluble solids that would result from dissolution of a volume of saltcake was calculated as 0.08 mL/mL (8 vol%). Applying factors to account for dissolution test uncertainty and differences between in-tank settling and laboratory testing, the recommended value for a settled layer of residual insoluble solids that would result from dissolution of a volume of saltcake is 0.16 mL/mL (16 vol%). This should apply to dissolution of saltcake with typical minimal amounts of entrained sludge but may not apply to saltcake with significant sludge. As it is composed of primarily non-radioactive isotopes, the precipitated aluminum hydroxide material does not contribute to the heat load.

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

A Novel Steam Condenser with Loop Thermosyphons and Film-Forming Agents for Improved Heat Transfer Efficiency and Durability

In this DOE/NETL BAA program, Advanced Cooling Technologies, Inc. (ACT), with Suez Water Technologies & Solutions (Suez), developed film-forming amine coatings applied to condenser surfaces that incorporated loop thermosyphons to enhance steam surface condenser performance and efficiency for coal-fired power plants. The condensation phenomenon resulting from these coatings promotes efficient dropwise condensation without additional thermal resistance through the use of film-forming amines (FFA). The loop thermosyphon technology was being developed to supplant current pumped cooling water systems to reduce operations and maintenance issues, reduce energy use, and promote high thermal performance. Both of ACT’s advanced coating and loop thermosyphon technologies were developed for application to wet cooling and indirect dry cooling systems. Internal steam condensation and subsequent heat dissipation complete the thermodynamic power cycle used by power plant cooling systems. The successful 3-year project period delved into understanding the experimental performance gain using film-forming amines applied to flat and tubular condenser surfaces under realistic operating conditions. The performance gain was used to create a technoeconomic analysis to more clearly understand the market value for power plants using FFA coatings to achieve dropwise condensation on condenser surfaces. A tall (50 ft.) loop thermosyphon was designed, fabricated, and tested to optimize the performance characteristics by tuning the working fluid charge and determining the temperature drop across the loop at different heat loads. Commercialization opportunities were explored to transition the loop thermosyphon work into the building HVAC market.

20 FOSSIL-FUELED POWER PLANTS↗
DOE OSTI2022

Valuing Residential Energy Efficiency: Analysis for a Prototypical Southeastern Utility [Slides]

The increasing amount of variable renewable energy resources and shifts towards more end-use and vehicle electrification suggests profound changes to power system planning and operation. Specifically, renewable energy is expected to shift net peak demand from late afternoon to early evening and end-use electrification may significantly increase winter peak demand. Residential energy efficiency is likely to align well with these shifts as it tends to produce savings in the early evening (e.g., from lighting measures) and coincident with heating loads (e.g., from envelope and space conditioning measures). Despite the opportunity to decrease system costs and emissions, residential energy efficiency is often limited by static valuation methods and its economic potential is considerably less than its technical potential. Using hourly residential energy efficiency characterizations, utility program cost data, and a capacity expansion model, we estimate the benefits of residential energy efficiency for a prototypical, summer-peaking utility in the Southeastern region. We first establish the cost-effective residential energy efficiency portfolio through “competition” with supply-side resources in a forward-looking capacity expansion model. Importantly, we then evaluate several scenarios intended to drive an increasing amount of cost-effective residential energy efficiency through measure cost reductions, increased customer adoption, policy goals (e.g., carbon price), and delivery of an integrated package of measures. The results quantify total system cost and emissions reductions, fossil-fuel plant retirements, and peak demand reductions. Results suggest the design and prioritization of policies and programs to access the untapped amount of cost-effective residential energy efficiency.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2022

Conceptual Design of Pulverized Coal Electricity Generating Units for Flexible Operation

This National Energy Technology Laboratory (NETL) study addresses the conceptual design of greenfield pulverized coal (PC) plants intended for flexible rather than high capacity factor baseload operation. The United States has plentiful, low-cost natural gas resources - studies of aggressive decarbonization scenarios of the US energy sector suggest that the variability of carbon-free power can be economically addressed using dispatchable natural gas-fueled generation. Globally, natural gas resources are not as plentiful or low cost; consequently, some regions of the world are anticipated to continue to rely upon coal generation, even as they pursue decarbonization efforts. To support the increased utilization of variable renewable generation in these coal-dependent regions, plant designs must target low-capacity factor coal plants with increased emphasis on flexibility attributes such as start-up times, ramp rates, minimum load, and part-load heat rates. While much work has been performed on the improvement of the flexibility for existing coal plants originally designed for baseload service, little public literature exists on clean sheet design for flexible operation. This conceptual design study aims to define the features, performance characteristics, and costs for greenfield coal plants intended for flexible operation. Quantifying these characteristics provides critical information required by utility owners, grid planners, energy market modelers, and energy policy decision makers in coal-dependent regions of the world to better understand how coal-fired power plants can support a transition to low carbon generation.

20 FOSSIL-FUELED POWER PLANTS↗
DOE OSTI2023

Cost and Performance Baseline for Fossil Energy Plants, Volume 5: Natural Gas Electricity Generating Units for Flexible Operation

To address the data needs of energy system designers and to serve as a baseline for research and development, NETL has carried out a study to characterize the flexibility attributes - both performance and cost - of nine common commercial natural gas-fueled electricity generating units. The intermittent output of low-carbon, renewable power generation sources such as wind and solar create challenges to grid stability and reliability. Fossil-fueled power generation technologies are currently used to provide reliable, on-demand power during periods of reduced renewable output. Dispatchable generators must be able to accommodate increasing renewable generation as the nation pursues the Administration’s target of a decarbonized energy sector by 2035. As energy system experts seek to identify least-cost approaches to decarbonization, accurate cost and performance data characterizing dispatchable fossil generators that operate flexibly, at capacity factors that have been declining over time, and are needed to inform models for capacity expansion. Furthermore, these technologies continue to be a significant source of carbon dioxide emissions, providing the impetus for research and development, including the advancement and potential incorporation of carbon capture technologies. This study characterizes the cost and performance of select state-of-the-art natural gas-fueled power generation technologies: reciprocating internal combustion engines (RICE), simple cycle combustion turbines, and natural gas combined cycles (NGCC). An emphasis is placed on flexibility characteristics, such as part-load heat rate, ramp rates, start up times, and start up costs.

03 NATURAL GAS↗