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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 235 records · Page 13
All sourcesNASA NTRSDOE OSTI
NASA NTRS2015

Thirsty Walls: A New Paradigm for Air Revitalization in Life Support

Carbon Dioxide removal systems on submarines are compact and reliable. They use solubility chemistry. They spray a Carbon Dioxide adsorbing chemical directly into the air stream, and allow the liquid to settle. Carbon Dioxide removal systems on ISS are large and need repair. They use adsorption chemistry. They force air through a bed packed with granular zeolite, and heat the bed to desorb the Carbon Dioxide. The thermal cycles cause the zeolite to dust. New advances in additive manufacturing, and a better understanding of uid behavior in microgravity make it possible to expose a liquid directly to air in a microgravity environment. It is now practical to use submarine style solubility chemistry for atmosphere revitalization in space. It is now possible to develop space systems that achieve submarine levels of reliability. New developments in Ionic Liquid research make it possible to match the solubility performance characteristics of MEA used on submarines - with Ionic Liquids that do not release chemical vapors into the air. "Thirsty Walls" provide gentle, passive contact between ventilation air and Air Revitalization functions of temperature control, relative humidity control, and Carbon Dioxide removal. "Thirsty Walls" eliminates the need of large blowers and compressors that need to force air at high velocities through restrictive Air Revitalization hardware.

Graf, John↗
DOE OSTI2026

Commissioning of an MPGD-based Drift Chamber for Heavy-ion Tracking in FRIB's Sweeper magnet system

A newly developed drift chamber equipped with an innovative hybrid Micro-Pattern Gaseous Detector based readout was commissioned at FRIB. The detector consists of a Multi-layer Thick Gas Electron Multiplier (M-THGEM) mounted over a high-granularity, position-sensitive readout board. Denoted as the Micro-Pattern Drift Chamber (MPDC), the new device is used to provide tracking capability as part of the detectors of the Sweeper magnet system for neutron-invariant-mass spectrometry at the Facility for Rare Isotope Beams (FRIB). The localization of impinging ions in a 30 × 30 cm 2 drift area is derived by processing the charge-avalanche distribution induced on the segmented readout board. The signals induced on the readout pads are processed by a compact, multi-channel Data Acquisition System (DAQ) based on the Scalable Readout System (SRS). To facilitate synchronization with other detector systems of the Sweeper magnet system, the SRS has been configured to accept an external trigger.

Gaseous detectors↗
DOE OSTI2024

Time projection chamber for GADGET II

The established Gaseous Detector with Germanium Tagging (GADGET) detection system is used to measure weak, low-energy 𝛽-delayed proton decays. It consists of the Gaseous Proton Detector equipped with a MICROMEGAS (MM) readout to detect protons and other charged particles calorimetrically, surrounded by the Segmented Germanium Array (SeGA) for high-resolution detection of prompt 𝛾 rays. To upgrade GADGET's Proton Detector to operate as a compact time projection chamber (TPC) for the detection, three-dimensional imaging and identification of low-energy 𝛽-delayed single- and multiparticle emissions mainly of interest to astrophysical studies. A new high granularity MM board with 1024 pads has been designed, fabricated, installed, and tested. A high-density data acquisition system based on generic electronics for TPCs (GET) has been installed and optimized to record and process the gas avalanche signals collected on the readout pads. The TPC's performance has been tested using a 220 Rn 𝛼-particle source and cosmic-ray muons. In addition, decay events in the TPC have been simulated by adapting the attpcroot data analysis framework. Furthermore, a novel application of two-dimensional convolutional neural networks for GADGET II event classification is introduced. The optimization of data throughput is also addressed. The GADGET II TPC is capable of detecting and identifying 𝛼 particles as well as measuring their track direction, range, and energy. The extracted energy resolution of the GADGET II TPC using P10 gas is about 5.4% at 6.288 MeV ( 220 Rn 𝛼 events), computed using charge integration. Based on a systematic simulation study, we estimated the detection efficiency of the GADGET II TPC for protons and 𝛼 particles, respectively. It has also been demonstrated that the GADGET II TPC is capable of tracking minimum-ionizing particles (i.e., cosmic-ray muons). From these measurements, the electron drift velocity was measured under typical operating conditions. In addition to being one of the first generation of micropattern gaseous detectors (MPGDs) to utilize a resistive anode applied to low-energy nuclear physics, the GADGET II TPC will also be the first TPC surrounded by a high-efficiency array of high-purity germanium 𝛾-ray detectors. As a result, the TPC of GADGET II has been designed, fabricated, and tested and is ready for operation at the Facility for Rare Isotope Beams for radioactive-beam-line experiments.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
NASA NTRS2012

Balanced mechanical resonator for powder handling device

A system incorporating a balanced mechanical resonator and a method for vibration of a sample composed of granular material to generate motion of a powder sample inside the sample holder for obtaining improved analysis statistics, without imparting vibration to the sample holder support.

Sarrazin, Philippe C.↗
NASA NTRS2009

Study of Electro-Cyclonic Filtration and Pneumatic Transfer of Lunar Regolith Simulants under 1/6-g and 1-g Gravity Conditions

NASA has built a prototype oxygen production plant to process the lunar regolith using the hydrogen reduction chemical process. This plant is known as "ROxygen - making oxygen from moon rocks". The ROxygen regolith transfer team has identified the flow and transfer characteristics of lunar regolith simulant to be a concern for lunar oxygen production efforts. It is important to ISRU lunar exploration efforts to develop hardware designs that can demonstrate the ability to flow and transfer a given mass of regolith simulant to a desired vertical height under lunar gravity conditions in order to introduce it into a reactor. We will present results obtained under both 1/6-g and 1-g gravity conditions for a system that can pneumatically convey 16.5 kg of lunar regolith simulant (NU-LHT-2M, Mauna Kea Tephra, and JSC-1A) from a flat-bottom supply hopper to a simulated ISRU reactor (dual-chambered receiving hopper) where the granular material is separated from the convey gas (air) using a series of cyclone separators, one of which is an electrically enhanced cyclone separator (electrocyclone). The results of our study include (1) the mass flow rate as a function of input air pressure for lunar regolith simulants that are conveyed pneumatically as a dusty gas in a vertical direction against gravity under lunar gravity conditions (for NU-LHT-2M and Mauna Kea Tephra), and under earth gravity conditions (for NU-LHT-2M, Mauna Kea Tephra and JSC-1A), and (2) the efficiency of the cyclone/electrocyclone filtration system in separating the convey gas (air) from the granular particulates as a function of particle size.

Mantovani, James G.↗
DOE OSTI2020

Isotopic analysis of plutonium measured with very thick absorbers and high-granularity spectra

FRAM is LANL-designed software designed to extract plutonium and uranium isotopic information from gamma ray spectra. This is an important capability for NEST and STAB; however, FRAM performance has been poor when applied to field data collected in these programs. FRAM Version 5 (commercially available) was fine-tuned and validated for laboratory quality measurements but not for measurements of the high-mass and heavily shielded SNM items encountered in NEST. FRAM is untested for spectra collected with high-granularity lower resolution instruments such as the new 8-MeV Detective-X favored by STAB or the new custom electrocooled systems coming into use for NEST. FRAM Version 6.1 (unreleased) has improvements in physics capabilities, and parameter sets may be adapted that are more specific to NEST and STAB, which is what we have attempted for this assignment. Thick shielding attenuates gamma rays profoundly, especially those at low energy, making them too weak to be measured. The missing low-energy peaks force the analysis to employ only the highest-energy peaks. We adapted FRAM 6.1 for analysis of plutonium spectra obtained with very thick Pb filters (a surrogate for NEST-type configurations). New parameter sets employing only very high energy peaks were created for the analysis. High granularity and low resolution make deconvolution of the 600-keV region particularly challenging, and we have worked to optimally extract information from this region. The results shown in this paper give high confidence that we are on the right track. We used a combination of real and synthetically-modified data. Remaining work includes testing the new software and parameters against genuine data collected with Detective-X and new NEST systems, but such datasets at the moment are unavailable. It also remains to develop and test parameter sets specific to uranium and the new detectors.

07 ISOTOPE AND RADIATION SOURCES↗
DOE OSTI2021

Case Study: Field Evaluation of a Low-Cost Circuit-Level Electrical Submetering System

Circuit-level metering technologies provide the ability to monitor individual circuits within an electrical panel in a building, providing detailed power and energy consumption data at a much more granular level than was previously achievable in a cost-effective manner. While the fundamental hardware components of circuit-level—split-core current transformers (CTs) and power monitoring meters—have existed for some time, the new offerings in the market have tightly integrated these components, lower costs, and have streamlined data organization, transport, and access via software solutions accessible through web and application programming interfaces (API). NREL evaluated Meazon’s single-circuit metering system. The evaluation of the equipment under test (EUT) focused on three aspects: (1) accuracy of the data provided by the system, (2) ease of installation of this technology and ease of data integration into existing U.S. General Services Administration (GSA) analytics platforms, and (3) total cost of ownership and cost-effectiveness of the technology. The metering technology was tested in a field deployment where it was installed in low and high-voltage commercial electrical panels in the César E. Chávez Memorial Building in Denver, Colorado. The goals were to assess the metering accuracy, the ease of installation and data retrieval, and the total cost of ownership and cost-effectiveness. This technology proved easy to install by a certified electrician who completed the install of 6 meters in 2 separate panels (120/208 V and 277/480 V) and 2 circuit disconnects (along with associated commissioning) at the César E. Chávez Memorial Building in less than one day. The technology was installed in high- and low-voltage panels and with limited space in the electrical room, demonstrating the applicability of this technology to almost all commercial buildings in the GSA portfolio. Primary considerations for this technology include appropriate sizing of CTs for each circuit, selection of loads/circuits/panels that are of high value for detailed submetering (e.g., tailored for high-load devices), and how GSA would like to integrate these data with its existing energy management infrastructure. Through the field evaluation, we demonstrated data integration from the vendor system into the primary software component on the GSA enterprise-level energy management and information system, GSA Link. Data from the circuit-level metering were integrated into this platform and used to perform FDD. This demonstrated the ability of the EUT to augment existing energy management and information systems in buildings where GSA Link is deployed and provides a pathway for delivering FDD at other buildings throughout the portfolio.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2022

Prototype College Building Energy Model: Building Characteristics and Energy Simulation Results

The US Department of Energy supports the development of commercial building energy codes and standards. To support commercial building energy research activities and the development of commercial building energy codes and standards, continuous efforts have been made to convert 16 prototype building models, which cover 80% of US commercial building floor space, to OpenStudio prototype buildings. Additionally, the suite of prototype building models was expanded to include the addition of new building prototype models (e.g., courthouse, college building). Multiple sources, including databases, documented projects, and personal communications, were used to define the prototype college building, and a 4-story with 69,063 ft 2 building was considered as the prototype college building to represent an average-sized college building in the United States. To represent realistic occupancy schedules and increase the granularity of information, actual class reservation schedules were collected and used. This report documents the building and system characteristics of the prototype college building model combined with climate-specific and construction vintage–specific requirements for the building envelope and systems from ASHRAE Standard 90.1. The energy simulation results are presented for 4 construction vintages (2004, 2007, 2010, and 2013) and 15 ASHRAE climate zones. The site energy use intensity of the college building was compared with 2012 Commercial Building Energy Consumption Survey (CBECS) and ENERGY STAR data to verify the simulation results. The site energy use intensity of the college building ranged from 60 to 202.4 kBtu/ft 2 , and compared with the energy use intensities of Commercial Building Energy Consumption Survey (122.9 kBtu/ft 2 ) and ENERGY STAR (84.3 kBtu/ft 2 ) data, the prototype college building results are in a reasonable range.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2026

Pixel-Strip Module Testing and Performance Analysis for the CMS Phase-2 Outer Tracker Upgrade

In response to the demanding environment of the High-Luminosity Large Hadron Collider (HL-LHC), the Compact Muon Solenoid (CMS) Experiment's Outer Tracker is being replaced with a lighter, higher-granularity, radiation-tolerant silicon detector capable of providing tracking information directly to the Level-1 trigger system. The new Outer Tracker consists of Pixel-Strip (PS) and Strip-Strip (2S) transverse momentum (pT) modules, which are assembled and tested at, among other centers, Fermilab's Silicon Detector Facility. PS modules consist of a pixel sensor, a strip sensor, and multiple application-specific integrated circuits (ASICs). This poster studies the performance of MaPSAs, silicon macro-pixel sensors bump-bonded to 16 macro-pixel ASICS. It presents the testing procedures for MaPSAs and MaPSA-strip sensor sub-assemblies, as well as the results of calibration and performance studies of two PS modules before and after irradiation. These results assess the impact of irradiation on module performance, providing insight into the modules' expected performance in the HL-LHC environment.

Kimrey, Emerson [Scripps College]↗
NASA NTRS1985

PISCES: An environment for parallel scientific computation

The parallel implementation of scientific computing environment (PISCES) is a project to provide high-level programming environments for parallel MIMD computers. Pisces 1, the first of these environments, is a FORTRAN 77 based environment which runs under the UNIX operating system. The Pisces 1 user programs in Pisces FORTRAN, an extension of FORTRAN 77 for parallel processing. The major emphasis in the Pisces 1 design is in providing a carefully specified virtual machine that defines the run-time environment within which Pisces FORTRAN programs are executed. Each implementation then provides the same virtual machine, regardless of differences in the underlying architecture. The design is intended to be portable to a variety of architectures. Currently Pisces 1 is implemented on a network of Apollo workstations and on a DEC VAX uniprocessor via simulation of the task level parallelism. An implementation for the Flexible Computing Corp. FLEX/32 is under construction. An introduction to the Pisces 1 virtual computer and the FORTRAN 77 extensions is presented. An example of an algorithm for the iterative solution of a system of equations is given. The most notable features of the design are the provision for several granularities of parallelism in programs and the provision of a window mechanism for distributed access to large arrays of data.

Pratt, T. W.↗
NASA NTRS2002

COLLIDE-2: Collisions Into Dust Experiment-2

The Collisions Into Dust Experimental (COLLIDE-2) was the second flight of the COLLIDE payload. The payload performs six low-velocity impact experiments to study the collisions that are prevalent in planetary ring systems and in the early stages of planet formation. Each impact experiment is into a target of granular material, and the impacts occur at speeds between 1 and 100 cm/s in microgravity and in a vacuum. The experiments are recorded on digital videotape which is later analyzed. During the period of performance a plan was developed to address some of the technical issues that prevented the first flight of COLLIDE from being a complete success, and also to maximize the scientific return based on the science results from the first flight. The experiment was modified following a series of reviews of the design plan, and underwent extensive testing. The data from the experiment show that the primary goal of identifying transition regimes for low-velocity impacts based on cratering versus accretion was achieved. Following a brief period of storage, the experiment flew regimes for low-velocity impacts based on cratering versus accretion was achieved. as a Hitchhiker payload on the MACH-1 Hitchhiker bridge on STS-108 in December 2001. These data have been analyzed and submitted for publication. That manuscript is attached to this report. The experiment was retrieved in January 2002, and all six impact experiments functioned nominally. Preliminary results were reported at the Lunar and Planetary Science Conference.

Colwell, Joshua E.↗
DOE OSTI2021

Reusability First: Toward FAIR Workflows

The FAIR principles of open science (Findable, Accessible, Interoperable, and Reusable) have had transformative effects on modern large-scale computational science. In particular, they have encouraged more open access to and use of data, an important consideration as collaboration among teams of researchers accelerates and the use of workflows by those teams to solve problems increases. How best to apply the FAIR principles to workflows themselves, and software more generally, is not yet well understood. We argue that the software engineering concept of technical debt management provides a useful guide for application of those principles to workflows, and in particular that it implies reusability should be considered as ‘first among equals’. Moreover, our approach recognizes a continuum of reusability where we can make explicit and selectable the tradeoffs required in workflows for both their users and developers.To this end, we propose a new abstraction approach for reusable workflows, with demonstrations for both synthetic workloads and real-world computational biology workflows. Through application of novel systems and tools that are based on this abstraction, these experimental workflows are refactored to rightsize the granularity of workflow components to efficiently fill the gap between end-user simplicity and general customizability. Our work makes it easier to selectively reason about and automate the connections between trade-offs across user and developer concerns when exposing degrees of freedom for reuse. Additionally, by exposing fine-grained reusability abstractions we enable performance optimizations, as we demonstrate on both institutional-scale and leadership-class HPC resources.

Wolf, Matthew↗
NASA NTRS1990

Effects of grain size and grain boundary on critical current density of high T(sub c) superconducting oxides

By means of adding impurity elements in high T sub c oxides, the effects were studied of grain size and grain boundary on the critical current density of the following systems: YBa2Cu3O(7-y) and Bi-Pr-Sr-Ca-Cu-O. In order to only change the microstructure instead of the superconductivity of the grains in the samples, the impurity elements were added into the systems in terms of the methods like this: (1) substituting Y with the lanthanide except Pr, Ce, and Tb in YBa2Cu3O(7-y) system to finning down grains in the samples, therefore, the effect can be investigated of the grain size on the critical current density of 1:2:3 compounds; (2) mixing the high T sub c oxides with the metal elements, such as Ag, according to the composition of (high T sub c oxide)1-xAgx to metallize the grain boundaries in the samples, studying the effect of the electric conductivity of the grain boundaries on the critical current density; (3) adding SiO2, PbO2, and SnO2 into the high T sub c oxide to form impurity phases in the grain boundaries, trying to find out the effects of the impurity phases or metalloid grain boundaries on the critical current density of the high T sub c superconductors. The experimental results indicate that in the case of of the presence of the metalloid grain boundaries finning down grains fails to enhance the j sub c, but restrains it strongly, the granular high T sub c superconductors with the small size grains coupled weakly is always the low j sub c system.

Zhao, Y.↗
DOE OSTI2020

New self-consistent homogenization for thermo-elastic polycrystals with imperfect interfaces

Here we present a new thermo-elastic self-consistent formulation to calculate the thermo-mechanical response of polycrystalline aggregates with imperfect interfaces. The new model is based on an improved treatment of the effect of imperfect interfaces on the micromechanical response of the grains compared to pre-existing models. New expressions/algorithms are derived for the effective elastic and thermal properties, localization relations, and calculation of intragranular field fluctuations. In addition, derivation of a novel integral equation for the strain field in a heterogeneous elastic medium subjected to arbitrary thermal strain field and displacement jumps is presented. The new model is applied to study the effective thermo-elastic properties and average field fluctuations as a function of the interface properties for imperfectly-bonded triaminotrinitrobenzene (TATB) polycrystalline granular aggregates. The proposed formulation is general in the sense that it can be extended to other material systems and deformation regimes that require a proper consideration of the effect of imperfect interface properties on the material's thermo-mechanical response.

36 MATERIALS SCIENCE↗
DOE OSTI2022

Response of a CMS HGCAL silicon-pad electromagnetic calorimeter prototype to 20–300 GeV positrons

The Compact Muon Solenoid collaboration is designing a new high-granularity endcap calorimeter, HGCAL, to be installed later this decade. As part of this development work, a prototype system was built, with an electromagnetic section consisting of 14 double-sided structures, providing 28 sampling layers. Each sampling layer has an hexagonal module, where a multipad large-area silicon sensor is glued between an electronics circuit board and a metal baseplate. The sensor pads of approximately 1.1 cm$^{2}$ are wire-bonded to the circuit board and are readout by custom integrated circuits. The prototype was extensively tested with beams at CERN's Super Proton Synchrotron in 2018. Based on the data collected with beams of positrons, with energies ranging from 20 to 300 GeV, measurements of the energy resolution and linearity, the position and angular resolutions, and the shower shapes are presented and compared to a detailed Geant4 simulation.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2024

RANGERS: Methodology Report on Design and Performance Assessment of Engineered Barrier Systems in a Salt Repository for HLW/SNF

Salt formations are one of the potential host rocks for the final disposal of high-level radioactive waste (HLW) in deep geological repositories, both in Germany and the United States. The safe isolation of radioactive waste in these repositories relies on a multi-barrier system, combining engineered and natural barriers. The natural barrier is provided by the salt rock itself, known for its self-sealing properties and long-term stability. The engineered barrier, on the other hand, comprises sealing components strategically placed within the repository to enhance its containment capabilities. In both Germany and the United States, long-term safety assessments require demonstrating the integrity of the natural barrier for a period of up to 1 million years. Concurrently, the engineered barrier system (EBS) must maintain its structural and functional integrity until the long-term sealing, such as the granular salt backfill material, has re-consolidated to its final low porosity and permeability. Based on extensive expertise and experience with engineered barriers in salt formations, BGE TECHNOLOGY GmbH and Sandia National Laboratories have partnered to develop a robust methodology for the integrity and performance assessment of EBS in HLW repositories through the RANGERS project. This collaborative effort aims to establish a unified approach to geotechnical engineering, repository design, integrity and performance evaluation of EBS in salt repositories.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
NASA NTRS1993

The theory of interface slicing

Interface slicing is a new tool which was developed to facilitate reuse-based software engineering, by addressing the following problems, needs, and issues: (1) size of systems incorporating reused modules; (2) knowledge requirements for program modification; (3) program understanding for reverse engineering; (4) module granularity and domain management; and (5) time and space complexity of conventional slicing. The definition of a form of static program analysis called interface slicing is addressed.

Beck, Jon↗
NASA NTRS1996

Capillary Movement in Substrates in Microgravity

A more complete understanding of the dynamics of capillary flow through an unsaturated porous medium would be useful for a number of space and terrestrial applications. Knowledge of capillary migration of liquids in granular beds in microgravity would significantly enhance the development and understanding of how a matrix based nutrient delivery system for the growth of plants would function in a microgravity environment. Thus, such information is of interest from the theoretical as well as practical point of view.

Bula, R. J.↗