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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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Space-based Measurements of Neutron Lifetime: A Novel Approach to a Long-standing Problem
Free neutrons decay via the weak interaction with a mean lifetime of around 15 minutes. Knowledge of this lifetime is important as it provides constraints on the unitarity of the CKM matrix and is a key parameter for studies of Big-Bang nucleosynthesis. However, current laboratory measurements differ by as much as 5σ. We are investigating a new technique to measure neutron lifetime: space-based neutron spectroscopy. We will complete a proof-of-principle demonstration using data from NASA’s MESSENGER mission to Mercury.
Conceptual design for a blanket tritium extraction test stand
Tritium breeding is fundamentally required for a sustainable fusion fuel cycle, yet the technological readiness of blanket technology lags far behind other fusion systems. Breeder concepts are divided into solid and liquid media, where solid breeders typically rely on a sweep gas, such as helium, to carry away tritium from lithium containing ceramic materials, and liquid breeders produce tritium from lithium containing eutectics (e.g., PbLi) or molten salts (FLiBe). In each case, tritium must be harvested from the breeding medium. A promising method for tritium extraction is through a vacuum permeator, in which a concentration gradient from the tritium- containing fluid promotes diffusion through a membrane with high hydrogen permeability to the vacuum. This technology has been demonstrated for hydrogen gas systems using Pd and PdAg permeators, but relatively little work has been done to test tritium extraction from PbLi. A Tritium Extraction eXperimental (TEX) loop is being designed to test tritium extraction in a vacuum permeator configuration. The system design is such that it will allow the testing of tritium extraction from both helium and PbLi. A phased approach is being taken that will allow testing of small specimens for fundamental permeation measurements, to multi-meter component testing at near-prototypic conditions. A molten PbLi loop is challenging due to the toxic and explosive nature of Pb and Li, respectively, radiological concerns by introducing tritium, and high temperatures involved in such a system. In addition, PbLi corrosion is a significant issue at high temperatures (>400C). The TEX system will not employ a neutron source for volumetric production of tritium. Herein we present the design and methods used for 1) pumping PbLi, 2) introducing deuterium or tritium into the PbLi, 3) quantifying the amount of deuterium in the loop, 4) extracting deuterium and tritium, and 5) quantifying the total amount of extracted deuterium or tritium from the permeator. In addition, the safety design for operating such a system will be discussed.
Commissioning of the Low Energy Electron Gun Test Stand at the University of Chicago
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NuMI Hadron Monitor – Calibration Stand
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High Enthalpy Differential Equation-Based Estimates for Spherical/Cylindrical Forebody Shock Stand-off Distance .
Abstract not provided.
TinyTPC: A Test Stand for LAr Doping
TinyTPC is a small scale liquid-argon time projection chamber (LArTPC) featuring a pixelated readout system (LArPix) designed to improve the detection of charged particles. To enhance energy measurements at MeV scales, TinyTPC will study the impact of isobutylene, a photosensitive dopant that converts light to charge, and xenon, a wavelength shifter. This presentation will detail TinyTPC's commissioning, operation, data collection methodologies, noise levels, and upcoming tests involving isobutylene, xenon, and radioactive sources.
TinyTPC: A Test Stand for LAr Doping
LArTPCs are widely used in neutrino experiments at the GeV scale. They measure the charge and light produced by interactions between charged particles and argon atoms. While charge is collected efficiently, light is not. TinyTPC is a small scale LArTPC with a pixelated readout for R&D with photosensitive dopants, which convert light into charge. TinyTPC studies the effects of adding photosensitive dopants and xenon to liquid argon to enhance charge signals of events in the MeV scale.
Enabling Outdoor Stand-Off Radiation Detection via Calibrated Fluorescence Spectrum
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Exploring the Great Pyramid: Detector Technical Design Report with Stand-Alone Monte Carlo Simulations
Cosmic-ray muon imaging has been used to non-destructively examine the Pyramids of Khufu and Khafre on the Giza Plateau; the EGP project will continue this line of research by undertaking a full tomographic scan of the former and by doing so will increase the sensitivity of the technique by upwards of two orders of magnitude. For this purpose, a muon telescope using triangular (vernier) detector cells far outperforms one with rectangular cells, providing an angular and positional RMS improvement by a factor of 4 for the same cost per unit area. A refinement algorithm was developed to handle tracks that produce secondaries. The triangular detector yields a positional resolution for a back-projection to the center of the pyramid of less than 20 cm, ensuring that a feature large enough to be of significance will still be seen by the telescope. This method is shown to be able to accurately and precisely reconstruct tracks of muons that pass through the King s Chamber, Queen s Chamber, and Grand Gallery.
Optimization of the artificial viscosity in Lagrangian staggered discretization codes. Modeling 1D stand-alone shock - case study
We have developed new measures of errors for numerical shock. The new approach is based on analysis of the structure function, and separation of the errors related to oscillations and shock width, which also include error in the position of the ”center” of the numerical shock. We have demonstrated that those measures correctly characterize the numerical solution. We introduced an objective function in, which both types of errors are weighted, and presented optimal values of the coefficients of the linear and quadratic viscosity for different weights and different Mach numbers.
Short-Baseline anomalies and sterile neutrinos: Where we stand and where were going
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How to Model Batteries (with PV, Stand-Alone, or Hybrids) in SAM and PySAM
This tutorial will be a deep dive into considerations for battery modeling and demonstrating how to model them in SAM, including battery chemistry, thermal modeling, degradation/lifetime, dispatch, interconnection limits and curtailment, and their associated impacts on project profits and battery lifetime. By the end of the tutorial attendees will know how to size and model both behind-the-meter and front-of-meter battery systems, including financial analysis and pairing with other PV models (including pvlib) via PySAM.
Catalytic Fast Pyrolysis Oil Stand-Alone and Co-Hydroprocessing Case Studies: Design, Cost, and Sustainability Based on Process Model Predictions
Refined liquid fuels provide conveniences for road, rail, air, and marine transportation due to high energy density, ease of transport and storage, and existing production and distribution infrastructure. Biomass conversion technologies can help diversify and increase the supply of liquid fuels towards a more robust energy future. The backbone of such development must include reliable, high-volume biomass supply chains and efficient utilization of those resources. These activities, if pursued, will lead to rural infrastructure development and new jobs.
Conductivity and Vacuum Flashover Measurements on Composite Materials using a Pulsed-Power Test Stand
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Development of radiopharmaceuticals for targeted alpha therapy: Where do we stand?
Targeted alpha therapy is an oncological treatment, where cytotoxic doses of alpha radiation are locally delivered to tumor cells, while the surrounding healthy tissue is minimally affected. This therapeutic strategy relies on radiopharmaceuticals made of medically relevant radionuclides chelated by ligands, and conjugated to targeting vectors, which promote the drug accumulation in tumor sites. This review discusses the state-of-the-art in the development of radiopharmaceuticals for targeted alpha therapy, breaking down their key structural components, such as radioisotope, targeting vector, and delivery formulation, and analyzing their pros and cons. Moreover, we discuss current drawbacks that are holding back targeted alpha therapy in the clinic, and identify ongoing strategies in field to overcome those issues, including radioisotope encapsulation in nanoformulations to prevent the release of the daughters. Lastly, we critically discuss potential opportunities the field holds, which may contribute to targeted alpha therapy becoming a gold standard treatment in oncology in the future.
Reassessing long-standing meteorological records: an example using the national hottest day in Ireland
This analysis highlights the potential value in reanalysing early national meteorological records from around the world. These were oftentimes measured via techniques that preceded standardisation of instrumentation and methods of observation and thus could be subject to considerable biases and uncertainties. This analysis uses the techniques pioneered by WMO record assessment teams. The highest currently recognised air temperature (33.3 °C) ever recorded in the Republic of Ireland was logged at Kilkenny Castle in 1887. The original observational record however no longer exists. Given that Ireland is now the only country in Europe to have a national heat record that was set in the 19th century, a reassessment of the verity of this record is both timely and valuable. The present analysis undertakes a fundamental reassessment of the plausibility of the 1887 temperature record using methods similar to those used to assess various weather extremes under WMO auspices over recent years. Specifically, we undertake an inter-station reassessment using sparse available records and make recourse to the new and improved 20CRv3 sparse-input reanalysis product. Neither surrounding available stations nor the reanalysis offer substantive support for the Kilkenny record of 33.3 °C being correct. Moreover, recent data rescue efforts have uncovered several earlier extreme values, one of which exceeds the Kilkenny value (33.5 °C on 16 July 1876 recorded at the Phoenix Park). However, the sparsity of early observational networks, a distinct lack of synoptic support from 20CRv3 for many of the extreme heat values, and the fact that these measurements were obtained using non-standard exposures lead us to conclude that there is grossly insufficient evidence to support any of these 19th century extremes as robust national heat record candidates. Data from the early 20th century onwards benefit from a denser network of stations undertaking measurements in a more standardised manner, many under the direct auspices of Met Éireann and its predecessors, adhering to WMO guidance and protocols. This enables more robust cross-checking of records. We argue that the Met Éireann-recognised 20th century heat record from Boora in 1976 is verified as the most plausible robust national temperature record based upon the synoptic situation and comparisons with nearby neighbouring stations. This measurement of 32.5°C thus likely constitutes the highest reliably recorded temperature measurement in the Republic of Ireland. Ultimately, the formal decision on any reassessment and reassignment of the national record rests with the national meteorological service, Met Éireann.
Design of RUSL Irradiation Experiment with Free Standing Sample
During FY19, the MIMIC-RUSL TREAT test successfully measured the shift in resonance of a cantilever beam as it underwent a grain restructuring event in the TREAT reactor core. FY20 efforts focused on a new capsule design which would replace the cantilever beam with a free-free beam. The free-free beam configuration eliminates the cantilever boundary condition and enables internal friction measurements. A test capsule was designed which supported the sample beam at the nodal points of the first flexural vibration mode. Initial tests detected the resonance peak but the signal to noise level was not high enough for in-situ measurements. Several detection probes were tested and a significant increase in the signal to noise was achieved. Although adequate signals and clean resonance peaks were measured when the beam was centered, the beam did not self-center when displaced resulting in distorted and inconsistent resonance peaks. It was concluded that the free-free beam approach is likely not suited for in-situ measurements. Measurement of ZGV plate waves is another option for in-situ microstructure monitoring and should be considered for future work.