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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 397 records · Page 22
All sourcesNASA NTRSDOE OSTI
DOE OSTI2022

Volumetric nondestructive evaluation for damage in carbon fiber reinforced polymer panels subjected to artificial lightning strikes

Aircrafts and wind turbine blades often get hit by lightning strikes due to their operating locations. With increasing incidents of lightning flashes every year due to global warming, damage assessment of CFRP structures after lightning strike to aircrafts and wind turbine blades is getting increasingly important. Many researchers are involved in designing better and more resilient lighting strike protection materials and often utilize non-destructuve evaluation (NDE) methods such as ultrasonic testing (UT), high-speed digital videograpgy, and high-speed IR thermography. In particular, UT is widely used due to its cost-effectiveness compared to other methods. Using UT imaging can obtain any potential damaged locations caused by lightning strike through the thickness of the composite specimens. Traditional UT and visual inspections only display the damage in units area, when in fact the UT data is volumetric. This study optimized the UT data to measure and display the volumetric damage after artificial lightning strike and is compared to the standardized visual inspection.

Spencer, Ryan↗
DOE OSTI2019

{sup 18}F-sodium fluoride positron emission tomography assessed microcalcifications in culprit and non-culprit human carotid plaques

Background: {sup 18}F-NaF positron emission tomography (PET) targets microcalcifications. We compared in vitro microPET assessed {sup 18}F-NaF uptake between culprit and non-culprit human carotid plaques. Furthermore, we compared {sup 18}F-NaF uptake with calcification visualized on microcomputed tomography (microCT). Methods: Carotid plaques from stroke patients undergoing surgery were incubated in {sup 18}F-NaF and scanned using a microPET and a microCT scan. The average PET assessed {sup 18}F-NaF uptake was expressed as percentage of the incubation dose per gram (%Inc/g). {sup 18}F-NaF PET volume of interest (VOI) was compared with CT calcification VOI. Results: 23 carotid plaques (17 culprit, 6 non-culprit) were included. The average {sup 18}F-NaF uptake in culprit carotid plaques was comparable with the uptake in non-culprit carotid plaques (median 2.32 %Inc/g [IQR 1.98 to 2.81] vs. median 2.35 %Inc/g [IQR 1.77 to 3.00], P = 0.916). Only a median of 10% (IQR 4 to 25) of CT calcification VOI showed increased {sup 18}F-NaF uptake, while merely a median of 35% (IQR 6 to 42) of {sup 18}F-NaF PET VOI showed calcification on CT. Conclusions: {sup 18}F-NaF PET represents a different stage in the calcification process than CT. We observed a similar PET assessed {sup 18}F-NaF uptake and pattern in culprit and non-culprit plaques of high-risk patients, indicating that this method may be of more value in early atherosclerotic stenosis development. [French] French Abstract: Contexte: La tomographie par émission de positons (TEP) au {sup 18}F-NaF marque les micro-calcifications. Nous avons comparé in vitro les plaques carotidiennes humaines responsable d’accident vasculaire cérébrales marquées au {sup 18}F-NaF avec une microTEP et leur calcification au moyen d’un microCT Méthodes: Les plaques carotidiennes de patients victimes d’un accident vasculaire cérébral qui ont bénéficié d’ une intervention chirurgicale ont été incubées dans du {sup 18}F-NaF et imagées avec une microTEP et un microCT. Le pourcentage d’absorption moyen de {sup 18}F-NaF par gr de tissu (% Inc/g) ont été comparées au volume d’intérêt (VOI) des calcifications mesurées par CT. Résultats: 23 plaques carotidiennes (17 responsables d’un AVC et 6 non responsables) ont été incluses. Le % moyen d’absorption de {sup 18}F-NaF dans les plaques carotidiennes responsables furent comparable à l’absorption dans les plaques non responsables (2,32% Inc/g vs 2,35% Inc/g , p = 0,916). Dix pourcent seulement des calcifications visualisées par CT démontrèrent une augmentation d’absorption de {sup 18}F-NaF et 35% des plaques montrant une absorption de {sup 18}F-NaF PET VOI démontrèrent des calcifications au CT. Conclusions: L’imagerie de l’absorption de {sup 18}F-NaF par tomographie à positrons représente un processus physiopathologique différent de l’imagerie des calcifications par CT. L’absorption du {sup 18}F-NaF par les plaques responsables et non responsables d’accidents vasculaire cérébraux pourrait s’avérer utile dans le diagnostic précoce des sténoses athéromateuses. [Spanish] Spanish Abstract: Antecedentes: La tomografía por emisión de positrones (PET) con {sup 18}F-floruro de sodio ({sup 18}F-NaF) demuestra microcalcificaciones. En este estudio, comparamos la captación de {sup 18}F-NaF entre placas carotideas culpables y no culpables valorada con microPET in vitro. Además, comparamos la captación de {sup 18}F-NAF con las calcificaciones detectadas por microtomografía computada (microCT). Métodos: Placas carotídeas de pacientes postoperados que sufrieron de un evento vascular cerebral fueron incubadas en 18-NaF y escaneadas usando microPET y microCT. El promedio de la captación fue expresado como porcentaje de la dosis de incubación por gramo (%Inc/gr). El volumen de interés (VOI) del PET {sup 18}F-NaF se comparó con el VOI de calcificación por CT. Resultados: Se incluyeron 23 placas carotídeas (17 culpables y 6 no culpables). El promedio de la captación de {sup 18}F-NaF en placas carotídeas culpable fue comparable al de las placas no culpables. (mediana 2.32%Inc/gr [IQR1.98-2.81] vs. mediana 2.35%Inc/gr [IQR1.77-3], p=.916). Solo una mediana de 10% (IQR 4-25) del VOI en CT mostró un aumento en la captación de {sup 18}F-NaF, mientras una mediana de 35% (IQR 6-42) del VOI de PET {sup 18}F-NaF mostró calcificación en CT. Conclusiones: La tomografía por emisión de positrones con {sup 18}F-NaF evalúa una etapa distinta en el proceso de calcificación que la CT. El patrón de captación de {sup 18}F-NaF que observamos en este estudio fue similar entre placas culpables y no culpables de pacientes de alto riesgo, lo cual indica que este método puede ser de mayor valor en el desarrollo temprano de la estenosis ateroesclerótica. [Chinese] Chinese Abstract: 背景: F18 氟化钠正电子发射断层扫描 (PET) 可用于检测微钙化。我们使用微型 PET 来评估病人体外 F18 氟化钠在颈动脉罪犯和非罪犯斑块之间的的摄取区别。此外, 我们还将 F18 氟化钠的摄取与 microCT 扫描检测的钙化进行对比。 方法: 将接受手术的中风患者的颈动脉斑块在 F18 氟化钠中培养并用 microPE 和 microCT 进行扫描。PET 对 F18 氟化钠的平均摄取率表示为每克培养剂量的百分比。F18 氟化钠 PET 中的感兴趣区域和 CT 钙化图像中的感兴趣区域 (VOI) 进行比较。 结果: 一共有 23个颈动脉斑块, 其中 17个罪犯斑块和 6个非罪犯斑块。罪犯和非罪犯颈动脉斑块的 F18 氟化钠的平均摄取率无明显差异 (中值 2.32 % Inc/g [IQR 1.98-2.81] vs. 中值2.35 % Inc/g [IQR 1.77-3.00], p = 0.916)。仅中值为10% [IQR 4-25] 的 CT 钙化 VOI 显示有F18氟化钠的摄取增加, 中值为 35%[IQR 6-42] 的 F18 氟化钠 PET VOI 显示有CT 上的钙化。 结论: 相较于 CT, F18 氟化钠 PET 展现了钙化过程中的一个不同阶段。在高危病人中, 我们观察到罪犯和非罪犯斑块具有类似的 PET F18 氟化钠摄取和模式, 表明该方法可能在早期动脉粥样硬化狭窄发展中具有更高的价值。.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
NASA NTRS1979

Infrared observations of the X-ray quasars 0241+622 and MR2251-178

Infrared observations of the recently discovered X-ray quasars 0241+622 and MR2251-178 are reported. Broadband photometry of both quasars was conducted in the 1.25 to 20 micron range and spectrophotometry of 0241+622 was carried out from 1.5 to 2.5 microns. The IR energy distributions of 0241+622, MR2251-178 and the X-ray quasar 3C273 are presented, noting that for wavelengths less than 10 microns, the energy distributions of all three quasars are similar and cannot be distinguished from those of other low redshift quasars. The observed IR, visual and X-ray luminosities of the three quasars are compared and are found not to be strongly correlated. It is remarked, however, that the three X-ray quasars are the brightest known quasars at IR and visual wavelengths, which supports the suggestion that all quasars are bright X-ray emitters.

Soifer, B. T.↗
DOE OSTI2025

Ensemble‐Based, Large‐Eddy Reconstruction of Wind Turbine Inflow in a Near‐Stationary Atmospheric Boundary Layer Through Generative Artificial Intelligence

ABSTRACT To validate the second‐by‐second dynamics of turbines in field experiments, it is necessary to accurately reconstruct the winds going into the turbine. Current time‐resolved inflow reconstruction techniques estimate wind behavior in unobserved regions using relatively simple spectral‐based models of the atmosphere. Here, we develop a technique for time‐resolved inflow reconstruction that is rooted in a large‐eddy simulation model of the atmosphere. Our “large‐eddy reconstruction” technique blends observations and atmospheric model information through a diffusion model machine learning algorithm, allowing us to generate probabilistic ensembles of reconstructions for a single 10‐min observational period. Our generated inflows can be used directly by aeroelastic codes or as inflow boundary conditions in a large‐eddy simulation. We verify the second‐by‐second reconstruction capability of our technique in three synthetic field campaigns, finding positive Pearson correlation coefficient values () between ground‐truth and reconstructed streamwise velocity, as well as smaller positive correlation coefficient values for unobserved fields (spanwise velocity, vertical velocity, and temperature). We validate our technique in three real‐world case studies by driving large‐eddy simulations with reconstructed inflows and comparing to independent inflow measurements. The reconstructions are visually similar to measurements, follow desired power spectra properties, and track second‐by‐second behavior ().

17 WIND ENERGY↗
DOE OSTI2019

Pain in percutaneous liver core-needle biopsy: a randomized trial comparing the intercostal and subcostal approaches

Purpose: Effective pain control during and after percutaneous core needle liver biopsy is important with regard to ethical considerations and patient comfort. In this randomized double-blind study, we compared post-biopsy pain in the patients undergoing liver core-needle biopsy using either subcostal or intercostal approaches. Methods: All patients referred for ultrasound-guided CNLB between July 2017 and January 2018 to our interventional radiology department were randomized into two groups. Biopsy was performed through intercostal approach in the first group and through subcostal approach in the second group. The intensity of pain 0, 2, and 4 h after the procedure was compared in two groups using a 100-mm visual analogue scale. All biopsies were performed without procedural IV sedation. If patients’ discomfort demanded administration of IV analgesics during or after the procedure, then the patients were excluded from the study. Results: In patients without routine procedural IV sedation, there was no significant difference in the pain level between the intercostal and subcostal groups immediately after the procedure (p = 0.055), but we found a significant difference in the pain level between the two groups 2 (7.5 mm, p = 0.001) and 4 (2 mm, p = 0.001) h after the procedure. Conclusion: The minimum amount of change in the VAS score that is considered clinically important is 13 mm on a 100-mm scale. Pain differences at 2 and 4 h in the two groups in this study were statistically but not clinically significant. Therefore, the authors suggest the use of subcostal route for ultrasound-guided liver biopsy whenever possible, but the results do not warrant the routine use of post-procedure analgesics in whom biopsy is performed via intercostal route.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2018

Using ChemCam LIBS data to constrain grain size in rocks on Mars: Proof of concept and application to rocks at Yellowknife Bay and Pahrump Hills, Gale crater

Grain size in martian sedimentary rocks can be constrained using point-to-point chemical variabilities in Laser Induced Breakdown Spectroscopy (LIBS) data from the ChemCam instrument on the Mars Science Laboratory (MSL) Curiosity rover. The diameter of each point ablated by the ChemCam laser is in the range of medium to coarse sand in size. Thus, rocks with grains significantly smaller than the laser spot size produce bulk rock compositions at each LIBS point and low point-to-point chemical variability among LIBS points. In contrast, analyses of rocks with grains about the size of the spot or larger contain contributions from individual grains at each point and often have high point-to-point chemical variability. Here the Gini index, a statistical parameter, was used to calculate the point-to-point chemical variability in major-element oxide compositions derived from the ChemCam LIBS data. First, the total range of each LIBS major-element oxide composition was normalized from 0 to 1 across all LIBS observations. Then the Gini index was calculated for each oxide in each LIBS observation. Finally, the Gini indices of each oxide were averaged to derive a Gini index mean score, G MEAN , for each LIBS observation. A correlation between G MEAN and grain size was validated using sedimentary rocks of various grain sizes from the Yellowknife Bay formation and the Pahrump Hills member of the Murray formation in Gale crater. Overall, finer-grained rocks had smaller G MEAN than coarser-grained rocks. To calibrate G MEAN to grain size, grain size estimates based on visual assessment of high-resolution images were compared to G MEAN values for the same targets to create a calibrated scale. This calibrated scale was used to infer the grain size of rocks with unknown grain size. Overall, the grain sizes predicted for rocks with unknown grain size overlapped with those of known grain size from the same units and/or bedrock targets. The grain sizes inferred using the G MEAN based on ChemCam LIBS data are complimentary to those determined from images and both techniques can be used to improve interpretations of the depositional environments of rocks analyzed by Curiosity and future Mars missions with LIBS, such as the Mars 2020 rover.

58 GEOSCIENCES↗
DOE OSTI2014

Fish Passage though Hydropower Turbines: Simulating Blade Strike using the Discrete Element Method

mong the hazardous hydraulic conditions affecting anadromous and resident fish during their passage though turbine flows, two are believed to cause considerable injury and mortality: collision on moving blades and decompression. Several methods are currently available to evaluate these stressors in installed turbines, i.e. using live fish or autonomous sensor devices, and in reduced-scale physical models, i.e. registering collisions from plastic beads. However, a priori estimates with computational modeling approaches applied early in the process of turbine design can facilitate the development of fish-friendly turbines. In the present study, we evaluated the frequency of blade strike and nadir pressure environment by modeling potential fish trajectories with the Discrete Element Method (DEM) applied to fish-like composite particles. In the DEM approach, particles are subjected to realistic hydraulic conditions simulated with computational fluid dynamics (CFD), and particle-structure interactions—representing fish collisions with turbine blades—are explicitly recorded and accounted for in the calculation of particle trajectories. We conducted transient CFD simulations by setting the runner in motion and allowing for better turbulence resolution, a modeling improvement over the conventional practice of simulating the system in steady state which was also done here. While both schemes yielded comparable bulk hydraulic performance, transient conditions exhibited a visual improvement in describing flow variability. We released streamtraces (steady flow solution) and DEM particles (transient solution) at the same location from where sensor fish (SF) have been released in field studies of the modeled turbine unit. The streamtrace-based results showed a better agreement with SF data than the DEM-based nadir pressures did because the former accounted for the turbulent dispersion at the intake but the latter did not. However, the DEM-based strike frequency is more representative of blade-strike probability than the steady solution is, mainly because DEM particles accounted for the full fish length, thus resolving (instead of modeling) the collision event.

CFD↗
DOE OSTI2019

Finding high-redshift strong lenses in DES using convolutional neural networks

We search Dark Energy Survey (DES) Year 3 imaging data for galaxy-galaxy strong gravitational lenses using convolutional neural networks. We generate 250 000 simulated lenses at redshifts > 0.8 from which we create a data set for training the neural networks with realistic seeing, sky and shot noise. Using the simulations as a guide, we build a catalogue of 1.1 million DES sources with 1.8 < g - i < 5, 0.6 < g - r < 3, r_mag > 19, g_mag > 20, and i_mag > 18.2. We train two ensembles of neural networks on training sets consisting of simulated lenses, simulated non-lenses, and real sources. We use the neural networks to score images of each of the sources in our catalogue with a value from 0 to 1, and select those with scores greater than a chosen threshold for visual inspection, resulting in a candidate set of 7301 galaxies. During visual inspection, we rate 84 as 'probably' or 'definitely' lenses. Four of these are previously known lenses or lens candidates. We inspect a further 9428 candidates with a different score threshold, and identify four new candidates. We present 84 new strong lens candidates, selected after a few hours of visual inspection by astronomers. This catalogue contains a comparable number of high-redshift lenses to that predicted by simulations. Based on simulations, we estimate our sample to contain most discoverable lenses in this imaging and at this redshift range.

Jacobs, C.↗
DOE OSTI2014

SU-E-I-72: First Experimental Study of On-Board CBCT Imaging Using 2.5MV Beam On a Radiotherapy Linac

Purpose: Varian TrueBeam version 2.0 comes with a new inline 2.5MV beam modality for image guided patient setup. In this work we develop an iterative volumetric image reconstruction technique specific to the beam and investigate the possibility of obtaining metal artifact free CBCT images using the new imaging modality. Methods: An iterative reconstruction algorithm with a sparse representation constraint based on dictionary learning is developed, in which both sparse projection and low dose rate (10 MU/min) are considered. Two CBCT experiments were conducted using the newly available 2.5MV beam on a Varian TrueBeam linac. First, a Rando anthropomorphic head phantom with and without a copper bar inserted in the center was scanned using both 2.5MV and kV (100kVp) beams. In a second experiment, an MRI phantom with many coils was scanned using 2.5MV, 6MV, and kV (100kVp) beams. Imaging dose and the resultant image quality is studied. Results: Qualitative assessment suggests that there were no visually detectable metal artifacts in MV CBCT images, compared with significant metal artifacts in kV CBCT images, especially in the MRI phantom. For a region near the metal object in the head phantom, the 2.5MV CBCT gave a more accurate quantification of the electron density compared with kV CBCT, with a ∼50% reduction in mean HU error. As expected, the contrast between bone and soft-tissue in 2.5MV CBCT decreased compared with kV CBCT. Conclusion: On-board CBCT imaging with the new 2.5MV beam can effectively reduce metal artifacts, although with a reduced softtissue contrast. Combination of kV and MV scanning may lead to metal artifact free CBCT images with uncompromised soft-tissue contrast.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2020

The weakly nonlinear response and nonaffine interpretation of the Johnson–Segalman/Gordon–Schowalter model

We derive new analytical solutions for the non-affine Johnson-Segalman/Gordon-Schowalter (JS/GS) constitutive equation with a general relaxation kernel in medium-amplitude oscillatory shear (MAOS) deformation. The results show time-strain separable (TSS) nonlinearity, therefore providing new physically-meaningful interpretation to the heuristic TSS nonlinear parameter in MAOS. The upper-convected, lower-convected, and corotational Maxwell models are all subsets of the results presented here. The model assumes that the microscale elements causing stress in the material slip compared to the continuum deformation. We introduce a visualization of the non-affine deformation field that acts on stress-generating elements to reinforce the hysical interpretation of the JS/GS class of models. Lastly, a case study is presented where previously published results, from fitting TSS models to MAOS data, can be re-interpreted based on the concept of non-affine motion of the JS/GS framework.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Exploring the Interaction Between Head-Supported Mass, Posture, and Visual Stress on Neck Muscle Activation

Objective Assess neck muscle activity for varying interactions between helmet, posture, and visual stress in a simulated “helo-hunch” posture. Background Military aviators frequently report neck pain (NP). Risk factors for NP include head-supported mass, awkward postures, and mental workload. Interactions between these factors could induce constant low-level muscle activation during helicopter flight and better explain instances of NP. Method Interactions between physical loading (helmet doffed/donned), posture (symmetric/asymmetric), and visual stress (low/high contrast) were studied through neck muscle electromyography (EMG), head kinematics, subjective discomfort, perceived workload, and task performance. Subjects ( n = 16) performed eight 30-min test conditions (varied physical loading, posture, and visual stress) while performing a simple task in a simulated “helo-hunch” seating environment. Results Conditions with a helmet donned had fewer EMG median frequency cycles (which infer motor unit rotation for rest/recovery, where more cycles are better) in the left cervical extensor and left sternocleidomastoid. Asymmetric posture (to the right) resulted in higher normalized EMG activity in the right cervical extensor and left sternocleidomastoid and resulted in less lateral bending compared with neutral across all conditions. Conditions with high visual stress also resulted in fewer EMG cycles in the right cervical extensor. Conclusion A complex interaction exists between the physical load of the helmet, postural stress from awkward postures, and visual stress within a simulated “helo-hunch” seating environment. Application These results provide insight into how visual factors influence biomechanical loading. Such insights may assist future studies in designing short-term administrative controls and long-term engineering controls.

Behavioral Sciences↗
DOE OSTI2015

Elviz – exploration of metagenome assemblies with an interactive visualization tool

Metagenomics, the sequencing of DNA collected from an entire microbial community, enables the study of natural microbial consortia in their native habitats. Metagenomics studies produce huge volumes of data, including both the sequences themselves and metadata describing their abundance, assembly, predicted functional characteristics and environmental parameters. The ability to explore these data visually is critically important to meaningful biological interpretation. Current genomics applications cannot effectively integrate sequence data, assembly metadata, and annotation to support both genome and community-level inquiry. Elviz (Environmental Laboratory Visualization) is an interactive web-based tool for the visual exploration of assembled metagenomes and their complex metadata. Elviz allows scientists to navigate metagenome assemblies across multiple dimensions and scales, plotting parameters such as GC content, relative abundance, phylogenetic affiliation and assembled contig length. Furthermore Elviz enables interactive exploration using real-time plot navigation, search, filters, axis selection, and the ability to drill from a whole-community profile down to individual gene annotations. Thus scientists engage in a rapid feedback loop of visual pattern identification, hypothesis generation, and hypothesis testing. Compared to the current alternative of generating a succession of static figures, Elviz can greatly accelerate the speed of metagenome analysis. Elviz can be used to explore both user-submitted datasets and numerous metagenome studies publicly available at the Joint Genome Institute (JGI). Elviz is freely available at http://genome.jgi.doe.gov/viz and runs on most current web-browsers.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2014

Sample Results from MCU Solids Outage

Savannah River National Laboratory (SRNL) has received several solid and liquid samples from MCU in an effort to understand and recover from the system outage starting on April 6, 2014. SRNL concludes that the presence of solids in the Salt Solution Feed Tank (SSFT) is the likely root cause for the outage, based upon the following discoveries: A solids sample from the extraction contactor #1 proved to be mostly sodium oxalate; A solids sample from the scrub contactor#1 proved to be mostly sodium oxalate; A solids sample from the Salt Solution Feed Tank (SSFT) proved to be mostly sodium oxalate; An archived sample from Tank 49H taken last year was shown to contain a fine precipitate of sodium oxalate; A solids sample from ; A liquid sample from the SSFT was shown to have elevated levels of oxalate anion compared to the expected concentration in the feed. Visual inspection of the SSFT indicated the presence of precipitated or transferred solids, which were likely also in the Salt Solution Receipt Tank (SSRT). The presence of the solids coupled with agitation performed to maintain feed temperature resulted in oxalate solids migration through the MCU system and caused hydraulic issues that resulted in unplanned phase carryover from the extraction into the scrub, and ultimately the strip contactors. Not only did this carryover result in the Strip Effluent (SE) being pushed out of waste acceptance specification, but it resulted in the deposition of solids into several of the contactors. At the same time, extensive deposits of aluminosilicates were found in the drain tube in the extraction contactor #1. However it is not known at this time how the aluminosilicate solids are related to the oxalate solids. The solids were successfully cleaned out of the MCU system. However, future consideration must be given to the exclusion of oxalate solids into the MCU system. There were 53 recommendations for improving operations recently identified. Some additional considerations or additional details are provided below as recommendations. From this point on, IC-Anions analyses of the DSSHT should be part of the monthly routine analysis in order to spot negative trends in the oxalate leaving the MCU system. Care must be taken to monitor the oxalate content to watch for sudden precipitation of oxalate salts in the system; Conduct a study to optimize the cleaning strategy at ARP-MCU through decreasing the concentration or entirely eliminating the oxalic acid; The contents of the SSFT should remain unagitated. Routine visual observation should be maintained to ensure there is not a large buildup of solids. As water with agitation provided sufficient removal of the solids in the feed tank, it should be considered as a good means for dissolving oxalate solids if they are found in the future; Conduct a study to improve prediction of oxalate solubility in salt batch feed materials. As titanium and mercury have been found in various solids in this report, evaluate if either element plays a role in oxalate solubility during processing; Salt batch characterization focuses primarily on characterization and testing of unaltered Tank 21H material; however, non-typical feeds are developed through cleaning, washing, and/or sump transfers. As these solutions are processed through MCU, they may precipitate solids or reduce performance. Salt batch characterization and testing should be expanded to encompass a broader range of feeds that may be processed through ARPMCU.

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

Lift Equivalence and Cancellation for Airfoil Surge–Pitch–Plunge Oscillations

A NACA 0018 airfoil in freestream velocity is oscillated in longitudinal, transverse, and angle-of-attack directions with respect to the freestream velocity, known as surge, plunge, and pitch. The lift-based equivalence method introduces phase shifts between these three motions to construct in-phase sinusoidal components for maximum lift, waveform construction. Lift cancellation is also determined with the exact negative pitch and plunge motion amplitudes found from the equivalence method to achieve out-of-phase wave destruction. Lift cancellation occurs when a combination of these motions is sought to obtain a constant lift magnitude throughout the oscillation cycle. To achieve both equivalence and cancellation of lift, a prescribed pure pitch amplitude through the Theodorsen theory equates the corresponding equivalent plunge amplitude and pitch–plunge phase shift. These Theodorsen, linear superposition findings of pitch–plunge are leveraged toward the Greenberg theory to determine a closed-form, surge–pitch–plunge solution through the addition of a surge–plunge phase shift and optimal surge amplitude for lift cancellation. The lift cancellation surge–pitch–plunge amplitudes define the equivalence amplitude investigated here and theoretically limit the experiment to combinations of the first lift harmonic of the Greenberg theory. The analytical results are then compared with experimental lift force measurements and dye visualization. Finally, the normalized lift differences due to unsteady wake and boundary-layer behavior are examined to explore the extents of the Greenberg theory for these cases of lift-based equivalence and cancellation.

42 ENGINEERING↗
DOE OSTI2024

Chemical clocks: using otolith geochemistry to enhance estimation of age and growth of white hake (Urophycis tenuis)

The white hake (Urophycis tenuis) is a groundfish distributed throughout the Gulf of Maine. Catch advice is based on stock assessments done with age-based population dynamics models; however, otolith aging is challenging because of unclear growth increments. To address this concern, we compared the consistency of aging with counts of visual annuli to that of aging with cycles of elemental concentrations measured by using laser ablation inductively coupled plasma mass spectrometry. We tested the hypothesis that oscillations in both environmental conditions and internal physiology through time influence uptake of elements during otolith mineralization. Concentrations of manganese, in comparison with those of the other investigated trace elements (magnesium, strontium, and barium), had the most promising correlation with visual growth increments (~100% age agreement, ±1 year), offering an additional tool to enhance increment identification. In our examination of 550 otoliths collected during 2007–2021, we found that white hake lived a maximum of 10.3 years and exhibited sexual dimorphism in maximum length and age. By using generated von Bertalanffy growth functions, L(t)=110(1–e–0.113(t+0.45)) for males and L(t)=140(1–e–0.113(t–0.30)) for females (where L(t) is length at time t), size and age at maturity were calculated for males (37.4 cm in total length (TL), 3.3 years) and females (47.4 cm TL, 4.2 years). These results demonstrate that otolith geochemistry can be used to improve the accuracy and precision of the estimation of fish age and maturity, even for challenging species.

59 BASIC BIOLOGICAL SCIENCES↗
NASA NTRS1977

Effects of film injection angle on turbine vane cooling

Film ejection from discrete holes in the suction surface of a turbine vane was studied for hole axes (1) slanted 30 deg to the surface in the streamwise direction and (2) slanted 30 deg to the surface and 45 deg from the streamwise direction toward the hub. The holes were near the throat area in a five-row staggered array with 8-diameter spacing. Mass flux ratios were as high as 1.2. The data were obtained in an annular sector cascade at conditions where both the ratio of the boundary layer momentum thickness-to-hole diameter and the momentum thickness Reynolds number were typical of an advanced turbofan engine at both takeoff and cruise. Wall temperatures were measured downstream of each of the rows of holes. Results of this study are expressed as a comparison of cooling effectiveness between the in-line angle injection and the compound-angle injection as a function of mass flux ratio. These heat transfer results are also compared with the results of a referenced flow visualization study. Also included is a closed-form analytical solution for temperature within the film cooled wall.

Gauntner, J. W.↗