Search NASA⌕ Search

SEARCH · Search NASA

Results for “Compaction technologies”

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.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,333 records · Page 74

LASER-BASED MEASUREMENT TOOLS FOR FUTURE ENRICHMENT PLANT SAFEGUARDS

The International Atomic Energy Agency (IAEA) has a long history of testing and using laser-based technologies for a variety of safeguards applications. Notable laser-based on-site applications include: 3-dimensional laser range (3DLR) instruments, used for facility design information and verification (DIV); laser measurements to verify unique labels and detect signs of tampering; and laser spectroscopy, for non-contact process monitoring. The IAEA is also evaluating analytical laboratory instruments, such as laser-ablation inductively-coupled plasma mass spectrometry (LA-ICP-MS) for interrogating individual particles to determine uranium isotopic ratios in collected environment samples. Recent laser technology advancements will likely continue to fuel future IAEA adoption of new and novel laser-based safeguards tools. The Pacific Northwest National Laboratory (PNNL) is currently developing one such tool, called laser ablation, absorption ratio spectrometry (LAARS), for quantitative measurements of uranium material. LAARS uses three tunable diode lasers to simultaneously measure atomic 235U and 238U absorption in an ablation plume created by a fourth pulsed laser. Commercial availability of compact pulsed ablation lasers and the extreme wavelength accuracy and stability of PNNL’s tunable diode laser architecture play a pivotal role in achieving high fidelity LAARS assay measurements. The LAARS method is ultimately targeted for either on-site or laboratory-based 235U relative abundance measurements of destructive assay (DA) samples in support of uranium enrichment plant safeguards. DA samples are currently collected on-site, and then shipped to an analytical laboratory for mass spectrometric assay, because the measurement uncertainty requirements for this application are quite challenging. This paper will present the key elements of the LAARS laser system design, recent assay results on collected uranium hexafluoride (UF6) DA samples, and future operational configurations that may provide immediate on-site DA inspection results or rapid laboratory DA sample screening to prioritize further analysis by mass spectrometry.

IAEA, Safeguards, Uranium Enrichment Plants↗

Laser based 100 GeV electron acceleration scheme for muon production

High energy muons, due to their unique ability to penetrate deeply into matter, can enable radiography of structures that cannot be probed by other forms of radiation. Current terrestrial sources of muons require conventional GeV-TeV particle accelerators which are hundreds to thousands of meters in size. Laser wakefield acceleration (LWFA) can achieve acceleration gradients of two-to-three orders of magnitude greater than conventional accelerators, thus shrinking the accelerator to a number of meters. We propose a concept for a compact muon source based on the first self-consistent PIC simulations of an all optical LWFA that uses a guiding channel to achieve electron energies of 100 GeV in a distance of 6 m with a driving laser energy of 300 J in a single stage. From the resulting electron energy spectrum we estimate muon production for this source. We show that this accelerator, coupled with high average power laser driver technology, provides the basis for a high energy and high flux muon source.

laser-produced plasmas↗

A portable fiber optic sensor for the luminescent sensing of cobalt ions using carbon dots

Cobalt is critical to energy-relevant technologies, and demand for cobalt will increase significantly with growing global adoption of renewables. However, supply chain stability is threatened by economic and geopolitical factors, incentivizing domestic cobalt production from alternative resources such as coal, coal utilization byproducts (e.g., ash, acid mine drainage) and electronic waste. Rapid, inexpensive, and portable characterization techniques are needed to reduce production costs associated with cobalt prospecting and process monitoring. Here, in this research, we develop a compact, portable fiber optic luminescent probe for cobalt using phosphorus and nitrogen co-doped carbon dots as the sensing material. The carbon dot emission overlaps well with the cobalt absorption band at ~510 nm, leading to a selective decrease in emission as a function of cobalt concentration. The system responds nearly instantly to the presence of cobalt, with detection limits of 0.7 and 3.5 ppm in water and pH 1.68 buffer, respectively, providing comparable performance to a commercial spectrometer at a significantly lower cost. Moreover, the sensor is selective for cobalt in the presence of 13 of the most common metal ions encountered in coal utilization byproducts and is responsive to cobalt when spiked into an acid mine drainage leachate sample, highlighting the sensor's potential for real-world deployment in challenging matrices. In addition, integrating the carbon dots with a filter paper substrate produced ‘test strip’ sensors that exhibited a selective and sensitive visual response to cobalt using a handheld UV lamp. Taken together, the sensing system represents a significant step forward in the development of low-cost practical sensors for high-value metals in complex streams.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Low power implementation of high frequency SiPM readout for Cherenkov and scintillation detectors in TOF-PET

State-of-the-art (SoA) electronic readout for silicon photomultiplier (SiPM)-based scintillation detectors that demonstrate experimental limits in achievable coincidence time resolution (CTR) leverage low noise, high frequency signal processing to facilitate a single photon time response that is near the limit of the SiPMs architecture. This readout strategy can optimally exploit fast luminescence and prompt photon populations, and promising measurements show detector concepts employing this readout can greatly advance PET detector CTR, relative to SoA in clinical systems. However, the technique employs power hungry components which make the electronics chain impractical for channel-dense time-of-flight (TOF)-PET detectors. We have developed and tested a low noise and high frequency readout circuit which is performant at low power and consists of discrete elements with small footprints, making it feasible for integration into TOF-PET detector prototypes. A 3 × 3 mm 2 Broadcom SiPM with this readout chain exhibited sub-100 ps single photon time resolution at 10 mW of power consumption, with a relatively minor performance degradation to 120 ± 2 ps FWHM at 5 mW. CTR measurements with 3 × 3 × 20 mm 3 LYSO and fast LGSO scintillators demonstrated 127 ± 3 ps and 113 ± 2 ps FWHM at optimal power operation and 133 ± 2 ps and 121 ± 3 ps CTR at 5 mW. BGO crystals 3 × 3 × 20 mm 3 in size show 271 ± 5 ps FWHM CTR (1174 ± 14 ps full-width-at-tenth-maximum (FWTM)) at optimal power dissipation and 289 ± 8 ps (1296 ± 33 ps FWTM) at 5 mW. The compact and low power readout topology that achieves this performance thereby offers a platform to greatly advance PET system CTR and also opportunities to provide high performance TOF-PET at reduced material cost.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

Review of Ultrafast Switching Power Modules: Trends, Challenges, and Technical Solutions

Benefiting from the superior properties of wide-bandgap semiconductor materials, wide-bandgap power devices demonstrate exceptional switching performance, enabling more efficient and compact power electronics systems. However, ultrafast switching poses challenges to the reliability of the system in terms of severe oscillations and voltage overshoot, electromagnetic interference, and increased risk of partial discharge. By developing advanced power module packaging for fast-switching power devices, the above-mentioned challenges can be mitigated at the packaging level, enabling the full utilization of the fast-switching capability of wide-bandgap devices. Meanwhile, such technology also lays the groundwork for packaging next-generation power devices with even higher blocking voltage and faster switching speed. In this paper, a comprehensive review of ultrafast switching power modules has been made, including the benefits and status of ultrafast switching power modules, challenges brought by ultrafast switching, and promising technologies to address these challenges. In addition, future development trends and research gaps are also discussed in this paper. Furthermore, this review can serve as a reference for future wide-bandgap power module packaging design.

24 POWER TRANSMISSION AND DISTRIBUTION↗

w22_laser-radiography: Laser-Based MeV Radiography [Slides]

X-ray sources based on high-power short pulse lasers have unique advantages over conventional sources, like small spot size, flexible configuration, and tailorable spectra. Development of these sources will allow LANL to fulfill an urgent need to deploy flexible, compact, x-ray sources for static and dynamic radiography at our firing sites and facilities such as pRad and U1a. Our IC allocation supports the development of a predictive modeling capability of these laser-based sources.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

A Quiet Helicopter for Air Taxi Operations

NASA is exploring rotorcraft designs for VTOL air taxi operations, also known as urban air mobility (UAM) or on-demand mobility (ODM) applications. Several concept vehicles have been developed, intended to focus and guide NASA research activities in support of aircraft development for this emerging market. This paper examines a single main-rotor helicopter designed specifically for low-noise air taxi operations. Based on demonstrated technology, the aircraft uses a turboshaft engine with a sound-absorbing installation, and the NOTAR anti-torque system to eliminate tail-rotor noise, consequently the noise and annoyance of the aircraft are dominated by the main rotor. Several design parameters are explored to reduce the noise, including rotor tip speed, blade geometry, and higher-harmonic control. Commensurate with the level of design detail, the noise is calculated for compact loading and thickness sources on the rotating blades. The metric is the reduction of the noise for the helicopter certification conditions (takeoff, flyover, and approach), relative a baseline aircraft with typical (high) tip speed, conventional blade planform, and no higher-harmonic control.

Johnson, Wayne↗

Subsonic-Transport Core/Combustor Noise

The presentation is an overview of the propulsion-noise contributions from sources associated with the combustor for subsonic-transport aircraft. Sections of the talk cover: the impact of future compact high-efficiency core design trends on airport-community noise, the physical source mechanisms responsible for direct and indirect combustor noise, and combustor-noise prediction and measurement. The noise issues discussed are important to future gas-turbine propulsors, to envisioned hybrid-electric aircraft propulsion systems, and represent key challenges in the strategy to develop novel propulsion systems for ultra-efficient transport aircraft. The Advanced Air Transport Technology Project supports this effort.

Aeroacoustics, Combustor Noise, Turbomachinery Noi↗

A 40 Gbps Optical Transceiver for Particle Physics Experiments

We present the design and the test results of a quad-channel optical transceiver module (QTRx) possibly for future particle physics experiments. The transmitters of QTRx, each at 10 Gbps, are based on a Quad-channel VCSEL Diode array Driver (QLDD) and 1 x 4 VCSEL array. The receivers of QTRx, with data rates of 2.56 Gbps or 10 Gbps per channel, are based on a Quad-channel Trans-Impedance and limiting Amplifier (QTIA) and 1 x 4 photodiode array of GaAs or InGaAs. QTRx is 20 mm x 10 mm x 5 mm and couples to an MT fiber connector. Test results indicate that QTRx achieves the design goals with a power consumption of 124 mW per transmitter channel at 10 Gbps and 120 mW at 2.56 Gbps for the receiver channel with an on-chip charge pump. The sensitivities of QTIA are -17 dBm at 2.56 Gbps and -8 dBm at 10 Gbps, respectively. Further improvements with a gold-finger interface and a more compact optical lens are being designed.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

Advanced Waste Management Concepts for Uranium and Plutonium Multi-Recycling - 18533

The multiple recycling of plutonium and uranium will play a major role in gradually achieving a fully closed nuclear fuel cycle in the future, once the first Generation IV fast reactors (FR) are deployed in the NPP fleet. To reach this objective, optimizations of current processes and technologies and, in some cases, the development of innovative concepts are required to meet the scientific, technical and economic challenges imposed by the treatment of spent fuels with an increasingly higher Pu content. Based on the significant past experience acquired by France in LWR and FR MOX fuel treatment, the CEA is running R and D studies to develop new efficient processes for Pu recycling and for FR MOX fuel fabrication. More compact and economically competitive processes, ensuring the safety/security of the facilities (particularly as regards criticality and proliferation resistance) have to be developed taking into account that the amounts of plutonium involved will be one order of magnitude higher than in UOX fuels. New concepts of head-end treatment, dissolution, and separation have been proposed. Consequently, effluent and waste management must be adapted to these processes and to the characteristics of fast reactor MOX fuels. New waste treatment processes are suggested: 1) Cladding waste and undissolved metallic particles could be treated simultaneously in a melting process. The molten metal could be decontaminated by a specific slag and the oxides recovered, in particular PuO{sub 2}, would be recycled at the frond-end of the process, 2) Fission Products and Actinides (FPA) containment glass will also be optimized to accommodate significant amounts of iron, nickel and chromium coming from hull corrosion, and / or decontamination slag coming from the metal melting process. 3) New peraluminous-type glass formulations are under development to accept increased amounts of FPA, as well as iron, nickel, and chromium. The first trials to evaluate the melting process have indicated that metallic compounds from the dissolution residues could be easily incorporated into a molten metal at levels of 1, 2 and 3 w%. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Development of an advanced spacecraft tandem mass spectrometer

The purpose of this research was to apply current advanced technology in electronics and materials to the development of a miniaturized Tandem Mass Spectrometer that would have the potential for future development into a package suitable for spacecraft use. The mass spectrometer to be used as a basis for the tandem instrument would be a magnetic sector instrument, of Nier-Johnson configuration, as used on the Viking Mars Lander mission. This instrument configuration would then be matched with a suitable second stage MS to provide the benefits of tandem MS operation for rapid identification of unknown organic compounds. This tandem instrument is configured with a newly designed GC system to aid in separation of complex mixtures prior to MS analysis. A number of important results were achieved in the course of this project. Among them were the development of a miniaturized GC subsystem, with a unique desorber-injector, fully temperature feedback controlled oven with powered cooling for rapid reset to ambient conditions, a unique combination inlet system to the MS that provides for both membrane sampling and direct capillary column sample transfer, a compact and ruggedized alignment configuration for the MS, an improved ion source design for increased sensitivity, and a simple, rugged tandem MS configuration that is particularly adaptable to spacecraft use because of its low power and low vacuum pumping requirements. The potential applications of this research include use in manned spacecraft like the space station as a real-time detection and warning device for the presence of potentially harmful trace contaminants of the spacecraft atmosphere, use as an analytical device for evaluating samples collected on the Moon or a planetary surface, or even use in connection with monitoring potentially hazardous conditions that may exist in terrestrial locations such as launch pads, environmental test chambers or other sensitive areas. Commercial development of the technology could lead to a new family of environmental test instruments that would be small and portable, yet would give quick analyses of complex samples.

Drew, Russell C.↗

Supportability Technologies for Future Exploration Missions

Future long-duration human exploration missions will be challenged by resupply limitations and mass and volume constraints. Consequently, it will be essential that the logistics footprint required to support these missions be minimized and that capabilities be provided to make them highly autonomous from a logistics perspective. Strategies to achieve these objectives include broad implementation of commonality and standardization at all hardware levels and across all systems, repair of failed hardware at the lowest possible hardware level, and manufacture of structural and mechanical replacement components as needed. Repair at the lowest hardware levels will require the availability of compact, portable systems for diagnosis of failures in electronic systems and verification of system functionality following repair. Rework systems will be required that enable the removal and replacement of microelectronic components with minimal human intervention to minimize skill requirements and training demand for crews. Materials used in the assembly of electronic systems (e.g. solders, fluxes, conformal coatings) must be compatible with the available repair methods and the spacecraft environment. Manufacturing of replacement parts for structural and mechanical applications will require additive manufacturing systems that can generate near-net-shape parts from the range of engineering alloys employed in the spacecraft structure and in the parts utilized in other surface systems. These additive manufacturing processes will need to be supported by real-time non-destructive evaluation during layer-additive processing for on-the-fly quality control. This will provide capabilities for quality control and may serve as an input for closed-loop process control. Additionally, non-destructive methods should be available for material property determination. These nondestructive evaluation processes should be incorporated with the additive manufacturing process - providing an in-process capability to ensure that material deposited during layer-additive processing meets required material property criteria.

Watson, Kevin↗

Circularly Polarized Thermal Radiation From Nonequilibrium Coupled Antennas

Circularly polarized light can be obtained by using either polarization conversion or structural chirality. Here we reveal a fundamentally unrelated mechanism of generating circularly polarized light using coupled nonequilibrium sources. We show that thermal emission from a compact dimer of subwavelength, anisotropic antennas can be highly circularly polarized when the antennas are at unequal temperatures. Furthermore, the handedness of emitted light is flipped upon interchanging the temperatures of the antennas, thereby enabling reconfigurability of the polarization state lacked by most circularly polarized light sources. Furthermore, we describe the fundamental origin of this mechanism using rigorous fluctuational electrodynamic analysis and further provide practical examples for its experimental implementation. Apart from the technology applications in reconfigurable devices, communication, and sensing, this work motivates new inquiries of angular-momentum-related thermal-radiation phenomena using thermal nonequilibrium, without applying magnetic field.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗

Formation of Sub-Millimeter-Size Powerful X-Ray Sources in Low-Impedance Rod-Pinch Diodes

In the paper, experiments on the formation of a low-impedance diode and a focused electron beam as a result of detachment of radial wires, accelerated by the current of a high-current generator, from the rod anode have been described. In the experiments, along with studies of conditions for compact focusing of the electron beam and effective generation of hard x-rays, the shape of the tip of the anode rod is determined at which the x-ray source is point-sized when viewed in the radial direction.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

Compact readout of large CLYC scintillators with silicon photomultipler arrays

Compact readout of a large (5 x 5 x 5 cm 3) CLYC scintillator was demonstrated with a 8 x 8 array of 6mm silicon photomultipliers (SiPMs, specifically, a SensL ArrayJ-60035-64P) and an optimized amplification and summing circuit. Read out by the SiPM array, the crystal yielded an energy resolution of 5.5% at 662 keV and a figure of merit of 3.5, equivalent to the performance achieved with a 3-inch Hamamatsu R6233-100 PMT. To reduce channel count and avoid individual amplification of each SiPM in the array, the standard outputs of 16 SiPMs were passively summed then amplified. A current feedback amplifier was used for each channel to provide the required fast response time. The four amplified channels were then passively summed resulting in a single signal channel. A custom laboratory setup, based on the PSD8C ASIC, was used to capture the output and provide time-gated integration for PSD computation. We conclude the compact volume, low bias voltage, and reduced mass of the SiPM array readout are desirable for space and national security applications.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

A gaseous RICH detector for SiD or ILD

This paper describes a preliminary study of a gaseous Ring Imaging Cherenkov (RICH) system capable of discriminating between kaons and pions at high momenta — up to 50 GeV/c — and thus enhancing particle identification at future colliders. The system possesses a compact design, facilitating easy integration into existing detector concepts. Here, a study of the key contributions to the Cherenkov angle resolution is also presented.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

Optimal Pulse Processing, Pile-Up Decomposition, and Applications of Silicon Drift Detectors at LCLS

Silicon drift detectors (SDDs) revolutionized spectroscopy in fields as diverse as geology and dentistry. For a subset of experiments at ultrafast, X-ray free-electron lasers (FELs), SDDs can make substantial contributions. Often the unknown spectrum is interesting, carrying science data, or the background measurement is useful to identify unexpected signals. Many measurements involve only several discrete photon energies known a priori, allowing single-event decomposition of pile-up and spectroscopic photon counting. We designed a pulse function and demonstrated that the signal amplitude (i.e., proportional to the detected energy and obtained from fitting with the pulse function), rise time, and pulse height are interrelated, and at short peaking times, the pulse height and pulse area are not optimal estimators for detected energy; instead, the signal amplitude and rise time are obtained for each pulse by fitting, thus removing the need for pulse shaping. By avoiding pulse shaping, rise times of tens of nanoseconds resulted in reduced pulse pile-up and allowed decomposition of remaining pulse pile-up at photon separation times down to hundreds of nanoseconds while yielding time-of-arrival information with the precision of 10 ns. Waveform fitting yields simultaneously high energy resolution and high counting rates (two orders of magnitude higher than current digital pulse processors). At pulsed sources or high photon rates, photon pile-up still occurs. We showed that pile-up spectrum fitting is relatively simple and preferable to pile-up spectrum deconvolution. We then developed a photon pile-up statistical model for constant intensity sources, extended it to variable intensity sources (typical for FELs), and used it to fit a complex pileup spectrum. We subsequently developed a Bayesian pile-up decomposition method that allows decomposing pile-up of single events with up to six photons from six monochromatic lines with 99% accuracy. The usefulness of SDDs will continue into the X-ray FEL era of science. Their successors, the ePixS hybrid pixel detectors, already offer hundreds of pixels, each with a similar performance to an SDD, in a compact, robust and affordable package.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

Optofluidic memory and self-induced nonlinear optical phase change for reservoir computing in silicon photonics

Nanophotonics allows to employ light-matter interaction to induce nonlinear optical effects and realize non-conventional memory and computation capabilities, however to date, light-liquid interaction was not considered as a potential mechanism to achieve computation on a nanoscale. Here, we experimentally demonstrate self-induced phase change effect which relies on the coupling between geometric changes of thin liquid film to optical properties of photonic waveguide modes, and then employ it for neuromorphic computing. In our optofluidic silicon photonics system we utilize thermocapillary-based deformation of thin liquid film capable to induce nonlinear effect which is more than one order of magnitude higher compared to the more traditional heat-based thermo-optical effect, and allowing operation as a nonlinear actuator and memory element, both residing at the same compact spatial region. The resulting dynamics allows to implement Reservoir Computing at spatial region which is approximately five orders of magnitude smaller compared to state-of-the-art experimental liquid-based systems.

42 ENGINEERING↗