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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 127 records · Page 7
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Design study of a combined interferometer and polarimeter for a high-field, compact tokamak

This article is the first design study of a combined interferometer and polarimeter on a compact, high-field, high-density, net-energy tokamak. Recent advances in superconducting technology have made possible designs for compact, high magnetic field fusion power plants, such as ARC [Sorbom et al., Fusion Eng. Des. 100, 378 (2015)], and experiments, such as SPARC [Greenwald et al., PSFC Report No. RR-18-2 (2018)]. These new designs create both challenges and opportunities for plasma diagnostics. The diagnostic proposed in this work, called InterPol, takes advantage of unique opportunities provided by high magnetic field and density to measure both line-averaged density and poloidal magnetic field with a single set of CO 2 and quantum cascade lasers. These measurements will be used for fast density feedback control, constraint of density and safety factor profiles, and density fluctuation measurements. Synthetic diagnostic testing using a model machine geometry, called MQ1 (Mission Q ≥ 1), and profiles simulated with Tokamak Simulation Code indicate that InterPol will be able to measure steady state density and poloidal magnetic field, as well as fluctuations caused by toroidal Alfven eigenmodes and other phenomena on a high-field compact tokamak.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
NASA NTRS1994

Lidar performance analysis

Section 1 details the theory used to build the lidar model, provides results of using the model to evaluate AEOLUS design instrument designs, and provides snapshots of the visual appearance of the coded model. Appendix A contains a Fortran program to calculate various forms of the refractive index structure function. This program was used to determine the refractive index structure function used in the main lidar simulation code. Appendix B contains a memo on the optimization of the lidar telescope geometry for a line-scan geometry. Appendix C contains the code for the main lidar simulation and brief instruction on running the code. Appendix D contains a Fortran code to calculate the maximum permissible exposure for the eye from the ANSI Z136.1-1992 eye safety standards. Appendix E contains a paper on the eye safety analysis of a space-based coherent lidar presented at the 7th Coherent Laser Radar Applications and Technology Conference, Paris, France, 19-23 July 1993.

Spiers, Gary D.↗
NASA NTRS2000

A Little Sensor That Packs a Wallop

A gas sensor originally built for NASA to measure the composition of the atmosphere of Earth and Mars has been commercialized by SpectraSensors. The commercial tunable diode laser (TDL) gas sensor can be used for oil and gas pipeline monitoring, aircraft safety, environmental monitoring and medicine. The TDL technology is good at detecting low levels of gases from parts-per-million to parts-per-billion.

Source record↗
DOE OSTI2026

Innovative laser-based methods for monitoring fuel retention in ITER

This paper addresses the challenge of tritium inventory management in ITER and future fusion reactors, highlighting the importance of accurate tritium measurement and its spatial distribution within the vacuum vessel. Given ITER’s operational constraints, especially the limit on tritium retention, precise measurement is essential for both safety and regulatory compliance. To tackle these questions, the paper presents the T-monitor diagnostic system developed by Forschungszentrum Jülich, which uses Laser-Induced Desorption (LID) in combination with Diagnostic Residual Gas Analysis (DRGA) to measure hydrogen isotope concentrations on the surface of divertor tiles. The system integrates a high-power laser, advanced optical components, and a Fast Scanning Mirror Unit (FSMU) for accurate laser spot positioning with rapid response. Designed to measure in situ tritium retention, the diagnostic provides high-resolution spatial mapping, vital for evaluating detritiation strategies. The laser heating process increases the divertor surface temperature to 1600 K within the laser spot, promoting hydrogen isotope desorption. Accurate measurements require the precise control of laser parameters, including pulse duration and spot size, with a target relative accuracy of 20%. The optical design includes both in-vessel and ex-vessel components, such as durable high-reflectivity mirrors made of gold and copper, selected not only for their infrared performance but also for their transmission of visible wavelengths for observation purposes. To protect optical components from contamination, a pneumatic shutter is used.

Hydrogen isotopes↗
NASA NTRS2011

Optical air data systems and methods

Systems and methods for sensing air includes at least one, and in some embodiments three, transceivers for projecting the laser energy as laser radiation to the air. The transceivers are scanned or aligned along several different axes. Each transceiver receives laser energy as it is backscattered from the air. A computer processes signals from the transceivers to distinguish molecular scattered laser radiation from aerosol scattered laser radiation and determines air temperatures, wind speeds, and wind directions based on the scattered laser radiation. Applications of the system to wind power site evaluation, wind turbine control, traffic safety, general meteorological monitoring and airport safety are presented.

Caldwell, Loren M.↗
NASA NTRS2014

Spinoff 2013

Topics covered include: Innovative Software Tools Measure Behavioral Alertness; Miniaturized, Portable Sensors Monitor Metabolic Health; Patient Simulators Train Emergency Caregivers; Solar Refrigerators Store Life-Saving Vaccines; Monitors Enable Medication Management in Patients' Homes; Handheld Diagnostic Device Delivers Quick Medical Readings; Experiments Result in Safer, Spin-Resistant Aircraft; Interfaces Visualize Data for Airline Safety, Efficiency; Data Mining Tools Make Flights Safer, More Efficient; NASA Standards Inform Comfortable Car Seats; Heat Shield Paves the Way for Commercial Space; Air Systems Provide Life Support to Miners; Coatings Preserve Metal, Stone, Tile, and Concrete; Robots Spur Software That Lends a Hand; Cloud-Based Data Sharing Connects Emergency Managers; Catalytic Converters Maintain Air Quality in Mines; NASA-Enhanced Water Bottles Filter Water on the Go; Brainwave Monitoring Software Improves Distracted Minds; Thermal Materials Protect Priceless, Personal Keepsakes; Home Air Purifiers Eradicate Harmful Pathogens; Thermal Materials Drive Professional Apparel Line; Radiant Barriers Save Energy in Buildings; Open Source Initiative Powers Real-Time Data Streams; Shuttle Engine Designs Revolutionize Solar Power; Procedure-Authoring Tool Improves Safety on Oil Rigs; Satellite Data Aid Monitoring of Nation's Forests; Mars Technologies Spawn Durable Wind Turbines; Programs Visualize Earth and Space for Interactive Education; Processor Units Reduce Satellite Construction Costs; Software Accelerates Computing Time for Complex Math; Simulation Tools Prevent Signal Interference on Spacecraft; Software Simplifies the Sharing of Numerical Models; Virtual Machine Language Controls Remote Devices; Micro-Accelerometers Monitor Equipment Health; Reactors Save Energy, Costs for Hydrogen Production; Cameras Monitor Spacecraft Integrity to Prevent Failures; Testing Devices Garner Data on Insulation Performance; Smart Sensors Gather Information for Machine Diagnostics; Oxygen Sensors Monitor Bioreactors and Ensure Health and Safety; Vision Algorithms Catch Defects in Screen Displays; and Deformable Mirrors Capture Exoplanet Data, Reflect Lasers.

Source record↗
NASA NTRS1993

Laser diode ignition activities at Sandia National Laboratories

The topics are presented in viewgraph form and include the following: ignition subsystems, enhanced safety, optical ordnance power densities, optical ignition factors, low energy optical ordnance program, absorptance of 2-(5-cyanotetrazolato) pentaaminecobalt(III) perchlorate (CP) near 800 nm, power dependence of doped CP, system operational electrical requirements, dopant concentration effects for different CP particle sizes, ZR/KCLO4 optical ignition thresholds, and electrostatic discharge testing.

Merson, John A.↗
NASA NTRS1993

Imaging Hydrogen Leaks With Raman Scattering

Proposed spectral imaging system used to detect leaking hydrogen from distance of 100 ft or more. Video cameras form images of leaking hydrogen by use of Raman scattering of laser beam from hydrogen. By indicating potentially explosive concentrations of hydrogen in air, system contributes to safety at facilities producing and handling hydrogen, such as fueling stations for hydrogen-burning automobiles of near future.

Mcdermid, Iain S.↗
DOE OSTI2026

Air attenuation of high power XFEL beams

The Linac Coherent Light Source-II, a high-repetition-rate x-ray free electron laser, produces high average power as well as high peak power. Air is a key radiation safety element, helping to contain the FEL beams from reaching accessible areas. At high average power, air absorption can produce a high temperature and low-density channel along the x-ray beam path. In this case, the x-ray attenuation no longer follows the Beer-Lambert equation, e-μx . Air attenuation measurements were performed with x-rays focused into a gas cell at the LCLS Time-resolved AMO instrument. The air transmission was observed to significantly increase with x-ray power. Simulations were also performed, which include the thermal processes related to the high average power. In comparison to the measurements, the calculated air transmission is higher, confirming that the simulations are conservative and suitable for radiation safety analyses.

42 ENGINEERING↗
DOE OSTI2025

Laser ablation of high-loading Li-ion battery electrodes improves accessible capacity and cycle life for Behind-the-Meter Storage

Adoption of Behind-the-Meter Storage (BTMS) requires design of batteries that enable high safety, long cycle life, and low cost at the system level. Pairing Li 4 Ti 5 O 12 (LTO) with LiMn 2 O 4 (LMO) achieves targets related to safety and cycle life, but these materials' low energy densities contribute to higher cost at the system scale. Increasing electrode loading is a simple approach to improve energy density, but comes with a trade-off in electrode utilization due to long, tortuous Li + diffusion pathways. Here, laser ablation is used to microstructure (pattern) high-loading electrodes to enhance electrode performance through improved Li + diffusion pathways. Four cell types, comprising combinations of standard or patterned anode and cathode, were prepared to evaluate the effects of laser ablation at each electrode. A rate test shows that patterning electrodes enhances active material utilization at ≳1C rates. Patterning the cathode yields the most benefit, as cells with a patterned cathode demonstrate a ~20% higher accessible capacity than those without at 1.4C. Additionally, 1C capacity retention of cells with patterned cathode (91% through 3000 cycles) is significantly improved over cells with only the anode patterned (64%) and non-patterned electrodes (50%). Characterization of post-mortem cells before and after refreshing their electrolyte suggests that 1C capacity retention is improved by mitigation of electrode "dry-out". We hypothesize that the microstructure acts as a reservoir of additional electrolyte, or a path for gas to escape, so that active material remains wetted throughout long-term cycling, and/or the microstructure may reduce localized, gas-forming overpotentials in the high-loading electrode.

25 ENERGY STORAGE↗
DOE OSTI2023

Nanosecond Laser Drying in Wafer Foundries for Significant Energy Efficiency Improvement

Surface drying is a critical process in microelectronics wafer fabrication. In order to reduce and eliminate watermarks, many surface drying processes have been studied and used. Most of the wafer foundries currently use drying processes based on Isopropyl Alcohol (IPA), which causes serious safety (fire), health, environmental, and energy efficiency issues. The long-term goal of this project is to develop a fast, effective, chemical-free, and extremely energy efficient wafer drying technology that employs nanosecond laser-induced sub-surface evaporation and explosion. The objectives of this project are to 1) experimentally develop and verify the laser surface drying method, explore and identify how and to what extent various physical parameters influence the drying efficiency and effectiveness; and 2) understand and optimize the underlying thermodynamics in the proposed laser surface drying, including micro/nanoscale sub-surface superheating, evaporation, explosion, and photo/thermochemical bond breaking via atomistic modeling and experimental characterization. Toward these objectives, five tasks have been accomplished successfully, including 1) develop in-lab laser surface drying setup and study the effect of varied laser parameters, 2) use multiscale hybrid-modeling to study and understand the physics of water behavior during drying toward process optimization, 3) investigate the effect of drying conditions on the drying effectiveness, 4) develop a large-scale laser drying scanning system with automatic scanning, and 5) conduct large-scale simulation to study the effect of dopant level and develop strategies for system development toward industry deployment.

42 ENGINEERING↗
NASA NTRS1978

NASA technical advances in aircraft occupant safety

A NASA program to improve aircraft safety is discussed in terms of three areas of concentration: unexpected turbulence encounters, fire, and crash impact. To provide warning of clear air turbulence (CAT) so that the pilot can take evasive action, a laser Doppler system is described, which functions by measuring backscatter frequency radiation occurring in aerosols ahead of the aircraft. The system was found able to detect CAT, but at shorter than optimal ranges (10 km as opposed to 32 km). Fire safety has focused on both the early detection of fires through improved sensing methods, and on the development of fire-retardant materials, i.e., intumescent char-forming protective coatings. Crashworthiness is discussed in terms of the development of a survivable crash envelope and improved seat and restraint systems. To evaluate an aircraft for crashworthiness, finite-element computer programs are currently being developed which analyze both aircraft structural configurations and the intrinsic strength of aircraft materials.

Enders, J. H.↗
NASA NTRS1998

Nineteenth International Laser Radar Conference

This publication contains extended abstracts of papers presented at the Nineteenth International Laser Radar Conference, held at Annapolis, Maryland, July 6-10, 1998; 260 papers were presented in both oral and poster sessions. The topics of the conference sessions were Aerosol Clouds, Multiple Scattering; Tropospheric Profiling; Stratospheric/Mesospheric Profiling; Wind Profiling; New Lidar Technology and Techniques; Lidar Applications, including Altimetry and Marine; Space and Future Lidar; and Lidar Commercialization/Eye Safety. This conference reflects the breadth of research activities being conducted in the lidar field. These abstracts address subjects from lidar-based atmospheric investigations, development of new lasers and lidar system technology, and current and future space-based lidar systems.

Upendra N. Singh↗
NASA NTRS1998

Nineteenth International Laser Radar Conference

This publication contains extended abstracts of papers presented at the Nineteenth International Laser Radar Conference, held at Annapolis, Maryland, July 6-10, 1998; 260 papers were presented in both oral and poster sessions. The topics of the conference sessions were Aerosol Clouds, Multiple Scattering; Tropospheric Profiling, Stratospheric/Mesospheric Profiling; Wind Profiling; New Lidar Technology and Techniques; Lidar Applications, Including Altimetry and Marine; Space and Future Lidar; and Lidar Commercialization/Eye Safety. This conference reflects the breadth of research activities being conducted in the lidar field. These abstracts address subjects from lidar-based atmospheric investigations, development of new lasers and lidar system technology, and current and future space-based lidar systems.

Upendra N. Singh↗
NASA NTRS1988

Ultraviolet Lidar Would Measure Wind Velocity

Incoherent Doppler-shifted scattering from aerosols reveals important weather data. Remote-sensing system in early stage of development makes global measurements of wind velocities along probing beam of ultraviolet light. In aviation system promotes safety through detection of wind shears and clear-air turbulence. System includes range-gated ultraviolet-excimer laser operating at 308 or 353 nm.

Mcdermid, Iain Stuart↗
NASA NTRS2006

Potential Alternatives Report for Validation of Alternative Low-Emission Surface PreparationlDepainting Technologies for Structural Steel

For this project, particulates and solvents used during the depainting process of steel structures were the identified hazardous material (HazMat) targeted for elimination or reduction. This Potential Alternatives Report (PAR) provides technical analyses of identified alternatives to the current coating removal processes, criteria used to select alternatives for further analysis, and a list of those alternatives recommended for testing. The initial coating removal alternatives list was compiled using literature searches and center participant recommendations. The involved project participants initially considered fifteen (15) alternatives. In late 2004, stakeholders down-selected the list and identified specific processes as potential alternatives to the current depainting methods. The selected alternatives were: 1. Plastic Blast Media 2. Hard Abrasive Media 3. Sponge Blast Media 4. Mechanical Removal with Vacuum Attachment 5. Liquid Nitrogen 6. Laser Coating Removal Available information about these processes was used to analyze the technical merits and the potential environmental, safety, and occupational health (ESOH) impacts of these methods. A preliminary cost benefit analysis will be performed to determine if implementation of alternative technologies is economically justified. NASA AP2

Lewis, Pattie↗
NASA NTRS2013

Conductive Carbon Nanotube Inks for Use with Desktop Inkjet Printing Technology

Inkjet printing is a common commercial process. In addition to the familiar use in printing documents from computers, it is also used in some industrial applications. For example, wire manufacturers are required by law to print the wire type, gauge, and safety information on the exterior of each foot of manufactured wire, and this is typically done with inkjet or laser printers. The goal of this work was the creation of conductive inks that can be applied to a wire or flexible substrates via inkjet printing methods. The use of inkjet printing technology to print conductive inks has been in testing for several years. While researchers have been able to get the printing system to mechanically work, the application of conductive inks on substrates has not consistently produced adequate low resistances in the kilohm range. Conductive materials can be applied using a printer in single or multiple passes onto a substrate including textiles, polymer films, and paper. The conductive materials are composed of electrical conductors such as carbon nanotubes (including functionalized carbon nanotubes and metal-coated carbon nanotubes); graphene, a polycyclic aromatic hydrocarbon (e.g., pentacene and bisperipentacene); metal nanoparticles; inherently conductive polymers (ICP); and combinations thereof. Once the conductive materials are applied, the materials are dried and sintered to form adherent conductive materials on the substrate. For certain formulations, increased conductivity can be achieved by printing on substrates supported by low levels of magnetic field alignment. The adherent conductive materials can be used in applications such as damage detection, dust particle removal, smart coating systems, and flexible electronic circuitry. By applying alternating layers of different electrical conductors to form a layered composite material, a single homogeneous layer can be produced with improved electrical properties. It is believed that patterning alternate layers of different conductors may improve electrical pathways through alignment of the conductors and band gap optimization. One feature of this innovation is that flexible conductive traces could be accomplished with a conductive ink having a surface resistivity of less than 10 ohms/square. Another result was that a composite material comprising a mixture of carbon nanotubes and metallic nanoparticles could be applied by inkjet printing to flexible substrates, and the resulting applied material was one to two orders of magnitude more conductive than a material made by printing inks containing carbon nanotubes alone.

Roberson, Luke↗
DOE OSTI2020

Microwave ignition of energetic material housed within a gun

The systems and methods for microwave ignition of energetic material housed within a gun (e.g., primers and/or propellants) allow for the use of insensitive energetic materials and/or insensitive gas-generating materials in place of sensitive energetic materials relied upon by mechanical ignition systems. In some embodiments, the use of insensitive energetic materials and/or insensitive gas-generating materials increase the safety and reliability of guns that would otherwise need to depend on sensitive energetic material required by mechanical or laser ignition mechanisms. Additionally, in some embodiments, the systems and methods provide greater versatility with respect to the variety of energetic materials that may be employed within guns.

42 ENGINEERING↗