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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 1,765 records · Page 98
All sourcesNASA NTRSDOE OSTI
NASA NTRSDate not supplied

Implementation of a Compact Self-Aligned Focusing Schlieren System for Measurements with the SBLT-II Flight Test Article

Previous flight testing of a supersonic natural laminar flow airfoil on the NASA F-15Baircraft showed evidence of multiple impinging shocks (shock train) of unknown origin, which generated sufficient crossflow on the airfoil to affect the primary measurement goal of transition location. A compact self-aligned focusing schlieren (SAFS) system is being developed to visualize this shock train on the forward surface of the Supersonic Boundary Layer Transition - PhaseII (SBLT-II) flight test article. Details of the design of the SAFS flight system, the constraints imposed by the imaging pod that will be mounted to the F-15B aircraft, preliminary laboratory results obtained with the system, and challenges associated with integrating the imaging system into the aircraft are presented. The resulting schlieren images obtained from this flight test will allow for a three-dimensional reconstruction of the unknown shock structure, validating the use of SAFS for flight testing.

Joshua M. Weisberger↗
NASA NTRSDate not supplied

Self-Aligned Focusing Schlieren and OH Planar Laser-Induced Fluorescence Flow Visualization in a Dual-Mode Scramjet

Ahigh-speed self-aligned focusing schlieren (SAFS) system was used to visualize density gradients in and around the cavity flameholder of the combustor section of the University of Virginia Supersonic Combustion Facility (UVASCF). Images with this system were acquired at a framing rate of 110 kHz with no fuel injection, with fuel injection but no flame, and for fuel injection with combustion corresponding to a global equivalence ratio of 𝜙 = 0.18. Images with an air throttle in operation to modify the shock train location with fuel injection and with flame were also acquired. Simultaneous OH planar laser-induced fluorescence (PLIF) images were also acquired at a framing rate of 20 Hz. Results obtained with both visualization techniques are compared to one another to highlight how SAFS can complement more advanced flow visualization techniques and resolve dynamic behavior that may not otherwise be captured. Both proper orthogonal decomposition (POD) and dynamic mode decomposition (DMD) analysis techniques are applied to the SAFS image sequences to identify coherent periodic structures for the runs with fuel injection and combustion.

Brett F Bathel↗
NASA NTRSDate not supplied

Aligned Boron Nitride Nanotube Reinforced Polyethylene Nanocomposite for Space Radiation Shielding

With NASA’s Artemis program aiming to establish a human presence on the Moon and eventually on Mars, protecting astronauts from radiation is necessary. Flight-heritage materials, like those with high hydrogen content, such as polyethylene (PE), have proven to be effective radiation shields. This is due to hydrogen’s high charge-to-mass ratio, low secondary radiation production, efficient energy absorption, and high cross-section, which increases the probability of particle interactions to slow or stop ionized particles. Boron nitride nanotubes (BNNTs) and other boron-rich materials offer more effective thermal neutron radiation-stopping capabilities due to their high cross-section and neutron absorption properties. BNNTs also enhance the mechanical properties of radiation shielding material due to their high strength-to-weight ratios. However, integrating high volumes of nanotubes in a matrix without defects presents significant manufacturing challenges. To address this, a bulk nanocomposite laminate fabricating technique, involving synthesizing millimeter-long vertically aligned BNNTs, densifying the nanotubes to high-volume fractions, and infusing the nanotubes with PE while applying heat and pressure was utilized to fabricate the BNNT-PE nanocomposite that was tested for its radiation shielding properties at NASA Langley Research Center’s neutron radiation exposure lab. Results from these experiments will be discussed in the presentation.

Palak B Patel↗
DOE OSTI2012

Vertically aligned carbon nanofiber as nano-neuron interface for monitoring neural function

Neural chips, which are capable of simultaneous, multi-site neural recording and stimulation, have been used to detect and modulate neural activity for almost 30 years. As a neural interface, neural chips provide dynamic functional information for neural decoding and neural control. By improving sensitivity and spatial resolution, nano-scale electrodes may revolutionize neural detection and modulation at cellular and molecular levels as nano-neuron interfaces. We developed a carbon-nanofiber neural chip with lithographically defined arrays of vertically aligned carbon nanofiber electrodes and demonstrated its capability of both stimulating and monitoring electrophysiological signals from brain tissues in vitro and monitoring dynamic information of neuroplasticity. This novel nano-neuron interface can potentially serve as a precise, informative, biocompatible, and dual-mode neural interface for monitoring of both neuroelectrical and neurochemical activity at the single cell level and even inside the cell.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2013

Synthesis of VACNFs on Aluminum Foil and Their Transfer to PDMS while Maintaining Alignment and Impalefection Functionality

Vertically aligned carbon nanofibers (VACNFs) are synthesized on 3003 aluminum substrates by direct current plasma enhanced chemical vapor deposition. Chemically synthesized nickel nanoparticles were used as the catalyst for growth. The silicon containing coating (SiNx) typically produced when VACNFs are grown on silicon was produced by adding silicon microparticles prior to growth. The fiber array was transferred to PDMS by spin casting a layer on the grown substrates, curing the PDMS, and etching away the aluminum in KOH. Energy dispersive x-ray spectroscopy, scanning electron microscopy, and fluorescence microscopy data are provided. The free standing array in PDMS was then loaded with pVENUS-C1 plasmid and human brain microcapillary endothelial cells (HCMECHBMEC)/d3 cells were successfully impalefected with the plasmid.

Railsback, Justin↗
DOE OSTI2012

Portable weighing system with alignment features

A system for weighing a load is disclosed. The weighing system includes a pad having at least one transducer for weighing a load disposed on the pad. In some embodiments the pad has a plurality of foot members and the weighing system may include a plate that disposed underneath the pad for receiving the plurality of foot member and for aligning the foot members when the weighing system is installed. The weighing system may include a spacer disposed adjacent the pad and in some embodiments, a spacer anchor operatively secures the spacer to a support surface, such as a plate, a railway bed, or a roadway. In some embodiments the spacer anchor operatively secures both the spacer and the pad to a roadway.

42 ENGINEERING↗
DOE OSTI2013

Structure based alignment and clustering of proteins (STRALCP)

Disclosed are computational methods of clustering a set of protein structures based on local and pair-wise global similarity values. Pair-wise local and global similarity values are generated based on pair-wise structural alignments for each protein in the set of protein structures. Initially, the protein structures are clustered based on pair-wise local similarity values. The protein structures are then clustered based on pair-wise global similarity values. For each given cluster both a representative structure and spans of conserved residues are identified. The representative protein structure is used to assign newly-solved protein structures to a group. The spans are used to characterize conservation and assign a "structural footprint" to the cluster.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2013

Towards identifying the mechanisms underlying field-aligned edge-loss of HHFW power on NSTX

Fast-wave heating will be a major heating scheme on ITER, as it can heat ions directly and is relatively unaffected by the large machine size unlike neutral beams. However, fast-wave interactions with the plasma edge can lead to deleterious effects such as, in the case of the high-harmonic fast-wave (HHFW) system on NSTX, large losses of fast-wave power in the scrape off layer (SOL) under certain conditions. In such scenarios, a large fraction of the lost HHFW power is deposited on the upper and lower divertors in bright spiral shapes. The responsible mechanism(s) has not yet been identified but may include fast-wave propagation in the scrape off layer, parametric decay instability, and RF currents driven by the antenna reactive fields. Understanding and mitigating these losses is important not only for improving the heating and current-drive on NSTX-Upgrade but also for understanding fast-wave propagation across the SOL in any fast-wave system. This talk summarizes experimental results demonstrating that the flow of lost HHFW power to the divertor regions largely follows the open SOL magnetic field lines. This lost power flux is relatively large close to both the antenna and the last closed flux surface with a reduced level in between, so the loss mechanism cannot be localized to the antenna. At the same time, significant losses also occur along field lines connected to the inboard edge of the bottom antenna plate. The power lost within the spirals is roughly estimated, showing that these field-aligned losses to the divertor are significant but may not account for the total HHFW loss. To elucidate the role of the onset layer for perpendicular fast-wave propagation with regards to fast-wave propagation in the SOL, a cylindrical cold-plasma model is being developed. This model, in addition to advanced RF codes such as TORIC and AORSA, is aimed at identifying the underlying mechanism(s) behind these SOL losses, to minimize their effects in NSTX-U, and to predict their importance in ITER.

Perkins, R. J.↗
DOE OSTI2014

Method of fabricating vertically aligned group III-V nanowires

A top-down method of fabricating vertically aligned Group III-V micro- and nanowires uses a two-step etch process that adds a selective anisotropic wet etch after an initial plasma etch to remove the dry etch damage while enabling micro/nanowires with straight and smooth faceted sidewalls and controllable diameters independent of pitch. The method enables the fabrication of nanowire lasers, LEDs, and solar cells.

36 MATERIALS SCIENCE↗
DOE OSTI2013

System and method for aligning heliostats of a solar power tower

Disclosed is a solar power tower heliostat alignment system and method that includes a solar power tower with a focal area, a plurality of heliostats that each reflect sunlight towards the focal area of the solar power tower, an off-focal area location substantially close to the focal area of the solar power tower, a communication link between the off-focal area location and a misaligned heliostat, and a processor that interprets the communication between the off-focal area location and the misaligned heliostat to identify the misaligned heliostat from the plurality of heliostats and that determines a correction for the identified misaligned heliostat to realign the misaligned heliostat to reflect sunlight towards the focal area of the solar power tower.

14 SOLAR ENERGY↗
DOE OSTI2015

Scaling Up Renewable Energy Generation: Aligning Targets and Incentives with Grid Integration Considerations, Greening The Grid

Greening the Grid provides technical assistance to energy system planners, regulators, and grid operators to overcome challenges associated with integrating variable renewable energy into the grid. This document, part of a Greening the Grid toolkit, provides power system planners with tips to help secure and sustain investment in new renewable energy generation by aligning renewable energy policy targets and incentives with grid integration considerations.

24 POWER TRANSMISSION AND DISTRIBUTION↗
DOE OSTI2012

AIMFAST: Alignment Implementation for Manufacturing

AIMFAST is a software code used to align facets on a dish concentrator to a specific aimpoint strategy to minimize peak fluxes and maximize system optical performance. AIMFAST uses a large monitor or projections screen to display fringe patterns, and a machine vision camera to image the reflection of these patterns in the subject dish mirrors. From these images, a detailed map of surface normals can be generated and compared to design or fitted mirror shapes. This fitted comparison is then used to develop a single vector representing the orientation of the facets relative to the design orientation, and provide near-real-time adjustment information to a communicating computer. The communicating computer can display adjustments or directly interface with adjustment tools. The software for the communicating computer is specific to the implementation and is not a part of AIMFAST.

Source record↗
DOE OSTI2016

Preparation of aligned nanotube membranes for water and gas separation applications

Fabrication methods for selective membranes that include aligned nanotubes can advantageously include a mechanical polishing step. The nanotubes have their ends closed off during the step of infiltrating a polymer precursor around the nanotubes. This prevents polymer precursor from flowing into the nanotubes. The polishing step is performed after the polymer matrix is formed, and can open up the ends of the nanotubes.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2016

Vehicle to wireless power transfer coupling coil alignment sensor

A non-contacting position sensing apparatus includes at least one vehicle-mounted receiver coil that is configured to detect a net flux null when the vehicle is optimally aligned relative to the primary coil in the charging device. Each of the at least one vehicle-mounted receiver coil includes a clockwise winding loop and a counterclockwise winding loop that are substantially symmetrically configured and serially connected to each other. When the non-contacting position sensing apparatus is located directly above the primary coil of the charging device, the electromotive forces from the clockwise winding loop and the counterclockwise region cancel out to provide a zero electromotive force, i.e., a zero voltage reading across the coil that includes the clockwise winding loop and the counterclockwise winding loop.

24 POWER TRANSMISSION AND DISTRIBUTION↗
DOE OSTI2016

Transducer-actuator systems and methods for performing on-machine measurements and automatic part alignment

Systems and methods for performing on-machine measurements and automatic part alignment, including: a measurement component operable for determining the position of a part on a machine; and an actuation component operable for adjusting the position of the part by contacting the part with a predetermined force responsive to the determined position of the part. The measurement component consists of a transducer. The actuation component consists of a linear actuator. Optionally, the measurement component and the actuation component consist of a single linear actuator operable for contacting the part with a first lighter force for determining the position of the part and with a second harder force for adjusting the position of the part. The actuation component is utilized in a substantially horizontal configuration and the effects of gravitational drop of the part are accounted for in the force applied and the timing of the contact.

42 ENGINEERING↗
DOE OSTI2013

IAIMFAST: Alignment Implementation for Manufacturing

AIMFAST is a software code used to align facets on a dish concentrator to a specific aimpoint strategy to minimize peak fluxes and maximize system optical performance. AIM FAST uses a large monitor to display fringe patterns, and a machine vision camera to image the reflection of these patterns in the subject dish mirrors. From these images, a detailed map of surface normals can be generated and compared to design or fitted mirror shapes. This fitted comparison is then used to develop a single vector representing the orientation of the facets relative to the design orientation, and provide near-real-time adjustment information to a communicating computer. The communicating computer can display adjustments or directly interface with adjustment tools.

Andraka, Charles E.↗
DOE OSTI2016

System and method for detecting components of a mixture including tooth elements for alignment

Examples are described including assay platforms having tooth elements. An impinging element may sequentially engage tooth elements on the assay platform to sequentially align corresponding detection regions with a detection unit. In this manner, multiple measurements may be made of detection regions on the assay platform without necessarily requiring the starting and stopping of a motor.

42 ENGINEERING↗
DOE OSTI2015

Evaluation of Power Supply and Alignment Tolerances for the Advanced Photons Source Upgrade

A hybrid seven-bend-achromat lattice that features very strong focusing elements and provides an electron beam with very low emittance has been proposed for the Advanced Photon Source upgrade [1,2]. In order to be able to maintain stable operation, tight tolerances are required for various types of errors. Here we describe evaluation of the effects of various errors including magnet power supplies, alignment, and vibration.

Sajaev, V.↗