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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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65 records · Page 4
All sourcesNASA NTRSDOE OSTI
NASA NTRS2007

A Radical Pathway for Organic Phosphorylation during Schreibersite Corrosion with Implications for the Origin of Life

Phosphorylated compounds (e.g. DNA, RNA, phospholipids, and many coenzymes) are critical to biochemistry. Thus, their origin is of prime interest to origin of life studies. The corrosion of the meteoritic mineral schreibersite ((Fe,Ni)3P) may have significantly contributed to the origin of phosphorylated biomolecules. Corrosion of synthetic schreibersite in a variety of solutions was analyzed by nuclear magnetic resonance spectroscopy, mass spectrometry, and electron paramagnetic resonance spectroscopy. These methods suggest a radical reaction pathway for the corrosion of schreibersite to form phosphite radicals (raised dot PO3 sup 2-)) aqueous solution. These radicals can form activated polyphosphates and can phosphorylate organic compounds such as acetate (3% yield). Phosphonates (O3P-C) are found in the organic P inventory of the carbonaceous meteorite Murchison. While phosphonates are rare in biochemistry, the ubiquity of corroding iron meteorites on the early Earth could have provided an accessible source of organophosphorous for the origin of life allowing the invention of the organophosphates in modern biology as a product of early evolution.

Pasek, Matthew A.↗
NASA NTRS1992

Production and characterization of monoclonal antibodies to budgerigar fledgling disease virus major capsid protein VP

Eleven hybridoma cell lines producing monoclonal antibodies (MAbs) against intact budgerigar fledgling disease (BFD) virions were produced and characterized. These antibodies were selected for their ability to react with BFD virions in an enzyme-linked immunosorbent assay. Each of these antibodies was reactive in the immunofluorescent detection of BFD virus-infected cells. These antibodies immunoprecipitated intact virions and specifically recognized the major capsid protein, VP1, of the dissociated virion. The MAbs were found to preferentially recognize native BFD virus capsid protein when compared with denatured virus protein. These MAbs were capable of detecting BFD virus protein in chicken embryonated cell-culture lysates by dot-blot analysis.

Non-NASA Center↗
NASA NTRS2004

Using Redundancy To Reduce Errors in Magnetometer Readings

A method of reducing errors in noisy magnetic-field measurements involves exploitation of redundancy in the readings of multiple magnetometers in a cluster. By "redundancy"is meant that the readings are not entirely independent of each other because the relationships among the magnetic-field components that one seeks to measure are governed by the fundamental laws of electromagnetism as expressed by Maxwell's equations. Assuming that the magnetometers are located outside a magnetic material, that the magnetic field is steady or quasi-steady, and that there are no electric currents flowing in or near the magnetometers, the applicable Maxwell 's equations are delta x B = 0 and delta(raised dot) B = 0, where B is the magnetic-flux-density vector. By suitable algebraic manipulation, these equations can be shown to impose three independent constraints on the values of the components of B at the various magnetometer positions. In general, the problem of reducing the errors in noisy measurements is one of finding a set of corrected values that minimize an error function. In the present method, the error function is formulated as (1) the sum of squares of the differences between the corrected and noisy measurement values plus (2) a sum of three terms, each comprising the product of a Lagrange multiplier and one of the three constraints. The partial derivatives of the error function with respect to the corrected magnetic-field component values and the Lagrange multipliers are set equal to zero, leading to a set of equations that can be put into matrix.vector form. The matrix can be inverted to solve for a vector that comprises the corrected magnetic-field component values and the Lagrange multipliers.

Kulikov, Igor↗
NASA NTRS2000

Reflective Focused Schlieren System Improved for Use in 10- by 10-Foot Supersonic Wind Tunnel

The reflective focused schlieren system that was developed for use in the 10- by 10-Foot Supersonic Wind Tunnel (10x10 SWT) at the NASA Glenn Research Center at Lewis Field as part of the Unstart Test Program was improved this past year. In April 1999, the development and use of the system was presented at the Supersonic Tunnel Association International in Bedford, England. A focused schlieren system is similar to a standard schlieren system in that shock waves coming from an object in supersonic flow can be seen using a standard video camera. Unlike the standard schlieren system, which produces a two-dimensional schlieren image, a focused schlieren system can produce a threedimensional image. The preceding drawing shows the components of the reflective focused schlieren system being developed for use in the 10x10 SWT. Although the system worked well for the Unstart Test Program, it was not sensitive enough to be classified as a facility capability. Therefore, a program was implemented to improve the sensitivity of the reflective focused schlieren system so that it could be a facility capability for Glenn's 10x10 SWT. Several techniques were implemented to increase the sensitivity and to improve the overall operation of the system. These included refinement of the source grid, improvement in the cutoff grid production, improvement of the source grid and cutoff grid alignment, installation of an improved light source, and incorporation of an image-enhancing system. These changes are being implemented with the system set up in the laboratory. A checkout test of the system is planned in the 10x10 SWT in March 2000. Of these techniques, the most developed is the refinement of the source grid. The original system had a pattern of -in. by -in. squares on -in. centers (distance between the center points of adjacent squares). This gave a ratio of light to dark (reflective to nonreflective area) of 3:1. The recommended ratio is 1:1. In order to accomplish this, a pattern of -in.-diameter dots on 3/8-in. centers was developed. Preliminary tests with this pattern showed an increase in system sensitivity and image clarity. Further testing and refinement are scheduled. The former and improved dot patterns are shown. The use of glass plates to produce the cutoff grid improved the cutoff grid's quality and helped to align it with the source grid. The cutoff grid, which is the negative of the source grid, is made by exposing photography film (or glass plates) to the proper light while it is installed in the focused schlieren system. The exposed film or plate is removed from the system and then developed as a photograph negative. Because the glass plates are rigid, they eliminate the risk of distortion when the negative is reinstalled in the system and realigned with the source grid.

Williamson, Gary Scott↗
NASA NTRS1997

Novel Highly Parallel and Systolic Architectures Using Quantum Dot-Based Hardware

VLSI technology has made possible the integration of massive number of components (processors, memory, etc.) into a single chip. In VLSI design, memory and processing power are relatively cheap and the main emphasis of the design is on reducing the overall interconnection complexity since data routing costs dominate the power, time, and area required to implement a computation. Communication is costly because wires occupy the most space on a circuit and it can also degrade clock time. In fact, much of the complexity (and hence the cost) of VLSI design results from minimization of data routing. The main difficulty in VLSI routing is due to the fact that crossing of the lines carrying data, instruction, control, etc. is not possible in a plane. Thus, in order to meet this constraint, the VLSI design aims at keeping the architecture highly regular with local and short interconnection. As a result, while the high level of integration has opened the way for massively parallel computation, practical and full exploitation of such a capability in many applications of interest has been hindered by the constraints on interconnection pattern. More precisely. the use of only localized communication significantly simplifies the design of interconnection architecture but at the expense of somewhat restricted class of applications. For example, there are currently commercially available products integrating; hundreds of simple processor elements within a single chip. However, the lack of adequate interconnection pattern among these processing elements make them inefficient for exploiting a large degree of parallelism in many applications.

Fijany, Amir↗
NASA NTRS1993

The fundamentals and futures of removable mass storage alternatives

This article reflects my view of how the storage products have been introduced into the marketplace, where they came from, and where others will continue to come from in the future. My corporate goal is to be a resource for those searching for removable solutions to mass storage problems. My introduction to optical storage occurred a few months before signing a non-disclosure agreement with FileNet on 8 Aug. 1983. By 87 or 88, as the optical craze was getting more popular, I started looking for similar or complementary storage technologies. I am still looking and my research is constantly turning up new entrants into this field. Due to the scope of the coverage in this field, this article does not dwell on any single technology. The goal is to provide information that is not compiled in any other single source and focus on facts that are not commonly known. I have provided a few baseline assumptions to ensure the mathematical calculations remain consistent: (1) hard-copy 8.5 in x 11 in documents which are scanned at 200 dots per inch (dpi) and compressed at a ratio of 10:1 result in a document image which requires an average of 50 Kilobytes (KB) of storage; (2) an average ASCII page requires 2 KB of storage; (3) an average flle cabinet drawer can hold 2500 pieces of paper; (4) one GB of storage can hold an average of 20,000 document images (a reel of 6250 tape holds 180 Megabytes (MB)).

Kempster, Linda↗
NASA NTRS2019

Acoustic Phased Array Quantification of Quiet Technology Demonstrator 3 Advanced Inlet Liner Noise Component

Acoustic phased array flyover noise measurements were acquired as part of the Boeing 737 MAX-7 NASA Advanced Inlet Liner segment of the Quiet Technology Demonstrator 3 (QTD3) flight test program. This paper reports on the processes used for separating and quantifying the engine inlet, exhaust and airframe noise source components and provides sample phased array-based comparisons of the component noise source levels associated with the inlet liner treatment configurations. Full scale flyover noise testing of NASA advanced inlet liners was conducted as part of the Quiet Technology Demonstrator 3 flight test program in July and August of 2018. Details on the inlet designs and testing are provided in the companion paper of Reference 1. The present paper provides supplemental details relating to the acoustic phased array portion of the analyses provided in Ref. 1. In brief, the test article was a Boeing 737MAX-7 aircraft with a modified right hand (starboard side) engine inlet, which consisted of either a production inlet liner, a NASA designed inlet liner or a simulated hard wall configuration (accomplished by applying speed tape over the inlet acoustic treatment areas). In all three configurations, the engine forward fan case acoustic panel was replaced with a unperforated (hardwall) panel. No other modifications to any other acoustic treatment areas were made. The left hand (port side) engine was a production engine and was flown at idle thrust for all measurements in order to isolate the effects of the inlet liners to the right hand engine. As described in Ref. 1, the NASA inlet treatment consists of laterally cut slots (cut perpendicular to the flow direction) which are designed to reduce excrescence drag while maintaining or exceeding the liner acoustic noise reduction capabilities. The NASA inlet liner consists of a Multi-Degree of Freedom (MDOF) design with two breathable septum layers inserted into each honeycomb cell [1]. The aircraft noise measurements were acquired for both takeoff (flaps 1 setting, gear up) and approach (flaps 30 gear up and gear down) configurations. The inlet and flight test configurations are summarized in Table 1. Table 1: Inlet Treatment and Flight Configurations Inlet Forward Fan Case Aircraft Production Hardwall Flaps 1, gear up; flaps 30 gear up; flaps 30 gear down NASA Hardwall Flaps 1, gear up; flaps 30 gear up; flaps 30 gear down Hardwall Hardwall Flaps 1, gear up; flaps 30 gear up; flaps 30 gear down III.Test Description and Hardware The flight testing was conducted at the Grant County airport in Moses Lake, WA, between 27 July and 6 August 2018. The noise measurement instrumentation included 8 flush dish microphones arranged in a noise certification configuration as well as an 840 microphone phased array. The flush dish microphones were used to quantify the levels and differences in levels between the various inlet treatments. The phased array was used to separate and quantify the narrowband (tonal) and broadband noise component levels from the engine inlet/exhaust and from the airframe. Phased array extraction of the broadband component was critical to this study because it allowed for the separation of the inlet component from the total airplane level noise even when it was significantly below the total level. Figure 1 provides an overview of the phased array microphone layout as well as a detailed image of an individual phased array microphone mounted in a plate holder (the microphone sensor is the dot in the center of the plate). The ground plane ensemble array microphones (referred to as “ensemble array” in this paper) were mounted in plates with “flower petal” edges designed to minimize edge scattering effects. Fig. 1 Flyover test microphone layout. The phased array configuration was the result of a progressive development of concepts originally implemented in Ref. 2 and refined over the following years, consisting namely of multiple multi-arm logarithmic spiral subarrays designed to cover overlapping frequency ranges and optimized for various aircraft emission angles. For the present case, the signals from all 840 microphones were acquired on a single system. The 840 microphones were parsed into 11 primary subarray sets spanning from smallest to largest aperture size and labeled accordingly as “a, b, …, k”, where “a” corresponds to the smallest fielded subarray and “k” corresponds to the largest aperture subarray. The apertures ranged from approximately 10 ft to 427 ft in size (in the flight direction) with the subarrays consisting of between 215 and 312 microphones. Figure 2 shows three such subarrays, k, h and a. As done in Ref. 2, microphones were shared between subarrays in order to reduce total channel count. Fig. 2 Sample subarray sizes (20° from overhead – refer to Figure 3a discussion). In addition to the above, each of the 11 primary subarray sets consisted of four subarrays optimized to provide near equivalent array spatial resolution in both the flight and lateral directions within 30 degrees of overhead (i.e., airplane directly above the center of the array), namely, at angles  of 0, ±10, ±20 and ±30 degrees relative to overhead where angle  is defined as shown in Figure 3a. This allowed for optimized aircraft noise measurements from 60 to 120 degree emission angle.6 An example of this pletharray design is shown in Figure 3b for the k subarray. When the aircraft is at overhead, the microphones indicated by the blue markers are used for beamforming. When the aircraft is at angles ±10 degrees from overhead, both the blue and red colored microphones are used, and so on for the ±20 and ±30 degree aircraft locations. See Ref. 3 for extensive details on pletharray design for aeroacoustic phased array testing. 6 In the discussions that follow, emission angle values are used. These are the angles at the time sound is emitted relative to the engine axis and are calculated based on flight path angle, body aircraft body angle with respect to the relative wind direction, and engine axis angle relative to aircraft body angle.

Brusniak, Leon↗
NASA NTRS2022

SpaceVPX Interoperability Assessment

The existing VMEbus (VersaModular Eurocard bus) International Trade Association (VITA)-78 industry standard, also known as SpaceVPX, is an avionics board- and chassis-level standard derived from the OpenVPX standard as defined in VITA-65. While VITA-65 defines backplane and board-level profiles from COTS vendors to ensure interoperability of products used in developing systems and subsystems, the VITA-78 standard defines SpaceVPX to incorporate fault tolerance features that are required by many spaceflight systems. However, VITA-78 allows so much flexibility that interoperability between modules cannot be assured. This assessment provides guidelines on the use of, and extensions to, the VITA-78 standard to enable avionics interoperability for future NASA missions. The assessment team was comprised of subject matter experts (SMEs) from Goddard Space Flight Center (GSFC), the Jet Propulsion Laboratory (JPL), Johnson Space Center (JSC), and Langley Research Center (LaRC). The team included valuable external consulting support from a SME who was a key participant in the development of the VITA-78 standard. The team had extensive collaboration with the NASA Space Technology Mission Directorate (STMD) High Performance Spaceflight Computing (HPSC) project, specifically in the development of SpaceVPX interconnect findings, observations, and NESC recommendations. To provide an understanding of the breadth of implementations that SpaceVPX must accommodate, multiple NASA use cases were analyzed to assess the requirements for SpaceVPX implementations across a wide range of NASA missions (Appendix C). Applications included crewed missions, science missions, and orbital and surface robotic systems. Product surveys were conducted to assess the level of industry support for SpaceVPX, applications, and the variations in their implementations (Appendix D). In-depth analysis was conducted in the areas of: (a) power management and distribution, (b) form factors and daughtercards, (c) interconnect, and (d) fault tolerance. Leveraging the use cases, product surveys, and SMEs from multiple NASA Centers, these areas were analyzed to determine the range of implementations permitted by the VITA-78 standard and potential interoperability issues. Applicable findings and NESC recommendations were provided for each area. During this assessment, there were multiple opportunities to engage with other agencies to learn about their interest in SpaceVPX, their strategies for implementing SpaceVPX-based systems, and their internal development efforts. These engagements also generated findings and NESC recommendations. Based on this assessment analysis, NESC recommendations were made regarding the feature set and module profiles to support NASA SpaceVPX implementations. This feature set includes restrictions on features in VITA-78, and extensions to the standard. Key recommendations in this area include the use of 10 Gigabit Ethernet and Peripheral Component Interconnect Express (PCIe) as high bandwidth interconnect on the backplane, the retention of SpaceWire interconnect for control functions, and support for 3U (unit) and 6U, form factors for NASA systems. Restrictions were proposed on the usage of user-defined signals to promote interoperability, and specific power managements and distribution schemes for 3U systems. Beyond the technical implementation of SpaceVPX, recommendations were made on areas that warrant further investigation. Primary among these is the recommendation for NASA to collaborate with other space-going agencies and industry to incorporate recommendations into a future ‘dot spec’ of VITA-78. This would ensure wide adoption and availability of the modules that comply with the specification. The assessment includes appendices with candidate module profiles that can be considered as a starting point for this activity, and example systems based on the recommendations. Follow-on studies are recommended for architectures beyond SpaceVPX to address potential enhancements including condensed set of interconnect, software required to implement protocol layers on the interconnect (and other features), alternative power architectures, and system-level testability.

SpaceVPX↗
NASA NTRS1994

The hard X-ray emission spectra from accretion columns in intermediate polars

We consider the hard (greater than 2 keV) X-ray emission from accretion columns in an intermediate polar system, GK Per, using a simple settling solution. The rate of photon emission per logarithmic energy interval can be fitted with a power law, E(exp -gamma), with gamma approximately 2.0, in agreement with observations. This index is only weakly dependent on the mass accretion rate, dot-M, for dot-M in the range of a few times 10(exp 16-18) g/s. The peak energy of the photon spectra (after photoelectric absorption) is expected to be E(sub p) approximately (5 keV) gamma(exp -1/3) (N(sub H)/10(exp 23)/sq cm)(exp 1/3) where N(sub H) is the hydrogen column density along the line of sight. The observed spectra of GK Per and possibly of V1223 Sgr suggest N(sub H) approximately 10(exp 23)/sq cm. This large N(sub H) may be due to partially ionized preshock column material. Alternatively, we also consider absorption by the cool outer parts of an accretion disk. In this case the photoelectric absorption depth in the disk is a sensitive function of inclination. For GK Per the required inclination is approximately 83 deg. For mass accretion rates larger than a critical rate of approximately 10(exp 18) g/s, X-ray emission from the column accretion is significantly affected by radiation drag. Although the mass accretion rate increases dramatically during outbursts, the observed hard (greater than 2 keV) X-ray luminosity will not rise proportionately. The slope and peak energy of the outburst spectra are only weakly affected. We conclude that the observed X-ray spectra can be explained by this simple analytic solution and that the production of hard X-rays from the accretion shock at the magnetic poles in the intermediate polars is in general agreement with the observations. However, since the X-ray emission and absorption depend on the mass accretion rate in a complicated manner, observed hard X-ray luminosities (greater than 2 keV) are not a good indicator of the mass accretion rate in the X-ray emitting regions.

Yi, Insu↗
NASA NTRS2018

Rapid Model Import Tool (RMIT)

Our project is about developing a tool to implement conversion of 3D Computer Aided Design (CAD) models produced with software such as Delmia, 3DS Max, or Maya, into a size and format compatible with the Unity 3D environment. RMIT will be used to aid KSC engineering personnel in the design, development, testing, operations, and training on spacecraft, launch vehicles, facilities, and ground support equipment. For our project, we are using Blender, a free/open-source 3D graphics software, with the goal of developing, testing, and deploying a 3D CAD model converter tool. I worked on using Blender to import 3D CAD models exported from CATIA software into Collada file format. The Collada file format has file extension DAE. Importing the Collada DAE file as is into Blender, generates dots and dashes. In 3DS Max, there is an existing OpenCollada plugin and with that plugin, 3DS Max can import the DAE file successfully. But, Blender does not seem to have an OpenCollada plugin, so I worked on writing a new OpenCollada plugin for Blender. Since 3DS Max was able to display the image, I looked into comparing differences between the original DAE file and the DAE file exported from 3DS Max using the OpenCollada plugin. As Collada documents describing digital assets are XML files with file extension DAE, Collada files contains XML tags, making them easily modifiable. After some research, it appears that Blender does not like primitive 2D tags like tristrips and trifans. Changing those tags to polygons slightly improved the image, but the pieces were exploded. I found after further research comparing differences between the original file and the file exported from 3DS Max that the values inside the translate tags in the original file are scaled down by a factor of 25.4 in the exported file from 3DS Max, representing the millimeters to inches conversion (1 inch = 25.4 millimeters). After scaling down values inside all of the translate tags by 25.4, the exploded pieces stuck back in, but the image needed further improvement. I have been able to create a new plugin in Blender that takes the original DAE file, replaces the primitive 2D tags tristrips and trifans with polygons, scales down the values inside the translate tags by a factor of 25.4, and saves the changes into a temporary DAE file. After the temporary DAE file is imported into Blender, the temp file is then deleted, keeping the original DAE file intact. Starting with a DAE file that is exported using the NASA Enterprise Visualization Application (NEVA), a Collada exporter, from CATIA gives better results. NEVA is a Design Visualization product that is used for exporting 3D models from CATIA. With NEVA, the up axis is defined in the top-level node if navigation gravity is enabled. With that file, just replacing the primitive tags tristrips and trifans with polygons in yields a much improved image in Blender. As we identify more differences between the original DAE file and the DAE file exported from 3DS Max, this plugin can be improved further. Our goal is to have a model that is formatted and sized for import into Unity, and we are trying out different 3D programs to see which will work best.

Ayyangar, Arjun↗
NASA NTRS2004

New Effective Material Couple--Oxide Ceramic and Carbon Nanotube-- Developed for Aerospace Microsystem and Micromachine Technologies

The prime driving force for using microsystem and micromachine technologies in transport vehicles, such as spacecraft, aircraft, and automobiles, is to reduce the weight, power consumption, and volume of components and systems to lower costs and increase affordability and reliability. However, a number of specific issues need to be addressed with respect to using microsystems and micromachines in aerospace applications--such as the lack of understanding of material characteristics; methods for producing and testing the materials in small batches; the limited proven durability and lifetime of current microcomponents, packaging, and interconnections; a cultural change with respect to system designs; and the use of embedded software, which will require new product assurance guidelines. In regards to material characteristics, there are significant adhesion, friction, and wear issues in using microdevices. Because these issues are directly related to surface phenomena, they cannot be scaled down linearly and they become increasingly important as the devices become smaller. When microsystems have contacting surfaces in relative motion, the adhesion and friction affect performance, energy consumption, wear damage, maintenance, lifetime and catastrophic failure, and reliability. Ceramics, for the most part, do not have inherently good friction and wear properties. For example, coefficients of friction in excess of 0.7 have been reported for ceramics and ceramic composite materials. Under Alternate Fuels Foundation Technologies funding, two-phase oxide ceramics developed for superior high-temperature wear resistance in NASA's High Operating Temperature Propulsion Components (HOTPC) project and new two-layered carbon nanotube (CNT) coatings (CNT topcoat/iron bondcoat/quartz substrate) developed in NASA's Revolutionary Aeropropulsion Concepts (RAC) project have been chosen as a materials couple for aerospace applications, including micromachines, in the nanotechnology lubrication task because of their potential for superior friction and wearf properties in air and in an ultrahigh vacuum, spacelike environment. At the NASA Glenn Research Center, two-phase oxide ceramic eutectics, Al2O3/ZrO2(Y2O3), were directionally solidified using the laser-float-zone process, and carbon nanotubes were synthesized within a high-temperature tube furnace at 800 C. Physical vapor deposition was used to coat all quartz substrates with 5-nm-thick iron as catalyst and bondcoat, which formed iron islands resembling droplets and serving as catalyst particles on the quartz. A series of scanning electron micrographs showing multiwalled carbon nanotubes directionally grown as aligned "nanograss" on quartz is presented. Unidirectional sliding friction eperiments were conducted at Glenn with the two-layered CNT coatings in contact with the two-phase Al2O3/ZrO2(Y2O3) eutectics in air and in ultrachigh vacuum. The main criteria for judging the performance of the materials couple for solid lubrication and antistick applications in a space environment were the coefficient of friction and the wear resistance (reciprocal of wear rate), which had to be less than 0.2 and greater than 10(exp 5) N(raised dot)/cubic millimetes, respectively, in ultrahigh vacuum. In air, the coefficient of friction for the CNT coatings in contact with Al2O3/ZrO2 (Y2O3) eutectics was 0.04, one-fourth of that for quartz. In an ultrahigh vacuum, the coefficient of friction for CNT coatings in contact with Al2O3/ZrO2 (Y2O3) was one-third of that for quartz. The two-phase Al2O3/ZrO2 (Y2O3) eutectic coupled with the two-layered CNT coating met the coefficient of friction and wear resistance criteria both in air and in an ultrahigh vacuum, spacelike environment. This material's couple can dramatically improve the stiction (or adhesion), friction, and wear resistance of the contacting surfaces, which are major issues for microdevices and micromachines.

Miyoshi, Kazuhisa↗