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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 199 records · Page 11
All sourcesNASA NTRSDOE OSTI
NASA NTRS2001

Baseline Testing of the EV Global E-Bike SX

The NASA John H. Glenn Research Center initiated baseline testing of the EV Global E-Bike SX as an update of the state of the art in hybrid electric bicycles. The E-bike is seen as a way to reduce pollution in urban areas, reduce fossil fuel consumption, and reduce operating costs for transportation systems. The work was done under the Hybrid Power Management (HPM) Program, which includes the Hybrid Electric Transit Bus (HETB). The SX is a high performance, state of the art, ground up, hybrid electric bicycle. Unique features of the SX's 36 V power system include the use of an efficient, 400 W, electric hub motor, and a seven-speed derailleur system that permits operation as fully electric, fully pedal, or a combination of the two. Other innovative features, such as regenerative braking through ultracapacitor energy storage, are planned. Regenerative braking recovers much of the kinetic energy of the vehicle during deceleration. The E-Bike is an inexpensive approach to advance the state of the art in hybrid technology in a practical application. The project transfers space technology to terrestrial use via nontraditional partners, and provides power system data valuable for future space applications. A description of the SX, the results of performance testing, and future vehicle development plans are given in this report. The report concludes that the SX provides excellent performance, and that the implementation of ultracapacitors in the power system can provide significant performance improvements.

Eichenherg, Dennis J.↗
NASA NTRS2003

The Data Acquisition and Controls Systems (DACS) of the E-Complex at the John C. Stennis Space Center, MS: A General Overview

The John C. Stennis Space Center (SSC) provides test operations services to a variety of customers including NASA, DoD, commercial enterprises, and others for the development of current next-generation rocket propulsion systems. Many of these test operations services are provided in the E-Complex series of test facilities. The E-Complex is composed of three active test stands (E1, E2, & E3), each with two or more test positions. Each test position is comprised of unique sets of data acquisition and controls hardware and software that record both facility and test article data and safely operate the test facility. The E-Complex data acquisition system (DAS) is actually composed of two separate systems, one for static data and the other for dynamic. The static DAS, otherwise known as the Low-Speed DAS (LSDAS), samples 16 bit data at 250 samples-per-second (SPS), although an aggregate sample rate of 200,000 SPS is possible. The dynamic data acquisition system, otherwise known as the high-speed DAS (HSDAS), samples 16 bit data at 100K SPS with a 45 KHz bandwidth.

Hughes, Mark S.↗
NASA NTRS1999

Gentamicin: effect on E. coli in space

Previous investigations have shown that liquid bacterial cultures grown in space flight were not killed as effectively by antibiotic treatments as were cultures grown on Earth. However, the cause for the decreased antibiotic effectiveness remains unknown. Possible explanations include modified cell proliferation and modified antibiotic transport in the culture medium. Escherichia coli cultures were grown in space flight (STS-69 and STS-73), with and without gentamicin, on a solid agar substrate thus eliminating fluid effects and reducing the unknowns associated with space-flight bacterial cultures in suspension. This research showed that E. coli cultures grown in flight on agar for 24 to 27 hours experienced a heightened growth compared to simultaneous controls. However, addition of gentamicin to the agar killed the bacteria such that both flight and ground control E. coli samples had similar final cell concentrations. Therefore, while the reported existence of a decrease in antibiotic effectiveness in liquid cultures remains unexplained, these data suggest that gentamicin in space flight was at least as effective as, if not more effective than, on Earth, when E. coli cells were grown on agar.

STS-69 Shuttle Project↗
NASA NTRS2003

EOS Aqua AMSR-E Arctic Sea Ice Validation Program: Arctic2003 Aircraft Campaign Flight Report

In March 2003 a coordinated Arctic sea ice validation field campaign using the NASA Wallops P-3B aircraft was successfully completed. This campaign was part of the program for validating the Earth Observing System (EOS) Aqua Advanced Microwave Scanning Radiometer (AMSR-E) sea ice products. The AMSR-E, designed and built by the Japanese National Space Development Agency for NASA, was launched May 4, 2002 on the EOS Aqua spacecraft. The AMSR-E sea ice products to be validated include sea ice concentration, sea ice temperature, and snow depth on sea ice. This flight report describes the suite of instruments flown on the P-3, the objectives of each of the seven flights, the Arctic regions overflown, and the coordination among satellite, aircraft, and surface-based measurements. Two of the seven aircraft flights were coordinated with scientists making surface measurements of snow and ice properties including sea ice temperature and snow depth on sea ice at a study area near Barrow, AK and at a Navy ice camp located in the Beaufort Sea. Two additional flights were dedicated to making heat and moisture flux measurements over the St. Lawrence Island polynya to support ongoing air-sea-ice processes studies of Arctic coastal polynyas. The remaining flights covered portions of the Bering Sea ice edge, the Chukchi Sea, and Norton Sound.

Cavalieri, D. J.↗
NASA NTRS2006

EOS Aqua AMSR-E Arctic Sea-Ice Validation Program: Arctic2006 Aircraft Campaign Flight Report

In March 2006, a coordinated Arctic sea-ice validation field campaign using the NASA Wallops P-3B aircraft was successfully completed. This campaign was the second Alaskan Arctic field campaign for validating the Earth Observing System (EOS) Aqua Advanced Microwave Scanning Radiometer (AMSR-E) sea-ice products. The first campaign was completed in March 2003. The AMSR-E, designed and built by the Japanese Space Agency for NASA, was launched May 4, 2002 on the EOS Aqua spacecraft. The AMSR-E sea-ice products to be validated include sea-ice concentration, sea-ice temperature, and snow depth on sea ice. The focus of this campaign was on the validation of snow depth on sea ice and sea-ice temperature. This flight report describes the suite of instruments flown on the P-3, the objectives of each of the six flights, the Arctic regions overflown, and the coordination among satellite, aircraft, and surface-based measurements.

Cavalieri, D. J.↗
NASA NTRS2007

E-Textile Antennas for Space Environments

The ability to integrate antennas and other radio frequency (RF) devices into wearable systems is increasingly important as wireless voice, video, and data sources become ubiquitous. Consumer applications including mobile computing, communications, and entertainment, as well as military and space applications for integration of biotelemetry, detailed tracking information and status of handheld tools, devices and on-body inventories are driving forces for research into wearable antennas and other e-textile devices. Operational conditions for military and space applications of wireless systems are often such that antennas are a limiting factor in wireless performance. The changing antenna platform, i.e. the dynamic wearer, can detune and alter the radiation characteristics of e-textile antennas, making antenna element selection and design challenging. Antenna designs and systems that offer moderate bandwidth, perform well with flexure, and are electronically reconfigurable are ideally suited to wearable applications. Several antennas, shown in Figure 1, have been created using a NASA-developed process for e-textiles that show promise in being integrated into a robust wireless system for space-based applications. Preliminary characterization of the antennas with flexure indicates that antenna performance can be maintained, and that a combination of antenna design and placement are useful in creating robust designs. Additionally, through utilization of modern smart antenna techniques, even greater flexibility can be achieved since antenna performance can be adjusted in real-time to compensate for the antenna s changing environment.

Kennedy, Timothy F.↗
NASA NTRS2007

Lunar e-Library: A Research Tool Focused on the Lunar Environment

As NASA plans and implements the Vision for Space Exploration, managers, engineers, and scientists need lunar environment information that is readily available and easily accessed. For this effort, lunar environment data was compiled from a variety of missions from Apollo to more recent remote sensing missions, such as Clementine. This valuable information comes not only in the form of measurements and images but also from the observations of astronauts who have visited the Moon and people who have designed spacecraft for lunar missions. To provide a research tool that makes the voluminous lunar data more accessible, the Space Environments and Effects (SEE) Program, managed at NASA's Marshall Space Flight Center (MSFC) in Huntsville, AL, organized the data into a DVD knowledgebase: the Lunar e-Library. This searchable collection of 1100 electronic (.PDF) documents and abstracts makes it easy to find critical technical data and lessons learned from past lunar missions and exploration studies. The SEE Program began distributing the Lunar e-Library DVD in 2006. This paper describes the Lunar e-Library development process (including a description of the databases and resources used to acquire the documents) and the contents of the DVD product, demonstrates its usefulness with focused searches, and provides information on how to obtain this free resource.

McMahan, Tracy A.↗
NASA NTRS2007

Empirical Storm-Time Correction to the International Reference Ionosphere Model E-Region Electron and Ion Density Parameterizations Using Observations from TIMED/SABER

The response of the ionospheric E-region to solar-geomagnetic storms can be characterized using observations of infrared 4.3 micrometers emission. In particular, we utilize nighttime TIMED/SABER measurements of broadband 4.3 micrometers limb emission and derive a new data product, the NO+(v) volume emission rate, which is our primary observation-based quantity for developing an empirical storm-time correction the IRI E-region electron density. In this paper we describe our E-region proxy and outline our strategy for developing the empirical storm model. In our initial studies, we analyzed a six day storm period during the Halloween 2003 event. The results of this analysis are promising and suggest that the ap-index is a viable candidate to use as a magnetic driver for our model.

Mertens, Christoper J.↗
NASA NTRS2009

Storm/Quiet Ratio Comparisons Between TIMED/SABER NO (sup +)(v) Volume Emission Rates and Incoherent Scatter Radar Electron Densities at E-Region Altitudes

Broadband infrared limb emission at 4.3 microns is measured by the TIMED/SABER instrument. At night, these emission observations at E-region altitudes are used to derive the so called NO+(v) Volume Emission Rate (VER). NO+(v) VER can be derived by removing the background CO2(v3) 4.3 microns radiance contribution using SABER-based non-LTE radiation transfer models, and by performing a standard Abel inversion on the residual radiance. SABER observations show that NO+(v) VER is significantly enhanced during magnetic storms in accordance with increased ionization of the neutral atmosphere by auroral electron precipitation, followed by vibrational excitation of NO+ (i.e., NO+(v)) from fast exothermic ion-neutral reactions, and prompt infrared emission at 4.3 m. Due to charge neutrality, the NO+(v) VER enhancements are highly correlated with electron density enhancements, as observed for example by Incoherent Scatter Radar (ISR). In order to characterize the response of the storm-time E-region from both SABER and ISR measurements, a Storm/Quiet ratio (SQR) quantity is defined as a function of altitude. For SABER, the SQR is the ratio of the storm-to-quiet NO+(v) VER. SQR is the storm-to-quiet ratio of electron densities for ISR. In this work, we compare SABER and ISR SQR values between 100 to 120 km. Results indicate good agreement between these measurements. SQR values are intended to be used as a correction factor to be included in an empirical storm-time correction to the International Reference Ionosphere model at E-region altitudes.

Fernandez, J. R.↗
NASA NTRS2012

High-latitude E Region Ionosphere-thermosphere Coupling: A Comparative Study Using in Situ and Incoherent Scatter Radar Observations

We present in situ and ground-based measurements of the ratio k of ion cyclotronangular frequency to ion-neutral momentum transfer collision frequency to investigateionosphere-thermosphere (IT) coupling in the auroral E region. In situ observations were obtained by NASA sounding rocket 36.234, which was launched into the nightsideE region ionosphere at 1229 UT on 19 January 2007 from Poker Flat, AK. The payload carried instrumentation to determine ion drift angle and electric field vectors. Neutral winds were measured by triangulating a chemical tracer released from rocket 41.064 launched two minutes later. k is calculated from the rotation of the ion drift angle relative to the E-cross-B drift direction in a frame co-rotating with the payload. Between the altitudes of 118 km and 130 km k increases exponentially with a scale height of 9.3 +/- 0.7 km, deviating from an exponential above 130 km. k = 1 at an altitude z(sub0) of 119.9 +/- 0.5 km. The ratio was also estimated from Poker Flat Incoherent Scatter Radar (PFISR) measurements using the rotation of ion velocity with altitude. Exponential fits to the PFISR measurements made during the flight of 41.064 yield z(sub0) 115.9 +/- 1.2 km and a scale height of 9.1 +/- 1.0 km. Differences between in situ and ground-based measurements show that the E region atmospheric densities were structured vertically and/or horizontally on scales of 1 km to 10 km. There were no signs of ionospheric structure in ion density or ion temperature below scales of 1 km. The observations demonstrate the accuracy with which the in situ and PFISR data may be used as probes of IT coupling.

Burchill, J. K.↗
NASA NTRS2016

Plasma Deflection Test Setup for E-Sail Propulsion Concept

The Electronic Sail or E-Sail is a novel propulsion concept based on momentum exchange between fast solar wind protons and the plasma sheath of long positively charged conductors comprising the E-Sail. The effective sail area increases with decreasing plasma density allowing an E-Sail craft to continue to accelerate at predicted ranges well beyond the capabilities of existing electronic or chemical propulsion spacecraft. While negatively charged conductors in plasmas have been extensively studied and flown, the interaction between plasma and a positively charged conductor is not well studied. We present a plasma deflection test method using a differential ion flux probe (DIFP). The DIFP measures the angle and energy of incident ions. The plasma sheath around a charged body can measured by comparing the angular distribution of ions with and without a positively charged test body. These test results will be used to evaluate numerical calculations of expected thrust per unit length of conductor in the solar wind plasma. This work was supported by a NASA Space Technology Research Fellowship.

Andersen, Allen↗
NASA NTRS2017

Overview of the Acoustic Testing of the European Service Module Structural Test Article (E-STA)

The European Space Agency (ESA) and their prime contractor Airbus Defense Space (ADS) are developing the European Service Module (ESM) for integration and utilization with other modules of NASAs Orion Multi-Purpose Crew Vehicle. As part of this development, ESA, ADS, NASA and the Lockheed Martin Company performed a series of reverberant acoustic tests in April-May 2016 on the ESM Structural Test Article (E-STA), the mechanical mock-up of the ESM designated for mechanical tests. Testing the E-STA under acoustic qualification loads verifies whether it can successfully withstand the medium and high frequency mechanical environment occurring during the vehicles lift-off and atmospheric phases of flight. The testing occurred at the Reverberant Acoustic Test Facility (RATF) at the NASA Glenn Research Centers Plum Brook Station site in Sandusky, OH, USA. This highly successful acoustic test campaign excited the E-STA to acoustic test levels as high as 149.4 dB Overall Sound Pressure Level. This acoustic testing met all the ESA and ADSs test objectives, including establishing/verifying the random vibration qualification test levels for numerous hardware components of the ESM, and qualifying the ESMs Solar Array Wing electrical power system. This paper will address the test objectives, the test articles configuration, the test instrumentation and excitation levels, the RATF site and capabilities, the series of acoustic tests performed, and the technical issues faced and overcome to result in a successful acoustic test campaign for the ESM. A discussion of several test results is also included.

Qualification↗
NASA NTRS2017

Overview of the Acoustic Testing of the European Service Module Structural Test Article (E-STA)

The European Space Agency (ESA) and their prime contractor Airbus Defense Space (ADS) are developing the European Service Module (ESM) for integration and utilization with other modules of NASAs Orion Multi-Purpose Crew Vehicle. As part of this development, ESA, ADS, NASA and the Lockheed Martin Company performed a series of reverberant acoustic tests in April-May 2016 on the ESM Structural Test Article (E-STA), the mechanical mock-up of the ESM designated for mechanical tests. Testing the E-STA under acoustic qualification loads verifies whether it can successfully withstand the medium and high frequency mechanical environment occurring during the vehicles lift-off and atmospheric phases of flight. The testing occurred at the Reverberant Acoustic Test Facility (RATF) at the NASA Glenn Research Centers Plum Brook Station site in Sandusky, OH, USA. This highly successful acoustic test campaign excited the E-STA to acoustic test levels as high as 149.4 dB Overall Sound Pressure Level. This acoustic testing met all the ESA and ADSs test objectives, including establishingverifying the random vibration qualification test levels for numerous hardware components of the ESM, and qualifying the ESMs Solar Array Wing electrical power system. This paper will address the test objectives, the test articles configuration, the test instrumentation and excitation levels, the RATF site and capabilities, the series of acoustic tests performed, and the technical issues faced and overcome to result in a successful acoustic test campaign for the ESM. A discussion of several test results is also included.

Testing↗
NASA NTRS2017

Overview of the Acoustic Testing of the European Service Module Structural Test Article (E-STA)

The European Space Agency (ESA) and their prime contractor Airbus Defense Space (ADS) are developing the European Service Module (ESM) for integration and utilization with other modules of NASAs Orion Multi-Purpose Crew Vehicle. As part of this development, ESA, ADS, NASA and the Lockheed Martin Company performed a series of reverberant acoustic tests in April-May 2016 on the ESM Structural Test Article (E-STA), the mechanical mock-up of the ESM designated for mechanical tests. Testing the E-STA under acoustic qualification loads verifies whether it can successfully withstand the medium and high frequency mechanical environment occurring during the vehicles lift-off and atmospheric phases of flight. The testing occurred at the Reverberant Acoustic Test Facility (RATF) at the NASA Glenn Research Centers Plum Brook Station site in Sandusky, OH, USA. This highly successful acoustic test campaign excited the E-STA to acoustic test levels as high as 149.4 dB Overall Sound Pressure Level. This acoustic testing met all the ESA and ADSs test objectives, including establishingverifying the random vibration qualification test levels for numerous hardware components of the ESM, and qualifying the ESMs Solar Array Wing electrical power system. This paper will address the test objectives, the test articles configuration, the test instrumentation and excitation levels, the RATF site and capabilities, the series of acoustic tests performed, and the technical issues faced and overcome to result in a successful acoustic test campaign for the ESM. A discussion of several test results is also included.

Qualification↗
NASA NTRS1977

Measurements of the reaction e/+/e/-/ yielding gamma-gamma at center-of-mass energies in the range 6.2-7.4 GeV

The cross section for the pair-annihilation reaction e(+)e(-) yields gamma-gamma were measured at center-of-mass energies in the range 6.2-7.4 GeV and at production angles close to 90 deg. The experimental apparatus consisted of two identical spectrometers which were set to view the luminous region at SPEAR-II from opposite directions at an azimuthal angle of 45 deg. In each spectrometer there was a NaI(TI) crystal 20 radiation lengths thick and 30 in. in diameter to measure the gamma-ray energies. Annihilation events were detected by an electronic trigger which required only the observation in coincidence of more than 0.2 GeV in each NaI(TI) crystal within + or - 15 nsec of the crossing beams. The observed rates of pair-annihilation events were found to be in agreement with those expected from quantum electrodynamics (QED) at all the center-of-mass energies used.

Hilger, E.↗
NASA NTRS1990

Observations of the flank of earth's bow shock to -110 R(E) by ISEE 3/ICE

The ISEE 3/ICE spacecraft made over 100 crossings of earth's bow shock between x(SEC) = -20 and -110 R(E) most of them further away than -60 R(E) while resetting its course for comet Giacobini-Zinner. The parameters of the crossings are tabulated and some of their magnetic, plasma wave, and spectral profiles at low magnetosonic Mach numbers are displayed. Loci of crossings are compared with the extrapolation of a model of earlier statistical success, showing that the model remains useful in the far flank.

Greenstadt, E. W.↗