Institution
Langley Research Center
Facility•Hampton, Virginia, United States•
About: Langley Research Center is a facility organization based out in Hampton, Virginia, United States. It is known for research contribution in the topics: Mach number & Wind tunnel. The organization has 15945 authors who have published 37602 publications receiving 821623 citations. The organization is also known as: NASA Langley & NASA Langley Research Center.
Topics: Mach number, Wind tunnel, Aerodynamics, Boundary layer, Supersonic speed
Papers published on a yearly basis
Papers
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TL;DR: In this paper, it was shown that interactions between powerful solar flares and Earth's magnetic field could have facilitated nitrogen fixation in the early atmosphere, which is needed to convert N2 into compounds essential for life.
Abstract: An energetic process is needed to convert N2 into compounds essential for life Simulations show that interactions between powerful solar flares and Earth’s magnetic field could have facilitated nitrogen fixation in the early atmosphere
243 citations
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Goddard Space Flight Center1, Universities Space Research Association2, University of Miami3, University of Maryland, Baltimore County4, University of Maryland, College Park5, Goddard Institute for Space Studies6, Columbia University7, University of Hawaii8, Pacific Marine Environmental Laboratory9, Langley Research Center10, Argonne National Laboratory11, National Oceanic and Atmospheric Administration12
TL;DR: In this article, the authors analyzed aerosol variations and trends over different land and ocean regions from 1980 to 2009 with the Goddard Chemistry Aerosol Radiation and Transport (GOCART) model and observations from multiple satellite sensors and available ground-based networks.
Abstract: . Aerosol variations and trends over different land and ocean regions from 1980 to 2009 are analyzed with the Goddard Chemistry Aerosol Radiation and Transport (GOCART) model and observations from multiple satellite sensors and available ground-based networks. Excluding time periods with large volcanic influence, aerosol optical depth (AOD) and surface concentration over polluted land regions generally vary with anthropogenic emissions, but the magnitude of this association can be dampened by the presence of natural aerosols, especially dust. Over the 30-year period in this study, the largest reduction in aerosol levels occurs over Europe, where AOD has decreased by 40–60% on average and surface sulfate concentrations have declined by a factor of up to 3–4. In contrast, East Asia and South Asia show AOD increases, but the relatively high level of dust aerosols in Asia reduces the correlation between AOD and pollutant emission trends. Over major dust source regions, model analysis indicates that the change of dust emissions over the Sahara and Sahel has been predominantly driven by the change of near-surface wind speed, but over Central Asia it has been largely influenced by the change of the surface wetness. The decreasing dust trend in the North African dust outflow region of the tropical North Atlantic and the receptor sites of Barbados and Miami is closely associated with an increase of the sea surface temperature in the North Atlantic. This temperature increase may drive the decrease of the wind velocity over North Africa, which reduces the dust emission, and the increase of precipitation over the tropical North Atlantic, which enhances dust removal during transport. Despite significant trends over some major continental source regions, the model-calculated global annual average AOD shows little change over land and ocean in the past three decades, because opposite trends in different land regions cancel each other out in the global average, and changes over large open oceans are negligible. This highlights the necessity for regional-scale assessment of aerosols and their climate impacts, as global-scale average values can obscure important regional changes.
243 citations
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04 Jan 2016TL;DR: In this paper, a single-aisle commercial transport concept with a turbo-electric propulsion system architecture was developed assuming entry into service in 2035 and compared to a similar technology conventional configuration.
Abstract: A single-aisle commercial transport concept with a turboelectric propulsion system architecture was developed assuming entry into service in 2035 and compared to a similar technology conventional configuration. The turboelectric architecture consisted of two underwing turbofans with generators extracting power from the fan shaft and sending it to a rear fuselage, axisymmetric, boundary layer ingesting fan. Results indicate that the turbo- electric concept has an economic mission fuel burn reduction of 7%, and a design mission fuel burn reduction of 12% compared to the conventional configuration. An exploration of the design space was performed to better understand how the turboelectric architecture changes the design space, and system sensitivities were run to determine the sensitivity of thrust specific fuel consumption at top of climb and propulsion system weight to the motor power, fan pressure ratio, and electrical transmission efficiency of the aft boundary layer ingesting fan.
243 citations
01 Aug 1980
TL;DR: Three new options were incorporated into an existing computer program for the design and analysis of low speed airfoils that permit the analysis of airfoil having variable chord (variable geometry), a boundary layer displacement iteration, and theAnalysis of the effect of single roughness elements.
Abstract: A conformal mapping method for the design of airfoils with prescribed velocity distribution characteristics, a panel method for the analysis of the potential flow about given airfoils, and a boundary layer method have been combined With this combined method, airfoils with prescribed boundary layer characteristics can be designed and airfoils with prescribed shapes can be analyzed All three methods are described briefly The program and its input options are described A complete listing is given as an appendix
240 citations
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20 Jun 1994239 citations
Authors
Showing all 16015 results
Name | H-index | Papers | Citations |
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Daniel J. Jacob | 162 | 656 | 76530 |
Donald R. Blake | 118 | 727 | 49697 |
Veerabhadran Ramanathan | 100 | 301 | 47561 |
Raja Parasuraman | 91 | 402 | 41455 |
Robert W. Platt | 88 | 638 | 31918 |
James M. Russell | 87 | 691 | 29383 |
Daniel J. Inman | 83 | 918 | 37920 |
Antony Jameson | 79 | 474 | 31518 |
Ya-Ping Sun | 79 | 277 | 28722 |
Patrick M. Crill | 79 | 228 | 20850 |
Richard B. Miles | 78 | 759 | 25239 |
Patrick Minnis | 77 | 490 | 23403 |
Robert W. Talbot | 77 | 297 | 19783 |
Raphael T. Haftka | 76 | 773 | 28111 |
Jack E. Dibb | 75 | 344 | 18399 |