ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    facet.materialart.
    Unknown
    Shock-boundary-layer interaction in flight (1989)
    In:  CASI
    Details
    Publication Date: 2013-08-31
    Description: A brief survey is given on the study of transonic shock/boundary layer effects in flight. Then the possibility of alleviating the adverse shock effects through passive shock control is discussed. A Swedish flight experiment on a swept wing attack aircraft is used to demonstrate how it is possible to reduce the extent of separated flow and increase the drag-rise Mach number significantly using a moderate amount of perforation of the surface.
    Keywords: AERODYNAMICS
    Type: NASA, Langley Research Center, Transonic Symposium: Theory, Application, and Experiment, Volume 1, Part 1; p 61-77
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 2
    facet.materialart.
    Unknown
    Prediction of High-Lift Flows using Turbulent Closure Models (1997)
    In:  CASI
    Details
    Publication Date: 2018-06-05
    Description: The flow over two different multi-element airfoil configurations is computed using linear eddy viscosity turbulence models and a nonlinear explicit algebraic stress model. A subset of recently-measured transition locations using hot film on a McDonnell Douglas configuration is presented, and the effect of transition location on the computed solutions is explored. Deficiencies in wake profile computations are found to be attributable in large part to poor boundary layer prediction on the generating element, and not necessarily inadequate turbulence modeling in the wake. Using measured transition locations for the main element improves the prediction of its boundary layer thickness, skin friction, and wake profile shape. However, using measured transition locations on the slat still yields poor slat wake predictions. The computation of the slat flow field represents a key roadblock to successful predictions of multi-element flows. In general, the nonlinear explicit algebraic stress turbulence model gives very similar results to the linear eddy viscosity models.
    Keywords: Aerodynamics
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 3
    facet.materialart.
    Unknown
    Flight test results of riblets at supersonic speeds (1992)
    In:  CASI
    Details
    Publication Date: 2019-06-28
    Description: A flight experiment to test and evaluate the skin friction drag characteristics of a riblet surface in turbulent flow at supersonic speeds was conducted at NASA Dryden. Riblets of groove sizes 0.0030 and 0.0013 in. were mounted on the F-104G flight test fixture. The test surfaces were surveyed with boundary layer rakes and pressure orifices to examine the boundary layer profiles and pressure distributions of the flow. Skin friction reductions caused by the riblet surface were reported based on measured differences of momentum thickness between the smooth and riblet surfaces obtained from the boundary layer data. Flight test results for the 0.0030 in. riblet show skin friction reductions of 4 to 8 % for Mach numbers ranging from 1.2 to 1.6 and Reynolds numbers ranging from 2 to 3.4 million per unit foot. The results from the 0.0013 in. riblets show skin friction reductions of 4 to 15 % for Mach 1.2 to 1.4 and Reynolds numbers ranging from 3.6 to 6 million per unit foot.
    Keywords: AERODYNAMICS
    Type: NASA-TM-4387 , H-1774 , NAS 1.15:4387
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 4
    facet.materialart.
    Unknown
    Development of a system for transition characterization (1993)
    In:  Other Sources
    Details
    Publication Date: 2019-06-28
    Description: The present system for real-time boundary layer transition detection and characterization encompasses aerodynamic simulations, sensor characteristics, and a hybrid analog/digital system for signal analysis, verification, and compression. By using artificial, intermittently laminar/turbulent signals, in conjunction with trajectory simulation, it becomes possible to conduct algorithm development which is independent of, and in advance of, sensor buildup. Attention is given to the illustrative case of the Pegasus launch vehicle's trajectory.
    Keywords: INSTRUMENTATION AND PHOTOGRAPHY
    Type: AIAA PAPER 93-3465 , In: AIAA Applied Aerodynamics Conference, 11th, Monterey, CA, Aug. 9-11, 1993, Technical Papers. Pt. 1 (A93-47201 19-02); p. 510-523.
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 5
    facet.materialart.
    Unknown
    Use of piezoelectric foil for flow diagnostics (1989)
    In:  Other Sources
    Details
    Publication Date: 2019-07-27
    Description: A laboratory investigation was conducted to characterize two piezoelectric-film sensor configurations, a rigidly mounted sensor and a sensor mounted over an air cavity. The sensors are evaluated for sensitivity and frequency response, and methods to optimize data are presented. The cavity-mounted sensor exhibited a superior frequency response and was more sensitive to normal pressure fluctuations and less sensitive to vibrations through the structure. Both configurations were sensitive to large-scale structural vibrations. Flight-test data are shown for cavity-mounted sensors, illustrating practical aspects to consider when designing sensors for application in such harsh environments. The relation of the data to skin friction and maximum shear stress, transition detection, and turbulent viscous layers is derived through analysis of the flight data.
    Keywords: INSTRUMENTATION AND PHOTOGRAPHY
    Type: ICIASF ''89; Sept. 18-21, 1989; Goettingen; Germany
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 6
    facet.materialart.
    Unknown
    NASA LaRC FIB Multi-Channel Anemometry Recording System-User's Manual (2002)
    In:  CASI
    Details
    Publication Date: 2019-07-10
    Description: This report is part of a series of reports describing a flow physics high-lift experiment conducted in NASA Langley Research Center's Low-Turbulence Pressure Tunnel (LTPT) in 1996. The anemometry system used in the experiment was originally designed for and used in flight tests with NASA's Boeing 737 airplane. Information that may be useful in the evaluation or use of the experimental data has been compiled. The report also contains details regarding record structure, how to read the embedded time code, as well as the output file formats used in the code reading the binary data.
    Keywords: Fluid Mechanics and Thermodynamics
    Type: NASA/CR-2002-211440 , NAS 1.26:211440
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 7
    facet.materialart.
    Unknown
    3-D High-Lift Flow-Physics Experiment - Transition Measurements (2005)
    In:  CASI
    Details
    Publication Date: 2019-07-13
    Description: An analysis of the flow state on a trapezoidal wing model from the NASA 3-D High Lift Flow Physics Experiment is presented. The objective of the experiment was to characterize the flow over a non-proprietary semi-span three-element high-lift configuration to aid in assessing the state of the art in the computation of three-dimensional high-lift flows. Surface pressures and hot-film sensors are used to determine the flow conditions on the slat, main, and flap. The locations of the attachments lines and the values of the attachment line Reynolds number are estimated based on the model surface pressures. Data from the hot-films are used to determine if the flow is laminar, transitional, or turbulent by examining the hot-film time histories, statistics, and frequency spectra.
    Keywords: Aerodynamics
    Type: AIAA Paper 2005-5148 , AIAA Fluid Dynamics Conference and Exhibit; Jun 06, 2005 - Jun 09, 2005; Toronto, Ontario; Canada
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 8
    facet.materialart.
    Unknown
    Design and Calibration of an Airborne Multichannel Swept-Tuned Spectrum Analyzer (1999)
    In:  CASI
    Details
    Publication Date: 2019-07-13
    Description: This paper describes the design and calibration of a four-channel, airborne, swept-tuned spectrum analyzer used in two hypersonic flight experiments for characterizing dynamic data up to 25 kHz. Built mainly from commercially available analog function modules, the analyzer proved useful for an application with limited telemetry bandwidth, physical weight and volume, and electrical power. The authors discuss considerations that affect the frequency and amplitude calibrations, limitations of the design, and example flight data.
    Keywords: Avionics and Aircraft Instrumentation
    Type: NASA/TM-1999-206584 , H-2361 , NAS 1.15:206584 , Telmetering: Meeting The 21st Century Challenge; Oct 25, 1999 - Oct 28, 1999; Las Vegas, NV; United States
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 9
    facet.materialart.
    Unknown
    Pegasus(Registered trademark) Wing-Glove Experiment to Document Hypersonic Crossflow Transition: Measurement System and Selected Flight Results (2000)
    In:  CASI
    Details
    Publication Date: 2019-07-13
    Description: In a recent flight experiment to study hypersonic crossflow transition, boundary layer characteristics were documented. A smooth steel glove was mounted on the first stage delta wing of Orbital Sciences Corporation's Pegasus (R) launch vehicle and was flown at speeds of up to Mach 8 and altitudes of up to 250,000 ft. The wing-glove experiment was flown as a secondary payload off the coast of Florida in October 1998. This paper describes the measurement system developed. Samples of the results obtained for different parts of the trajectory are included to show the characteristics and quality of the data. Thermocouples and pressure sensors (including Preston tubes, Stanton tubes, and a "probeless" pressure rake showing boundary layer profiles) measured the time-averaged flow. Surface hot-films and high-frequency pressure transducers measured flow dynamics. Because the vehicle was not recoverable, it was necessary to design a system for real-time onboard processing and transmission. Onboard processing included spectral averaging. The quality and consistency of data obtained was good and met the experiment requirements.
    Keywords: Avionics and Aircraft Instrumentation
    Type: NASA/TM-2000-209016 , NAS 1.15:209016 , H-2395 , AIAA Paper 2000-0505 , 38th Aerospace Sciences; Jan 10, 2000 - Jan 13, 2000; Reno, NV; United States
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 10
    facet.materialart.
    Unknown
    Computational and experimental studies of LEBUs at high device Reynolds numbers (1988)
    In:  Other Sources
    Details
    Publication Date: 2019-07-13
    Description: The present paper summarizes computational and experimental studies for large-eddy breakup devices (LEBUs). LEBU optimization (using a computational approach considering compressibility, Reynolds number, and the unsteadiness of the flow) and experiments with LEBUs at high Reynolds numbers in flight are discussed. The measurements include streamwise as well as spanwise distributions of local skin friction. The unsteady flows around the LEBU devices and far downstream are characterized by strain-gage measurements on the devices and hot-wire readings downstream. Computations are made with available time-averaged and quasi-stationary techniques to find suitable device profiles with minimum drag.
    Keywords: AERODYNAMICS
    Type: IUTAM Symposium on Turbulence Management and Relaminarisation; Jan 13, 1987 - Jan 23, 1987; Bangalore; India
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...