Download or read book Summary Report of the Development of a Laser Velocimeter to be Used in AEDC Wind Tunnels written by and published by . This book was released on 1970 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Development of a Laser Velocimeter to be Used in AEDC Wind Tunnels written by A. E. Lennert and published by . This book was released on 1970 with total page 201 pages. Available in PDF, EPUB and Kindle. Book excerpt: The report summarizes a three-year analytical and experimental program to develop a laser Doppler velocity (LDV) instrument for measuring velocities of flowing fluids. The electro-optical instruments are being developed for enhancing the measuring capabilities in the AEDC wind tunnels. The basic design parameters of the input-aligned optics LDV system and, in particular, the development of a self-aligning system to obviate the basic problems inherent with previously conceived systems, are described in detail. The design and the progress are presented on a direct readout system to determine directly three orthogonal components of velocity. A number of significant proof-of-principle experiments covering a wide variety of flows, both liquid and gaseous, are discussed. Included are the results of a V/STOL wind tunnel calibration study verifying the superior performance of the LDV for velocity determinations and boundary-layer measurements. (Author).
Download or read book Summary report of the development of a laser velocimeter to be used in AEDC wind tunnels written by ARO, Inc and published by . This book was released on 1970 with total page 374 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Velocity Measurements in the AEDC Low Speed Wind Tunnel V STOL Using a Laser Doppler Velocimeter written by F. H. Smith and published by . This book was released on 1970 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: An in-house developed laser Doppler velocimeter (LDV) was used to make velocity measurements in a low speed wind tunnel. The installation and instrumentation are discussed, and velocity profiles obtained with the LDV are compared with those obtained using conventional techniques. A discussion on the factors which affect the accuracy of the LDV and improvements that would be desirable are also included. (Author).
Download or read book Laser Velocimeter Optical Traverse Scheme An Investigation of a Proposed Optical Scanning Technique for Arnold Engineering and Development Center s Four Foot Transonic Wind Tunnel written by G. S. Krajci and published by . This book was released on 1983 with total page 141 pages. Available in PDF, EPUB and Kindle. Book excerpt: This investigation analyzed a nonstandard laser velocimeter setup proposed for use in AEDC Wind Tunnel 4T. The setup uses a gimballed mirror to move the probe volume from point to point, and the translation of a lens to control the distance in the tunnel the probe volume reaches. Results show that for equal indices of refraction inside and outside the tunnel, the laser beams of a converging pair do not totally converge with its associated beam except under certain conditions, and the probe volumes created by each pair of overlapping laser beams do not always coincide. This work then provides the conditions necessary for total convergence of a pair of laser beams for this setup. A solution is then proposed to insure convergence of each laser beam pair and overlap of the two probe volumes. More than a solution to the above problems, a method is given to determine the azimuth and elevation angles for a mirror such that the reflected beam off the mirror passes through a given point in the tunnel after traversing a window. To carry out these investigations, a computer code was written to simulate the nonstandard laser velocimeter setup, and a second code was written to determine the azimuth and elevation angles for a mirror such that the reflected beam off the mirror passes through a given point in the tunnel after traversing a window. Both codes were written in FORTRAN 77, implemented on a CDC 6000-CYBER 74.
Download or read book The Use of a Laser Doppler Velocimeter in Supersonic Flow written by William Joseph Yanta and published by . This book was released on 1971 with total page 64 pages. Available in PDF, EPUB and Kindle. Book excerpt: Results are presented for an experimental program which investigated the application of an LDV technique in supersonic flows. This paper presents an analysis of the behavior of light-scattering particles in rapidly accelerating or shock decelerated flows, an evaluation of particle production techniques and the results of several velocity measurements. Measurements included the velocity distribution along the nozzle centerline and flow over a diamond airfoil in a Mach 3 tunnel and velocity profiles for a turbulent boundary layer in a Mach 4.8 facility. It is demonstrated that LDV measurements can be made consistently with errors of less than five percent if the particle lag is considered. (Author).
Download or read book Transonic Wing store Flow field Measurement Using a Laser Velocimeter written by F. L. Heltsley and published by . This book was released on 1981 with total page 62 pages. Available in PDF, EPUB and Kindle. Book excerpt: A test was conducted in the Arnold Engineering Development Center (AEDC) Aerodynamic Wind Tunnel (1T) of the Propulsion Wind Tunnel Facility (PWT) to measure the flow fields about several wing/pylon/store configurations. Test models included a wall-mounted swept wing, five-percent MK-83 and M-117 stores, and swept and unswept pylons. Flow-field velocity measurements, made by using a three-component laser velocimeter, are presented. (Author).
Download or read book Laser Velocimetry in the Low speed Wind Tunnels at Ames Research Center written by and published by . This book was released on 1984 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Turbulence Measurements with a Laser Doppler Velocimeter written by William Joseph Yanta and published by . This book was released on 1973 with total page 104 pages. Available in PDF, EPUB and Kindle. Book excerpt: Turbulence measurements with a Laser Doppler Velocimeter (LDV) using the dual scatter or differential Doppler mode have been made in a subsonic, fully developed channel flow. The measurements were made using only those light scattering particles occurring naturally in air. Results include mean velocity profiles, turbulence intensities, Reynolds stress distributions and a skewness measurement of the velocity distribution function across the channel. Statistical techniques were used to obtain the various turbulence parameters. Guidelines have been established for the amount of data needed to obtain results with a specified accuracy and confidence level. Measurements have also been made to determine the particle-size distribution. An aerodynamic means was used to determine the size distribution, in contrast to the usual optical procedures. (Modified author abstract).
Download or read book Development and Utilization of a Laser Velocimeter System for a Large Transonic Wind Tunnel written by Robert J. Freedman and published by . This book was released on 1982 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Transonic Wing Store Flow Field Measurement Using a Laser Velocimeter written by F. L. Heltsley and published by . This book was released on 1981 with total page 57 pages. Available in PDF, EPUB and Kindle. Book excerpt: A test was conducted in the Arnold Engineering Development Center (AEDC) Aerodynamic Wind Tunnel (1T) of the Propulsion Wind Tunnel Facility (PWT) to measure the flow fields about several wing/pylon/store configurations. Test models included a wall-mounted swept wing, five-percent MK-83 and M-117 stores, and swept and unswept pylons. Flow-field velocity measurements, made by using a three-component laser velocimeter, are presented. (Author).
Download or read book Doppler Global Velocimeter Development for the Large Wind Tunnels at Ames Research Center written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-07-06 with total page 60 pages. Available in PDF, EPUB and Kindle. Book excerpt: Development of an optical, laser-based flow-field measurement technique for large wind tunnels is described. The technique uses laser sheet illumination and charged coupled device detectors to rapidly measure flow-field velocity distributions over large planar regions of the flow. Sample measurements are presented that illustrate the capability of the technique. An analysis of measurement uncertainty, which focuses on the random component of uncertainty, shows that precision uncertainty is not dependent on the measured velocity magnitude. For a single-image measurement, the analysis predicts a precision uncertainty of +/-5 m/s. When multiple images are averaged, this uncertainty is shown to decrease. For an average of 100 images, for example, the analysis shows that a precision uncertainty of +/-0.5 m/s can be expected. Sample applications show that vectors aligned with an orthogonal coordinate system are difficult to measure directly. An algebraic transformation is presented which converts measured vectors to the desired orthogonal components. Uncertainty propagation is then used to show how the uncertainty propagates from the direct measurements to the orthogonal components. For a typical forward-scatter viewing geometry, the propagation analysis predicts precision uncertainties of +/-4, +/-7, and +/-6 m/s, respectively, for the U, V, and W components at 68% confidence. Reinath, Michael S. Ames Research Center...
Download or read book Laser Velocimeter Optical Traverse Scheme written by Gary S. Krajci (CAPT, USAF.) and published by . This book was released on 1983 with total page 252 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Low velocity Airflow Calibration and Research Facility written by L. P. Purtell and published by . This book was released on 1979 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Transonic Wing Store Flow Field Measurement Using a Laser Velocimeter written by and published by . This book was released on 1981 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: A test was conducted in the Arnold Engineering Development Center (AEDC) Aerodynamic Wind Tunnel (1T) of the Propulsion Wind Tunnel Facility (PWT) to measure the flow fields about several wing/pylon/store configurations. Test models included a wall-mounted swept wing, five-percent MK-83 and M-117 stores, and swept and unswept pylons. Flow-field velocity measurements, made by using a three-component laser velocimeter, are presented. (Author).
Download or read book Design and Evaluation of a Laser Doppler Velocimeter for the AEDC PWT 4 Foot Transonic Tunnel written by F. L. Crosswy and published by . This book was released on 1978 with total page 62 pages. Available in PDF, EPUB and Kindle. Book excerpt: The design details and initial performance evaluation of a two-component Laser Doppler Velocimeter (LDV) system for a large transonic wind tunnel are presented. The two-color, backscatter LDV was specially developed for free-stream, pitch plane flow angle and velocity magnitude measurements using only intrinsic particulate matter as light scatterers. An environmental control system and remote optical alignment techniques were developed since the LDV was located in the hostile environment (vibration, vacuum, inaccessibility, etc.) of the tunnel plenum region. A new-type LDV signal processor was developed to process the low-level signals produced by the small intrinsic particles. A versatile, computer-based system was developed for high-speed data acquisition. LDV mean velocity and flow angle data are compared to free-stream velocity data and aerodynamic flow angle probe data. (Author).
Download or read book NASA Technical Note written by and published by . This book was released on 1976 with total page 450 pages. Available in PDF, EPUB and Kindle. Book excerpt:
