Download or read book Three Component Doppler Global Velocimeter Measurements of the Flow Above a Delta Wing written by James F. Meyers and published by . This book was released on 1992 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt: A new measurement technique is being developed by NASA to measure off-surface flow fields. This method, Doppler global velocimetry, will allow qualification of complex three-dimensional flow fields at video camera rates. The entire flow field structure within a selected plane is measured simultaneously rather than by scanned, point-by-point measurements using conventional laser velocimetry. To assess the capability of this new technique, three component velocity measurements of the vortical flow field above a thin 75 degree delta wing were made in the NASA Langley Basic Aerodynamics Research Tunnel. Measurements were made of the flow field at the 70-percent chord locations at angles-of-attack of 20.5-and 40.0-degrees to investigate unburst and burst vortices. For comparison, previous fringe-type laser velocimeter measurements of the flow field at the same conditions are included.
Download or read book Doppler Global Velocimeter Measurements of the Vortical Flow Above a Thin Delta Wing written by Jimmy W. Usry and published by . This book was released on 1992 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Doppler Global Velocimetry written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-08-17 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt: A new measurement technique is being developed by NASA to measure off-surface flow fields. This method, Doppler global velocimetry, will allow quantification of complex three-dimensional flow fields at video camera rates. The entire flow field structure within a selected plane is measured simultaneously rather than by scanned, point-by-point measurements using conventional laser velocimetry. To assess the capability of this new technique, velocity measurements of the vortical flow field above a thin 75-degree delta wing were made in the NASA Langley Basic Aerodynamics Research Tunnel. The operation of the system is described along with the techniques developed to process the output images. The results are then compared with similar measurements obtained using a three component laser velocimeter. Meyers, James F. Langley Research Center ...
Download or read book Doppler Global Velocimetry Measurements for Supersonic Flow Fields written by James F. Meyers and published by BiblioGov. This book was released on 2013-07 with total page 22 pages. Available in PDF, EPUB and Kindle. Book excerpt: The application of Doppler Global Velocimetry (DGV) to high-speed flows has its origins in the original development of the technology by Komine et al (1991). Komine used a small shop-air driven nozzle to generate a 200 m/s flow. This flow velocity was chosen since it produced a fairly large Doppler shift in the scattered light, resulting in a significant transmission loss as the light passed through the Iodine vapor. This proof-of-concept investigation showed that the technology was capable of measuring flow velocity within a measurement plane defined by a single-frequency laser light sheet. The effort also proved that velocity measurements could be made without resolving individual seed particles as required by other techniques such as Fringe- Type Laser Velocimetry and Particle Image Velocimetry. The promise of making planar velocity measurements with the possibility of using 0.1-micron condensation particles for seeding, Dibble et al (1989), resulted in the investigation of supersonic jet flow fields, Elliott et al (1993) and Smith and Northam (1995) - Mach 2.0 and 1.9 respectively. Meyers (1993) conducted a wind tunnel investigation above an inclined flat plate at Mach 2.5 and above a delta wing at Mach 2.8 and 4.6. Although these measurements were crude from an accuracy viewpoint, they did prove that the technology could be used to study supersonic flows using condensation as the scattering medium. Since then several research groups have studied the technology and developed solutions and methodologies to overcome most of the measurement accuracy limitations.
Download or read book Modelling Fluid Flow written by János Vad and published by Springer Science & Business Media. This book was released on 2013-04-17 with total page 424 pages. Available in PDF, EPUB and Kindle. Book excerpt: Modelling Fluid Flow presents invited lectures, workshop summaries and a selection of papers from a recent international conference CMFF '03 on fluid technology. The lectures follow the current evolution and the newest challenges of the computational methods and measuring techniques related to fluid flow. The workshop summaries reflect the recent trends, open questions and unsolved problems in the mutually inspiring fields of experimental and computational fluid mechanics. The papers cover a wide range of fluids engineering, including reactive flow, chemical and process engineering, environmental fluid dynamics, turbulence modelling, numerical methods, and fluid machinery.
Download or read book Doppler Global Velocimetry Development of a Flight Research Instrumentation System for Application to Non intrusive Measurements of the Flow Field written by and published by . This book was released on 1994 with total page 110 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Detailed Flow field Measurements Over a 75 swept Delta Wing written by Scott O. Kjelgaard and published by . This book was released on 1990 with total page 52 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Advanced Aerodynamic Measurement Technology written by North Atlantic Treaty Organization. Advisory Group for Aerospace Research and Development. Fluid Dynamics Panel. Symposium and published by . This book was released on 1998 with total page 444 pages. Available in PDF, EPUB and Kindle. Book excerpt: The demands for higher performance for modern aircraft have led the wind tunnel community, which is an integral link in the design process, to develop more refined and cost effective measuring techniques. These technologies have gradually matured from laboratory novelties into instruments regularly used in aerodynamic testing. The development of these modern measurement techniques has greatly extended the capability and accuracy of the classical methods for measurement techniques and provided better insight into flow physics. This Symposium provided a forum for active researchers to address the state-of-the-art, to exchange experiences and ideas, and for the practitioners to obtain an overview of the technology and learn how to appy it.
Download or read book Detailed Flow Field Measurements Over a 75 Deg Swept Delta Wing written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-07 with total page 46 pages. Available in PDF, EPUB and Kindle. Book excerpt: Results from an experimental investigation documenting the flowfield over a 75 deg swept delta wing at an angle-of-attack of 20.5 deg are presented. Results obtained include surface flow visualization, off-body flow visualization, and detailed flowfield surveys for various Reynolds numbers. Flowfield surveys at Reynolds numbers of 0.5, 1.0, and 1.5 million based on the root chord were conducted with both a Pitot pressure probe and a 5-hole pressure probe; and 3-component laser velocimeter surveys were conducted at a Reynolds number of 1.0 million. The Pitot pressure surveys were obtained at 5 chordwise stations, the 5-hole probe surveys were obtained at 3 chordwise stations and the laser velocimeter surveys were obtained at one station. The results confirm the classical roll up of the flow into a pair of primary vortices over the delta wing. The velocity measurements indicate that Reynolds number has little effect on the global structure of the flowfield for the Reynolds number range investigated. Measurements of the non-dimensional axial velocity in the core of the vortex indicate a jet like flow with values greater than twice freestream. Comparisons between velocity measurements from the 5-hole pressure probe and the laser velocimeter indicate that the pressure probe does a reasonable job of measuring the flowfield quantities where the velocity gradients in the flowfield are low. Kjelgaard, Scott O. and Sellers, William L., III Langley Research Center RTOP 505-60-11-03...
Download or read book 31st Aerospace Sciences Meeting and Exhibit 93 0410 93 0449 written by and published by . This book was released on 1993 with total page 628 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Laser Techniques and Applications in Fluid Mechanics written by Ronald J. Adrian and published by . This book was released on 1993 with total page 554 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book 29th AIAA Fluid Dynamics Conference written by and published by . This book was released on 1998 with total page 460 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Proceedings of the ASME Fluids Engineering Division Summer Meeting written by American Society of Mechanical Engineers. Fluids Engineering Division. Summer Meeting and published by . This book was released on 1996 with total page 680 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book AIAA Journal written by American Institute of Aeronautics and Astronautics and published by . This book was released on 2005 with total page 960 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Applied Mechanics Reviews written by and published by . This book was released on 1987 with total page 338 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Doppler Global Velocimetry Development of a Flight Research Instrumentation System for Application to Non Intrusive Measurements of the Flow Fiel written by National Aeronautics and Space Adm Nasa and published by Independently Published. This book was released on 2018-10-27 with total page 56 pages. Available in PDF, EPUB and Kindle. Book excerpt: Doppler Global Velocimetry (DGV) is a new diagnostic tool that offers potential for flow field measurements in flight by acquiring three-component velocity data in near real-time during flight maneuvers. The feasibility of implementation of a flight DGV system aboard NASA's High-Angle-of-Attack Research Vehicle (HARV) was addressed in this work by identifying the essential characteristics of a flight measurement system and by performing calibration and error tests. Results from this work were: an outline that establishes a preliminary basis for system configurations by analyzing measurement errors, installation issues, and operating requirements; measurement of the accuracy of the DGV technique using a laboratory breadboard DGV system based on a frequency-doubled Nd: YAG laser and iodine Absorption Line Filter (ALF), which showed excellent agreement between the DGV data and pilot measurements on a laminar flow jet with velocities of up to 150 m/sec; a survey of DGV system components and technologies that are relevant to the design of a flight measurement system, including a survey of cameras for the next generation DGV receivers; an assessment of the candidate lasers and absorption line filters for the flight system, resulting in a near-term recommendation of Nd: host lasers and an iodine ALF for both flight and wind tunnel applications. Komine, Hiroshi and Brosnan, Stephen J. and Long, William H. and Stappaerts, Eddy A. Unspecified Center...
Download or read book Theoretical and Applied Mechanics Report written by and published by . This book was released on 1996 with total page 432 pages. Available in PDF, EPUB and Kindle. Book excerpt:
