Download or read book Experimental Investigation of Model Variable geometry and Ogee Tip Rotors written by Anton J. Landgrebe and published by . This book was released on 1974 with total page 124 pages. Available in PDF, EPUB and Kindle. Book excerpt: An experimental investigation was conducted to systematically explore the effects of inter-blade spatial relationships and pitch variations on rotor performance and wake geometry. Variable-geometry rotors consisting of various combinations of blade length, axial spacing, azimuth spacing, and collective pitch were tested at model scale in hover and forward flight. In addition, a hover test of a model rotor with an ogee blade tip design was conducted to determine its performance and wake characteristics. The results of this investigation indicate that properly selected variable geometry rotor configurations can offer substantial improvements in hover performance without adversely affecting forward flight performance. Axial spacing of alternate blades was found to provide the greatest performance benefit, and further improvements were achieved by combining azimuth spacing with axial spacing. The performance benefit appears to be related to the relief of local adverse aerodynamic phenomena produced by vortex interference. The ogee tip design was found to substantially reduce the concentrated core intensity of the tip vortex, and could thus prove beneficial for the relief of blade-vortex interaction problems. However, the ogee tip was found to reduce hover performance at model scale.
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1981 with total page 1370 pages. Available in PDF, EPUB and Kindle. Book excerpt: Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.
Download or read book NASA Technical Paper written by and published by . This book was released on 1979 with total page 86 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Survey of Theoretical and Experimental Coaxial Rotor Aerodynamic Research written by Colin P. Coleman and published by . This book was released on 1997 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Government Reports Announcements written by and published by . This book was released on 1974 with total page 964 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effect of Sweep Angle on the Pressure Distributions and Effectiveness of the Ogee Tip in Diffusing a Line Vortex written by John C. Balcerak and published by . This book was released on 1973 with total page 128 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book International Aerospace Abstracts written by and published by . This book was released on 1977 with total page 1196 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Proceedings of the NASA Industry University General Aviation Drag Reduction Workshop written by Jan Roskam and published by . This book was released on 1984 with total page 468 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book NASA Contractor Report written by and published by . This book was released on 1976 with total page 998 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Aeronautical Engineering written by and published by . This book was released on 1975 with total page 586 pages. Available in PDF, EPUB and Kindle. Book excerpt: A selection of annotated references to unclassified reports and journal articles that were introduced into the NASA scientific and technical information system and announced in Scientific and technical aerospace reports (STAR) and International aerospace abstracts (IAA).
Download or read book The Aeronautical Journal written by and published by . This book was released on 1974 with total page 356 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Hearings Reports and Prints of the Senate Select Committee on Small Business written by United States. Congress. Senate. Select Committee on Small Business and published by . This book was released on 1975 with total page 1440 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Technology and Management Assistance Programs of the Small Business Administration written by United States. Congress. Senate. Select Committee on Small Business and published by . This book was released on 1976 with total page 572 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Noise Suppression with High Mach Number Inlets written by Edward Lumsdaine and published by . This book was released on 1976 with total page 996 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book NASA Conference Publication written by and published by . This book was released on 1988 with total page 550 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Hover performance tests of full scale variable geometry rotors written by James B. Rorke and published by . This book was released on 1976 with total page 124 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Devices that Alter the Tip Vortex of a Rotor written by and published by . This book was released on 2001 with total page 230 pages. Available in PDF, EPUB and Kindle. Book excerpt: Small devices were attached near the tip of a hovering rotor blade in order to alter the structure and trajectory of the trailing vortex. Stereo particle image velocimetry (PIV) images were used to quantify the wake behind the rotor blade during the first revolution. A procedure for analyzing the 3D-velocity field is presented that includes a method for accounting for vortex wander. The results show that a vortex generator can alter the trajectory of the trailing vortex and that a major change in the size and intensity of the trailing vortex can be achieved by introducing a high level of turbulence into the core of the vortex.
