Download or read book A Comparison of Interactional Aerodynamics Methods for a Helicopter in Low Speed Flight written by John D. Berry and published by . This book was released on 1998 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt: Recent advances in computing subsonic flow have been applied to helicopter configurations with various degrees of success. This paper is a comparison of two specific methods applied to a particularly challenging regime of helicopter flight, very low speeds, where the interaction of the rotor wake and the fuselage are most significant. Comparisons are made between different methods of predicting the interactional aerodynamics associated with a simple generic helicopter configuration. These comparisons are made using fuselage pressure data from a Mach-scaled powered model helicopter with a rotor diameter of approximately 3 meters. The data shown are for an advance ratio of 0.05 with a thrust coefficient of 0.0066. The results of this comparison show that in this type of complex flow both analytical techniques have regions where they are more accurate in matching the experimental data.
Download or read book A Comparison of Interactional Aerodynamics Methods for a Helicopter in Low Speed Flight written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-08-09 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt: Recent advances in computing subsonic flow have been applied to helicopter configurations with various degrees of success. This paper is a comparison of two specific methods applied to a particularly challenging regime of helicopter flight, very low speeds, where the interaction of the rotor wake and the fuselage are most significant. Comparisons are made between different methods of predicting the interactional aerodynamics associated with a simple generic helicopter configuration. These comparisons are made using fuselage pressure data from a Mach-scaled powered model helicopter with a rotor diameter of approximately 3 meters. The data shown are for an advance ratio of 0.05 with a thrust coefficient of 0.0066. The results of this comparison show that in this type of complex flow both analytical techniques have regions where they are more accurate in matching the experimental data. Berry, John D. and Letnikov, Victor and Bavykina, Irena and Chaffin, Mark S. Unspecified Center NASA/TM-1998-208420, L-17732, NAS 1.15:208420, AFDD/TR-98-A-003 RTOP 581-10-11-01...
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1994 with total page 956 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Proceedings of the Fifth International Conference in Ocean Engineering ICOE2019 written by Vallam Sundar and published by Springer Nature. This book was released on 2020-11-08 with total page 551 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book comprises the proceedings of the Fifth International Conference in Ocean Engineering (ICOE2019) focusing on emerging opportunities and challenges in the field of ocean engineering and offshore structures. Some of the themes covered in this volume are offshore structures and deepwater technology, ocean optics & acoustics, ocean renewable energy, marine spatial planning, climate change impacts & disaster risk reduction, etc. The essays are written by leading international experts, making it a valuable resource for researchers and practicing engineers alike.
Download or read book NASA Langley Scientific and Technical Information Output 1997 written by and published by . This book was released on 1998 with total page 162 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Technical Abstract Bulletin written by and published by . This book was released on 1979 with total page 1186 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book NASA Langley Scientific and Technical Information Output 1998 written by and published by . This book was released on 1999 with total page 166 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Preliminary Study of a Model Rotor in Descent written by and published by . This book was released on 2000 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt: Within a program designed to develop experimental techniques for measuring the trajectory and structure of vortices trailing from the tips of rotor blades, the present preliminary study focuses on a method for quantifying the trajectory of the trailing vortex during descent flight conditions. This study also presents rotor loads and blade surface pressures for a range of tip-path plane angles and Mach numbers. Blade pressures near the leading edge and along the outer radius are compared with data obtained on the same model rotor, but in open jet facilities. A triangulation procedure based on two directable laser-light sheets, each containing an embedded reference, proved effective in defining the spatial coordinates of the trailing vortex. When interrogating a cross section of the flow that contains several trailing vortices, the greatest clarity was found to result when the flow is uniformly seeded. Surface pressure responses during blade-vortex interactions appeared equally sensitive near the leading edge and along the outer portion of the blade, but diminished rapidly as the distance along the blade chord increased. The pressure response was virtually independent of whether the tip-path plane angle was obtained through shaft tilt or cyclic pitch. Although the shape and frequency of the pressure perturbations on the advancing blade during blade-vortex interaction are similar to those obtained in open-jet facilities, the angle of the tip-path plane may need to be lower than the range covered in this study.
Download or read book Aeronautical Engineering written by and published by . This book was released on 1991 with total page 538 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Rotary Wing Aerodynamics written by W. Z. Stepniewski and published by Courier Corporation. This book was released on 2013-04-22 with total page 640 pages. Available in PDF, EPUB and Kindle. Book excerpt: DIVClear, concise text covers aerodynamic phenomena of the rotor and offers guidelines for helicopter performance evaluation. Originally prepared for NASA. Prefaces. New Indexes. 10 black-and-white photos. 537 figures. /div
Download or read book Principles of Helicopter Aerodynamics with CD Extra written by Gordon J. Leishman and published by Cambridge University Press. This book was released on 2006-04-24 with total page 860 pages. Available in PDF, EPUB and Kindle. Book excerpt: Written by an internationally recognized teacher and researcher, this book provides a thorough, modern treatment of the aerodynamic principles of helicopters and other rotating-wing vertical lift aircraft such as tilt rotors and autogiros. The text begins with a unique technical history of helicopter flight, and then covers basic methods of rotor aerodynamic analysis, and related issues associated with the performance of the helicopter and its aerodynamic design. It goes on to cover more advanced topics in helicopter aerodynamics, including airfoil flows, unsteady aerodynamics, dynamic stall, and rotor wakes, and rotor-airframe aerodynamic interactions, with final chapters on autogiros and advanced methods of helicopter aerodynamic analysis. Extensively illustrated throughout, each chapter includes a set of homework problems. Advanced undergraduate and graduate students, practising engineers, and researchers will welcome this thoroughly revised and updated text on rotating-wing aerodynamics.
Download or read book International Aerospace Abstracts written by and published by . This book was released on 1998 with total page 980 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Monthly Catalog of United States Government Publications written by and published by . This book was released on 1971 with total page 1388 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book NASA Scientific and Technical Publications written by and published by . This book was released on 1993 with total page 134 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book NASA SP written by and published by . This book was released on 1993 with total page 360 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Principles of Helicopter Aerodynamics written by J. Gordon Leishman and published by Cambridge University Press. This book was released on 2002-12-23 with total page 544 pages. Available in PDF, EPUB and Kindle. Book excerpt: Helicopters are highly capable and useful rotating-wing aircraft with roles that encompass a variety of civilian and military applications. Their usefulness lies in their unique ability to take off and land vertically, to hover stationary relative to the ground, and to fly forward, backward, or sideways. These unique flying qualities, however, come at a high cost including complex aerodynamic problems, significant vibrations, high levels of noise, and relatively large power requirements compared to fixed-wing aircraft. This book, written by an internationally recognized expert, provides a thorough, modern treatment of the aerodynamic principles of helicopters and other rotating-wing vertical lift aircraft. Every chapter is extensively illustrated and concludes with a bibliography and homework problems. Advanced undergraduate and graduate students, practising engineers, and researchers will welcome this thorough and up-to-date text on rotating-wing aerodynamics.
Download or read book Summary of Low Speed Airfoil Data written by Michael S. Selig and published by Soartech. This book was released on 1995 with total page 320 pages. Available in PDF, EPUB and Kindle. Book excerpt: