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Design Fabrication Test And Evaluation Of Small Scale Tiltrotor Whirl Flutter Wind Tunnel Models
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Book Synopsis Design, Fabrication, Test, and Evaluation of Small-scale Tiltrotor Whirl Flutter Wind Tunnel Models by : Guillermo Costa
Download or read book Design, Fabrication, Test, and Evaluation of Small-scale Tiltrotor Whirl Flutter Wind Tunnel Models written by Guillermo Costa and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The modern tiltrotor is an aircraft capable of efficient hover as well as high-speed forward flight. The large, flexible rotors needed for good hover performance are susceptible to an aeroelastic phenomenon known as whirl flutter in high-speed flight: high rotor inflow and the flexible nature of the rotors will result in negative aerodynamic damping when the tiltrotor is in airplane mode, causing the coupled wing/rotor/pylon system to become unstable. Traditionally, the tiltrotor whirl flutter margin has been increased through the use of thick wings of low aspect ratio, which maximize the stiffness of the wings at the expense of increased structural weight and reduced aerodynamic efficiency. To increase the top speed of tiltrotors, new methods of analyzing and mitigating the whirl flutter phenomenon must be developed.This study focuses on the design and development of a semispan wind tunnel model that permits the testing of whirl flutter stability in a controlled, low-risk environment. The wind tunnel model was dynamically tested in the Penn State Hammond Low-Speed Wind Tunnel. Five configurations were tested for modal damping variations with respect to tunnel speed. Two of these configurations ("Gen-2") were modified versions of the first-generation ("Gen-1") wind tunnel model designed and tested by S.C. Johnson in the 2012-2013 timeframe. Three configurations of an all-new model ("Gen-3") were developed to increase the realism of the test specimen, and included features such as tuned wing modal frequencies, higher-Lock number rotor blades, and blade twist. Most importantly, the Gen-3 models were designed to flutter without the use of an added mass or unconventional center of gravity placement. Gen-3 was developed through the use of an in-house computer code, which generated damping predictions for the wing modes at various tunnel speeds. Model components and support equipment were fabricated in-house by the author, with some components (e.g. those requiring computer-controlled machining) outsourced to local manufacturers. Wind tunnel tests were performed in the Hammond tunnel from October 2014 through January 2015; these tests showed that the experimentally-measured flutter speeds of the Gen-3 models were within 5-7% of the predicted values, with the Gen-3a (untwisted composite blades) fluttering at approximately 101 ft./sec., and the Gen-3b model (twisted composite blades) fluttering at approximately 97 ft./sec.The present work has further validated the feasibility of whirl flutter testing at a small scale. The Gen-3 model was able to exhibit whirl flutter without the use of an additional mass, and will permit the testing of devices designed to enhance the whirl flutter margin within the current facility. The techniques used to fabricate the Gen-3 model show potential for introducing features such as blade flexibility and an modular wing root flexure for a wider test regime.
Book Synopsis Whirl Flutter of Turboprop Aircraft Structures by : Jiří Čečrdle
Download or read book Whirl Flutter of Turboprop Aircraft Structures written by Jiří Čečrdle and published by Elsevier. This book was released on 2023-01-13 with total page 378 pages. Available in PDF, EPUB and Kindle. Book excerpt: Whirl Flutter of Turboprop Aircraft Structures, Second Edition explores the whirl flutter phenomenon, including theoretical, practical, analytical and experimental aspects of the matter. Sections provide a general overview regarding aeroelasticity, discussions on the physical principle and the occurrence of whirl flutter in aerospace practice, and experimental research conducted, especially from the 60s. Other chapters delve into analytical methods such as basic and advanced linear models, non-linear and CFD based methods, certification issues including regulation requirements, a description of possible certification approaches, and several examples of aircraft certification from aerospace. Finally, a database of relevant books, reports and papers is provided. This updated and expanded second edition covers new chapters including both analytical and experimental aspects of the subject matter. Provides complex information on turboprop aircraft whirl flutter phenomenon Presents both theoretical and practical (certification related) issues Includes experimental research as well as analytical models (basic and advanced) of matter Includes both early-performed works and recent developments Contains a listing of relevant books and reports
Book Synopsis Wind Tunnel Test Techniques by : Colin Britcher
Download or read book Wind Tunnel Test Techniques written by Colin Britcher and published by Academic Press. This book was released on 2023-10-20 with total page 672 pages. Available in PDF, EPUB and Kindle. Book excerpt: Wind Tunnel Test Techniques: Design and Use at Low and High Speeds with Statistical Engineering Applications provides an up-to-date treatment of the topic. Beginning with a brief history of wind tunnels and its types and uses, the book goes on to cover subsonic, supersonic and hypersonic wind tunnel design and construction, calibration, boundary corrections, flow quality assessment, pressure surveys, and dynamic testing. It also focuses on wind tunnel facilities, making it useful for both the designer and operator. Engineers and graduate students in aerospace, automotive and similar programs will find this book useful in their work with experimental aerodynamics, gas dynamics, facility design and performance. Deals with a broad range of flow speeds in wind tunnels, from low speed to high speed Provides a discussion of similarity laws as well as material on statistical analysis Includes coverage on facility-to-facility and facility-to-CFD correlation Presents advanced topics such as cryogenic wind tunnels, ground simulation in automotive testing, and propulsion testing
Book Synopsis Models for Wind Tunnel Tests Based on Additive Manufacturing Technology by : Weijun Zhu
Download or read book Models for Wind Tunnel Tests Based on Additive Manufacturing Technology written by Weijun Zhu and published by Springer Nature. This book was released on 2024-01-15 with total page 230 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book systematically introduces design and fabrication of physical models for wind tunnel tests based on additive manufacturing technology, including model design technology, model fabrication process, strengthening technology, etc. On this basis, it introduces in detail the specific implementation process of commonly used models, e.g., force measurement models, pressure measurement models, elastic models, and flutter models. This book mainly provides references for researchers and engineers who are engaged in aircraft design, experimental fluid mechanics, and additive manufacturing technology research.
Book Synopsis Design, Construction, and Testing of an Open-loop Low-speed Wind Tunnel by : Muhammad Adnin Mat Bahari
Download or read book Design, Construction, and Testing of an Open-loop Low-speed Wind Tunnel written by Muhammad Adnin Mat Bahari and published by . This book was released on 2012 with total page 67 pages. Available in PDF, EPUB and Kindle. Book excerpt: An open-loop low-speed wind tunnel is one of the easiest ways to study about aerodynamics for undergraduate studies. The objectives of this project are to propose a design with detail analysis, fabrication of a small scale open-loop low-speed wind tunnel and to validate the designed wind tunnel through performance testing with the existing instrumentations available in the laboratory. The wind tunnel was designed by considering the essential parts of the wind tunnel with the proper justifications before modelled with Computer Aided Design (CAD) and then tested using the Computational Fluid Dynamics (CFD). After obtaining the desired simulation result, the designed wind tunnel was fabricated and then followed by the test models. Then the wind tunnel undergoes the performance testing for validation and calibration. For the Ahmed Body flow pattern testing, the flow behaves just like the flow pattern tested in calibrated wind tunnel. For the case study testing, a cylinder model was used and the highest flow speed is 0.4317 m/s while the slowest flow speed is 0.1401 m/s. However for the case study experiment, the result obtained is not at its best condition as there is wake flow generated around the cylinder body and further improvement is required to obtain the undoubtedly results.
Book Synopsis Design, Fabrication and Testing of Longitudinal Wind Tunnel Balances for Micro Air Vehicle Applications by : Andrew T. Walter
Download or read book Design, Fabrication and Testing of Longitudinal Wind Tunnel Balances for Micro Air Vehicle Applications written by Andrew T. Walter and published by . This book was released on 2004 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt: "This research presents the design, implementation and testing of two new wind tunnel balances for capturing longitudinal aerodynamic data (lift, drag, and pitching moment) from MAV scale models"--Abstract.
Book Synopsis Low-Speed Wind Tunnel Testing by : Jewel B. Barlow
Download or read book Low-Speed Wind Tunnel Testing written by Jewel B. Barlow and published by Wiley-Interscience. This book was released on 1999-02-22 with total page 736 pages. Available in PDF, EPUB and Kindle. Book excerpt: Low speed wind tunnels are used to test vehicles which travel at a rate of under 300mph, such as automobiles, and propellor aircraft. This book covers aspects of the technology from the design and use of wind tunnels to the instrumentation used.
Book Synopsis The design, analysis, and testing of a wind tunnel model with active aerodynamic controls for flutter suppression by : Randall Murray Bolding
Download or read book The design, analysis, and testing of a wind tunnel model with active aerodynamic controls for flutter suppression written by Randall Murray Bolding and published by . This book was released on 1978 with total page 526 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis The Design, Fabrication, and Testing of a Wind Tunnel for the Study of the Turbulent Transport of Aerosols by : Malcolm Swope Child
Download or read book The Design, Fabrication, and Testing of a Wind Tunnel for the Study of the Turbulent Transport of Aerosols written by Malcolm Swope Child and published by . This book was released on 1992 with total page 112 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Author :National Aeronautics and Space Administration (NASA) Publisher :Createspace Independent Publishing Platform ISBN 13 :9781722242046 Total Pages :60 pages Book Rating :4.2/5 (42 download)
Book Synopsis Application of Rapid Prototyping Methods to High-Speed Wind Tunnel Testing by : National Aeronautics and Space Administration (NASA)
Download or read book Application of Rapid Prototyping Methods to High-Speed Wind Tunnel Testing written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-07-08 with total page 60 pages. Available in PDF, EPUB and Kindle. Book excerpt: This study was undertaken in MSFC's 14-Inch Trisonic Wind Tunnel to determine if rapid prototyping methods could be used in the design and manufacturing of high speed wind tunnel models in direct testing applications, and if these methods would reduce model design/fabrication time and cost while providing models of high enough fidelity to provide adequate aerodynamic data, and of sufficient strength to survive the test environment. Rapid prototyping methods utilized to construct wind tunnel models in a wing-body-tail configuration were: fused deposition method using both ABS plastic and PEEK as building materials, stereolithography using the photopolymer SL-5170, selective laser sintering using glass reinforced nylon, and laminated object manufacturing using plastic reinforced with glass and 'paper'. This study revealed good agreement between the SLA model, the metal model with an FDM-ABS nose, an SLA nose, and the metal model for most operating conditions, while the FDM-ABS data diverged at higher loading conditions. Data from the initial SLS model showed poor agreement due to problems in post-processing, resulting in a different configuration. A second SLS model was tested and showed relatively good agreement. It can be concluded that rapid prototyping models show promise in preliminary aerodynamic development studies at subsonic, transonic, and supersonic speeds. Springer, A. M. Marshall Space Flight Center...
Book Synopsis Scientific and Technical Aerospace Reports by :
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1994 with total page 836 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis The Design, Fabrication, and Evaluation of a Low-speed, Low-turbulence, Anechoic Wind Tunnel by : Brian J. Kaplan
Download or read book The Design, Fabrication, and Evaluation of a Low-speed, Low-turbulence, Anechoic Wind Tunnel written by Brian J. Kaplan and published by . This book was released on 1996 with total page 188 pages. Available in PDF, EPUB and Kindle. Book excerpt: "In order to provide a means for testing noise reduction techniques in propellers and fans, a low-speed, low-turbulence, anechoic wind tunnel was designed, fabricated and evaluated at Embry-Riddle Aeronautical University."--Leaf iv.
Book Synopsis Design Basis for a New Transonic Wind Tunnel by : John Burnett Willis
Download or read book Design Basis for a New Transonic Wind Tunnel written by John Burnett Willis and published by . This book was released on 1982 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: The existing ARL Transonic Wind Tunnel, which is the largest such tunnel in Australia, has severely limited testing capabilities due to a low test Reynolds number and an inadequate test section size. These deficiencies are becoming more acute as military aircraft performance capabilities increase. For current fighter aircraft, the ratio of tunnel test to flight Reynolds number is about 1:100 and the extrapolation of tunnel data to flight carries a high risk of serious error and for some conditions is not possible at all. The small test section size limits the scale of the models which can be tested. The difficulty of machining small models to the required accuracy produces excessive manufacturing times. Moreover, it is not possible to incorporate remotely adjusted control surfaces. These two factors severely restrict tunnel productivity. Various new types of transonic wind tunnels have been suggested overseas and these are discussed briefly. Configurations suitable for local needs are considered, and the basic specification for an appropriate wind tunnel is provided.
Book Synopsis Wind Tunnel Model Design and Test Using Rapid Prototype Materials and Processes by : Richard R. Heisier
Download or read book Wind Tunnel Model Design and Test Using Rapid Prototype Materials and Processes written by Richard R. Heisier and published by . This book was released on 2001 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt: Whether an airframe is a new design, modification of an existing design, or evaluation of a competing or foreign design, an accurate, high-confidence representation of the airframe aerodynamics is paramount to any low-risk design or evaluation effort. These aerodynamic estimates are used for vehicle and component sizing, performance estimates, and autopilot design and evaluation. The advent of new rapid prototyping manufacturing techniques and materials could provide a means to reduce the cost associated with the acquisition of a wind tunnel model (WTM), provided the data obtained with the rapid prototype model (RPM) were of sufficient fidelity to justify its use. The Johns Hopkins University Applied Physics Laboratory (JHU/APL) has developed a WTM design that consists of a steel strongback with rapid prototype plastic components attached to it to provide the overall vehicle configuration. In a test at the Lockheed Martin Missile and Fire Control%Dallas High-Speed Wind Tunnel (HSWT), this model (designated RPM-01) demonstrated acceptable data quality and test-to-test data repeatability with a geometrically similar steel and aluminum model. RPM-01 was built for approximately a quarter of the cost and a fraction of the time required of the all-metal high-fidelity model.
Book Synopsis Design, Construction and Characterization of a Wind Tunnel by : Chang Ge
Download or read book Design, Construction and Characterization of a Wind Tunnel written by Chang Ge and published by . This book was released on 2015 with total page 47 pages. Available in PDF, EPUB and Kindle. Book excerpt: The wind tunnel is the most fundamental test equipment for aircraft testing and studying aerodynamics. Because of the complexity of the test-subject's geometry, it is difficult to study the aerodynamic pattern simply based on theoretical calculations. Most of the aerodynamics experiments still use wind tunnels. The progress of the wind tunnel is highly related to the advancements in air crafts. Aircraft manufacturing has pushed the wind tunnel technology forward. Wind tunnels can be categorized by the wind speed limit differences, which are controlled by the mechanism of the driving methods, structure applications, etc. In this case, we built a small scale wood based wind tunnel for future testing of "Magnetic Augmented Rotational System (MARS)". This thesis discusses the low speed wind tunnel, subsonic wind tunnel, transonic wind tunnel, supersonic wind tunnel, hypersonic wind tunnel, high enthalpy hypersonic wind tunnel, and puts the focus on low speed wind tunnel. The characteristics of the low speed wind tunnel and the related data will be presented along with its advantages and shortcomings.
Book Synopsis Wind Tunnel Design for Testing V/STOL Aircraft in Transition Flight by : Richard A. Kroeger
Download or read book Wind Tunnel Design for Testing V/STOL Aircraft in Transition Flight written by Richard A. Kroeger and published by . This book was released on 1972 with total page 103 pages. Available in PDF, EPUB and Kindle. Book excerpt: Wind tunnels have afforded the best potential for studying regions of aerodynamic uniqueness of V/STOL aircraft, but they have been of limited value because of the magnitude of the flow interference they introduce. A new wind tunnel concept is described for covering the spectrum of transition testing from hover throughout wing sustained flight. The wall interference corrections are physically produced by the structure of the wall. A small scale tunnel was designed, constructed, and tested employing this concept. Data from a small rotor model were obtained in the new tunnel and a large conventional one as a basis for comparative evaluation. (Author).
Book Synopsis International Aerospace Abstracts by :
Download or read book International Aerospace Abstracts written by and published by . This book was released on 1999 with total page 1042 pages. Available in PDF, EPUB and Kindle. Book excerpt:
