Download or read book Active Structural Acoustic Control of Interior Noise on a Raytheon 1900d written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-05-29 with total page 80 pages. Available in PDF, EPUB and Kindle. Book excerpt: An active structural acoustic control system has been demonstrated on a Raytheon Aircraft Company 1900D turboprop airliner. Both single frequency and multi-frequency control of the blade passage frequency and its harmonics was accomplished. The control algorithm was a variant of the popular filtered-x LMS implemented in the principal component domain. The control system consisted of 21 inertial actuators and 32 microphones. The actuators were mounted to the aircraft's ring frames. The microphones were distributed uniformly throughout the interior at head height, both seated and standing. Actuator locations were selected using a combinatorial search optimization algorithm. The control system achieved a 14 dB noise reduction of the blade passage frequency during single frequency tests. Multi-frequency control of the first 1st, 2nd and 3rd harmonics resulted in 10.2 dB, 3.3 dB and 1.6 dB noise reductions respectively. These results fall short of the predictions which were produced by the optimization algorithm (13.5 dB, 8.6 dB and 6.3 dB). The optimization was based on actuator transfer functions taken on the ground and it is postulated that cabin pressurization at flight altitude was a factor in this discrepancy.Palumbo, Dan and Cabell, Ran and Sullivan, Brenda and Cline, JohnLangley Research CenterACTIVE CONTROL; NOISE (SOUND); STRUCTURAL STABILITY; NOISE REDUCTION; OPTIMIZATION; COMBINATORIAL ANALYSIS; TRANSPORT AIRCRAFT; ALGORITHMS; FLIGHT ALTITUDE; TRANSFER FUNCTIONS; HARMONICS
Download or read book Active Structural Acoustic Control of Interior Noise on a Raytheon 1900D written by and published by . This book was released on 2000 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Active Structural Acoustic Control of Noise Transmission Through Double Panel Systems written by James P. Carneal and published by . This book was released on 1993 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Structural Acoustic Prediction and Interior Noise Control Technology written by and published by DIANE Publishing. This book was released on 2001 with total page 70 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Variational Analysis and Aerospace Engineering written by Giuseppe Buttazzo and published by Springer Science & Business Media. This book was released on 2009-08-21 with total page 527 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Variational Analysis and Aerospace Engineering conference held in Erice, Italy in September 2007 at International School of Mathematics, Guido Stampacchia provided a platform for aerospace engineers and mathematicians to discuss the problems requiring an extensive application of mathematics. This work contains papers presented at the workshop.
Download or read book Smart Structures and Materials written by and published by . This book was released on 2001 with total page 550 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Structural Acoustic Prediction and Interior Noise Control Technology Nasa written by United States. National Aeronautics and Space Administration and published by . This book was released on 2002* with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Langley Research Highlights 1999 Advanced Aerospace Technology Clouds That Help Create the Ozone Hole Capturing Comet Dust written by and published by . This book was released on 2000 with total page 70 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Active Structural Acoustic Control of Broad Band Sound Transmission Through a Panel written by D. K. Peterson and published by . This book was released on 1996 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Experimental and Numerical Analysis of Structural Acousticcontrol Interior Noise Reduction written by National Aeronautics and Space Adm Nasa and published by Independently Published. This book was released on 2018-09-19 with total page 54 pages. Available in PDF, EPUB and Kindle. Book excerpt: The research results contained in this technical report were performed under the NASA grant entitled "Experimental and Numerical Structural Acoustic Control for Interior Noise Reduction." The report is based essentially on partial progress of the Ph.D. dissertation prepared by Jeffrey S. Bevan under direct guidance of Dr. Chuh Mei. The document presents a finite element formulation and control of sound radiated from cylindrical panels embedded with piezoceramic actuators. The extended MIN6 shallow shell element is fully electrical-structural coupled. A piezoelectric modal actuator participation (PMAP) is defined which indicates the actuator performance to each of the offending modes. Genetic algorithm is also employed to validate the sensor and actuator locations determined by the PMAP criteria. The work was conducted at the Department of Aerospace Engineering, Old Dominion University. Mr. Travis L. Turner, Structural Acoustics Branch, NASA Langley Research Center is the technical monitor.Mei, Chuh and Bevan, Jeffrey S.Langley Research CenterNUMERICAL ANALYSIS; EXPERIMENTATION; NOISE REDUCTION; ACOUSTICS; ACTUATORS; RESEARCH; FINITE ELEMENT METHOD; SHALLOW SHELLS; POSITION (LOCATION); PIEZOELECTRICITY; PIEZOELECTRIC CERAMICS; PANELS; NUMERICAL CONTROL; NOISE (SOUND); CYLINDRICAL BODIES
Download or read book The Future of Air Power in the Aftermath of the Gulf War written by Robert L. Pfaltzgraff and published by DIANE Publishing. This book was released on 1992 with total page 387 pages. Available in PDF, EPUB and Kindle. Book excerpt: This collection of essays reflects the proceedings of a 1991 conference on "The United States Air Force: Aerospace Challenges and Missions in the 1990s," sponsored by the USAF and Tufts University. The 20 contributors comment on the pivotal role of airpower in the war with Iraq and address issues and choices facing the USAF, such as the factors that are reshaping strategies and missions, the future role and structure of airpower as an element of US power projection, and the aerospace industry's views on what the Air Force of the future will set as its acquisition priorities and strategies. The authors agree that aerospace forces will be an essential and formidable tool in US security policies into the next century. The contributors include academics, high-level military leaders, government officials, journalists, and top executives from aerospace and defense contractors.
Download or read book The Turbine Pilot s Flight Manual written by Gregory N. Brown and published by Wiley-Blackwell. This book was released on 2001-10-25 with total page 276 pages. Available in PDF, EPUB and Kindle. Book excerpt: Highly illustrated and clearly written, The Turbine Pilot's Flight Manual is a must have for all pilots. It offers a complete description of turbine aircraft engines and systems including turboprops and jets. Additional chapters on high-speed aerodynamics, multipilot crew co-ordination, wake turbulence and high altitude weather are discussed at length. The book is perfect for not only those involved in pure jet operations; but for those involved in turboprop, multipilot operations, and transition training. It is a key tool for a successful turbine aviation career.
Download or read book Economic Security Neglected Dimension of National Security written by National Defense University (U S ) and published by Government Printing Office. This book was released on 2011-12-27 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt: On August 24-25, 2010, the National Defense University held a conference titled “Economic Security: Neglected Dimension of National Security?” to explore the economic element of national power. This special collection of selected papers from the conference represents the view of several keynote speakers and participants in six panel discussions. It explores the complexity surrounding this subject and examines the major elements that, interacting as a system, define the economic component of national security.
Download or read book Jane s All the World s Aircraft written by and published by . This book was released on 2001 with total page 928 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Engineering Noise Control written by David A. Bies and published by CRC Press. This book was released on 2017-12-01 with total page 826 pages. Available in PDF, EPUB and Kindle. Book excerpt: This classic and authoritative student textbook contains information that is not over simplified and can be used to solve the real world problems encountered by noise and vibration consultants as well as the more straightforward ones handled by engineers and occupational hygienists in industry. The book covers the fundamentals of acoustics, theoretical concepts and practical application of current noise control technology. It aims to be as comprehensive as possible while still covering important concepts in sufficient detail to engender a deep understanding of the foundations upon which noise control technology is built. Topics which are extensively developed or overhauled from the fourth edition include sound propagation outdoors, amplitude modulation, hearing protection, frequency analysis, muffling devices (including 4-pole analysis and self noise), sound transmission through partitions, finite element analysis, statistical energy analysis and transportation noise. For those who are already well versed in the art and science of noise control, the book will provide an extremely useful reference. A wide range of example problems that are linked to noise control practice are available on www.causalsystems.com for free download.
Download or read book The Social Construction of Technological Systems written by Wiebe E. Bijker and published by MIT Press. This book was released on 1989 with total page 428 pages. Available in PDF, EPUB and Kindle. Book excerpt: "The impact of technology on society is clear and unmistakeable. The influence of society on technology is more subtle. The 13 essays in this book have been written by a diverse group of scholars united by a common interest in creating a new field - the sociology of technology. They draw on a wide array of case studies - from cooking stoves to missile systems, from 15th-century Portugal to today's Al labs - to outline an original research program based on a synthesis of ideas from the social studies of science and the history of technology. Together they affirm the need for a study of technology that gives equal weight to technical, social, economic, and political questions"--Back cover.
Download or read book On the Frontier written by Richard P. Hallion and published by . This book was released on 1984 with total page 420 pages. Available in PDF, EPUB and Kindle. Book excerpt:
