________________________________________________________________________ THE INTERNATIONAL SOUND AND VIBRATION DIGEST Volume 6, Number 1, 12 April, 2000 (c) The International Institute of Acoustics and Vibration, (IIAV) http://www.iiav.org (IIAV is affilated to the International Institute of Theoretical and Applied Mechnanics (IUTAM) http://www.iutam.org ) ________________________________________________________________________ Dear IIAV Member: We are very pleased to bring you the latest issue of the IIAV International Sound and Vibration Digest (ISVD). This particular issue of the Digest focuses on current university and institutional research. Back issues can be found on the IIAV website: http://www.iiav.org A list of the universities with web addresses is presented. This is followed by a brief description about the research for the 29 universities or institutes and companies that responded to the request for information. We sincerely thank you for your contributions. Before the research descriptions, announcements concerning the next IIAV Congress, the IIAV election, and refereed IIAV journal (IJAV) are made. We are interested to hear from readers of the Digest about their opinions of the current format and about what they would like to see in future issues. Malcolm J. Crocker Executive Director IIAV Associate Editor, ISVD Digest e-mail: mcrocker@eng.auburn.edu Jonathan Blotter Editor-in-Chief, ISVD Digest e-mail: blotterj@isu.edu _____________________________________________________________________ ITEM 1. The Seventh International Congress on Sound and Vibration, Garmisch Partenkirchen, Germany, July 4-7, 2000 Following the successful last Congress in Copenhagen, Denmark (ICSV6), July 5-8, 1999, we are all now looking forward to the next Congress (ICSV7) to be held in Garmisch Partenkirchen, Germany, July 4-7, 2000. There has been an overwhelming response to the call for papers. So far over 700 participants have pre-registered to attend the Congress and from these, 620 abstracts have been received for presentation. Full details of the previous Copenhagen Congress ICSV6 and the next Congress ICSV7 can be found on the IIAV website by going to http://www.iiav.org and then clicking "Congresses" and then either "Congress in Denmark" or "Garmisch 2000." ************************************************************************* ITEM 2. IIAV Election 2000 IIAV is about to hold its annual election for officers and directors. This year there is an election for IIAV president, for a two year term. In addition there is an election for six new directors to replace the five retiring and one director who will become the president. Directors hold four year terms. Altogether IIAV has 20 directors on its Board of Directors. These directors meet at annual Board Meetings, normally held at the annual IIAV congresses. When you receive your ballot form soon by airmail, please return it by airmail or fax as soon as possible. Full details about the responsibilities of IIAV officers and directors can be found under "Bylaws" at the IIAV website: http://www.iiav.org ******************************************************************** ITEM 3. IIAV Journal, International Journal of Acoustics and Vibration (IJAV) The International Journal of Acoustics and Vibration started publication in December 1996 and has been published four times each year since. It currently has five or six articles in each issue. If you would like to have an article considered for publication, please follow the IJAV Instructions for Authors. These can be found in each issue of IJAV, or at the IIAV website: http://www.iiav.org by clicking "Publications" and "Information for Authors." Also at this location you can find the IIAV Calendar of Events by clicking "Calendar." ************************************************************************* ITEM 4. RESEARCH SUMMARIES Summary List of Institutions (A brief overview of the research at these institutions is presented following this list) 1. RMIT University in Victoria, Australia, http://www.me.rmit.edu.au/ 2. Department of Mechanical Engineering, Saga University, Japan, http://www.saga-u.ac.jp 3. Xian Jiaotong University, China, http://diagnosis.xjtu.edu.cn or http://www.monitoring.com.cn 4. Laboratory of Acoustics, College of Engineering, University of Porto, Portugal, http://www.fe.up.pt/~carvalho/laic.htm 5. Center for Intelligent Material Systems and Structures, Department of Mechanical Engineering, Virginia Tech, USA, http://www.cimss.vt.edu 6. Decibel Sudamericana, Argentina, S.A., http://www.decibel.com.ar 7. Noise & Vibration Technology Department at Cummins Engine Company, USA, http://www.cummins.com 8. Engineering Department, Cambridge University, UK, http://www-mech.eng.cam.ac.uk/dynvib/ http://www.eng.cam.ac.uk/annual_reports/ar9798/dynamics.htm 9. Acoustics and Vibrations Research, University of Alabama, USA, http://www.aemua.org 10. Russian Academy of Sciences, Russia, http://www.akin.ru , Acoustical Physics http://www.maik.rssi.ru 11. Tisseyre & Associés, Acoustic Consultants, France http://www.planete-acoustique.com 12. Measurement and Control Engineering Research Center, Idaho State University, USA, http://www.coe.isu.edu/engrg/mcerc.html 13. University of Sheffield, UK, http://www.shef.ac.uk/uni/academic/A-C/acse/ 14. Department of Mechanical Engineering, University of Adelaide, South Australia, http://www.mecheng.adelaide.edu.au/anvc/home.shtml 15. University of California, Los Angeles, USA http://www.mae.ucla.edu 16. Department of Acoustic Technology, Technical University of Denmark, Denmark, http://www.dat.dtu.dk 17. Institut fuer Theretische Grundlagen der Fahrzeugtechnik, Germany http://www.tu-dresden.de/vkitgf/itgf.htm 18. Mechanical Engineering, University of Ljubljana, Slovenia 19. Section Engineering Dynamics, Group Structural Acoustics, University of Technology, Eindhoven, The Netherlands, http://www.wfw.wtb.tue.nl/dyna 20. Australian Defence Force Academy,Australia, http://www.adfa.edu.au/amec 21. Imperial College, NDT group, London, England, UK, http://www.me.ic.ac.uk/dynamics/ndt 22. Faculty of Natural Sciences, Mathematics and Education; University of Split, The Republic of Croatia, http://www.unist.hr 23. University of Technology, Sydney, Australia http://www.eng.uts.edu.au/~samuel 24. Auburn University, Acoustics and Vibration Research Labs, USA http://www.eng.auburn.edu/department/me/faculty/crocker/acoustic.htm 25. Indian Institute of Technology, Bombay Powai, Mumbai- 400 076, India, E-mail: dnm@me.iitb.ernet.in 26. Indian Institute of Science, Bangalore, India http://www.frita.iisc.ernet.in 27. Acoustics Research Institute of the Austrian Academy of Sciences Vienna, Austria-Europe http://www.kfs.oeaw.ac.at 28. Werner Dobrzynski, DLR, Institut für ntwurfsaerodynamik, Braunschweig, Germany 29. DLR, Institut für Entwurfsaerodynamik, Abteilung Technische Akustik, Braunschweig, Germany E-mail: syed.ahmed@dlr.de ________________________________________________________________________ Brief Information about each Institution ________________________________________________________________________ 1. RMIT University in Victoria, Australia The Department of Mechanical and Manufacturing Engineering at RMIT University in Victoria, Australia has a postgraduate team with a strong focus on aerodynamically generated noise in motor vehicles. The team, led by Associate Professor Simon Watkins, has a 3m x 2m closed test section quiet wind tunnel, which is used for full-size car testing, a small, very quiet open jet tunnel. They also utilise a larger full-size open jet aero-acoustic tunnel, based at Monash University, also in Victoria. Current research programs include: o comparison of interior cabin noise measured on-road and also in the wind tunnels; o fundamental studies of the acoustics of very small cavities (relevant to join lines in vehicles and components); o the influence of A-pillar geometry on mean and fluctuating surface pressures and; o the dynamics of passenger cars under turbulent winds. Instrumentation includes a binaural head system, an ellipsoidal directional microphone and pressure-based systems for measuring fluctuating velocities in three dimensions under harsh environments. Further details can be found at http://www.me.rmit.edu.au/ ************************************************************************** 2. Department of Mechanical Engineering, Saga University, Japan We are studying noise reducing devices for jet noise, perforated tubes, slotted tubes, and plugged nozzles. We are using sound intensity and acoustic holography techniques. The goal is to determine the noise source, the propagation mechanism and the power level at the observed point. Also, we are studying the vibration mechanism of thin materials. Our web address is http://www.saga-u.ac.jp ************************************************************************** 3. Xian Jiaotong University The Research Institute of Diagnostics & Cybernetics of Xian Jiaotong University is one of research institutes of Xian Jiaotong University. Combining basic engineering science with advanced achievements in the fields of electronics, information science, computer technology, artificial intelligence, the institute devotes to the research activity in engineering condition monitoring and fault diagnosis to develop the diagnosis technology and instruments. The Institute is gearing towards mechanical, petrochemical, power, electronic, and building material industries, communication and transportation, etc. in order to assure the operation safety of equipment and to improve the quality of productions. In the new millennium, the institute is interested in the engineering application of evolutionary computation (EC), data mining and KDD, bootstrap, wavelet transform (WT), self-organization map and Baysian network in order to utilize these achievements in engineering diagnostics. For example, rotor-balancing technique in high speed is implemented using holospectrum theory. The vibrational diagnostic features of engineering objects are found using data mining. The mobile engine sound features are also extracted and a sound database is established by continuous wavelet transform to recognize the potential internal faults. There are more than 30 full-time researchers involving one professor, three associate professors, five instructors and more than 20 doctor and master students in the institute, who devote them to the theory of engineering diagnostics and developing advanced and practical software and instruments. If you are interested with the research projects, please visit the homepage http://diagnosis.xjtu.edu.cn or http://www.monitoring.com.cn. ************************************************************************* 4. Laboratory of Acoustics, College of Engineering, University of Porto, Portugal Current research at the Laboratory of Acoustics of the College of Engineering (University of Porto, Portugal) http://www.fe.up.pt/~carvalho/laic.htm - Acoustics in Churches ( http://www.fe.up.pt/~carvalho/igrejas.htm) - Sound Absorption Coefficients of Building Materials - Acoustical Proprieties of Cork - Expeditious noise mapping at a municipal level *********************************************************************** 5. Center for Intelligent Material Systems and Structures, Department of Mechanical Engineering, Virginia Tech, USA Smart Damping Our work examines the use of piezoceramic devices, as well as viscoelastic elements in various configurations as damping treatments to suppress unwanted vibrations in structural elements such as satellite components, aircraft panels and automobile interior parts. We combine the use of piezoelectric materials with electronic shunts, piezoelectric materials with viscoelastic damping treatments is a form of hybrid damping, and active control using piezoceramic self sensing actuation. We examine various configurations for combining viscoelastic and piezoceramic damping treatments in view of the mechanics of layered media and in view of controllability considerations. The various designs and configurations studied are based on trying to take advantage of the best properties of passive damping treatments and of active damping provided by smart structures' actuation. These materials allow the construction of unobtrusive sensors and actuators fully integrated into a structural system along with any viscoelastic material. One advantage of using piezoceramic elements combined with viscoelastic elements is the possibility of using the active component to compensate for the temperature and frequency dependence of a viscoelastic element rendering a treatment that is insensitive to these effects. Solutions are compared with classic constrained layer damping treatments. Applications include aircraft, automobiles, and inflated satellite components. Our web site is http://www.cimss.vt.edu *************************************************************************** 6. Decibel Sudamericana, Argentina, S.A. Decibel Sudamericana S.A. is an Argentine private concern working in acoustic metrology, project design and solutions to control noise and vibration. We manufacture acoustic products, and represent also both local and international enterprises. The professional components of our company impart lessons in local universities as well as in Chile and Uruguay as invited professors and lecturers. We expect to close an agreement within this year with the Fraunhofer Institute of Stuttgart, and to begin a possible relationship with the Technische Universitaet, Berlin. Web page: http://www.decibel.com.ar *************************************************************************** 7. Noise & Vibration Technology Department at Cummins Engine Company The Noise & Vibration Technology department at Cummins Engine Company sponsors university research related to diesel engine noise and vibration. Examples of recent sponsored research include: 1. Indirect Measurement of Forces Exciting Engine-Like Structures, Purdue University 2. Signature Recovery Techniques with Applications to Engine Valve Trains, Purdue University 3. Prediction of Engine Rigid Body Vibration and Dynamics, University of Michigan 4. Misfiring Cylinder Diagnosis Through Crankshaft Torsional Vibration Measurement, University of Cincinnati 5. Membership in the Vibro-Acoustics Consortium, University of Kentucky We are also interested in gear train dynamics (rattle) and other topics related to engine noise generation and reduction. More information about Cummins is available on the web at http://www.cummins.com ************************************************************************** 8. Engineering Department, Cambridge University Vibrations Research Vibration transmission in buildings and the ground Railway-induced noise and vibration Base-isolation of Buildings Mechanics of musical instruments Vibration damping of composite plates Wavelet methods for the analysis of vibration and noise data http://www-mech.eng.cam.ac.uk/dynvib/ http://www.eng.cam.ac.uk/annual_reports/ar9798/dynamics.htm Acoustics Research Research topics include: Aircraft noise, tyre noise and underwater noise. Flow instabilities controlled by suitably designed feedback controllers. Gas turbine combustors and thermoacoustic oscillations http://www.eng.cam.ac.uk/annual_reports/ar9798/energy.htm#Acoustics *********************************************************************** 9. Acoustics and Vibrations Research, University of Alabama, USA The University of Alabama has a rapidly growing research program in the areas of vibrations and acoustics. Faculty (department) and their areas of specialization include Dr. W. Marvin Johnson (Music.) - Electronic Music; Dr. Teik C. Lim (Mechanical Engineering.) - Automotive NVH, Gear Dynamics, Noise Quality, Active Control; Dr. Sally A. McInerny (Aerospace Engr. And Mechanics) - Fault Detection, Rocket Noise, Vibroacoustics; Dr. Robert Scharstein (Electrical Engr.) - Scattering, Diffraction, Stochastic Wave & Media Problems; Dr. W. Steve Shepard (Mechanical Engr.) - Vibration Isolation, Damping, Active Control, Fluid-Loading; Dr. Wendy Shiau (Communicative Disorders) - Hearing and Psychoacoustics. Over $1M of research in is currently underway in these faculty areas, supporting over 8 Ph.D., 6 M.Sc., and 3 undergraduate students as well as 3 post-doctoral researchers. Those interested in graduate level research are encouraged to contact either the Department of Mechanical Engineering (www.me.ua.edu) at (205) 348-6324 or the Department of Aerospace Engineering and Mechanics (http://www.aemua.org) at (205) 348-7300. ************************************************************************ 10. Russian Academy of Sciences We inform you about web addresses of institutes of the Russian Academy of Sciences ( RAS ) where acoustic research projects are fulfilled and web address of the journal of RAS - "Acoustical Physics". N. N. Andreev Acoustics Institute http://www.akin.ru ; General Physics Institute (Center of Wave Researches) http://www.gpi.ru ; Acoustical Physics http://www.maik.rssi.ru ************************************************************************ 11. Tisseyre & Associés, Acoustic Consultants Our research subjects : 1. Prediction of the acoustic insulation between rooms, using only standard, readily available data (geometry, density, position...) 2. Low frequency behaviour of construction elements, combining Sewell's approach with the influence of eigenmodes 3. Intelligibility in reverberant rooms, comparison of the STI method with a direct measurement method 4. Reverberation and intelligibility when using multiple loudspeakers 5. Outdoor noise measurements : correlations between noise indices and the type of environment : urban, suburban, countryside, density of road traffic etc. 6. Room acoustics parameters : calculation with the Hall Acoustics computer model, development of the model 7. Directivity at a receiver in a room and its use to determine shape and position of reflectors and other essential contributors to a hall's acoustics. More information : http://www.planete-acoustique.com ******************************************************************* 12. Measurement and Control Engineering Research Center, Idaho State University, USA Most of our current research efforts are in the area laser based displacement measurement techniques. We are heavily focused on Electro-Optic Holography and Projection Moiré interferometry. The underlying goal of these methods is to develop techniques to measure and control the structural-borne noise and energy flow in vibrating structures. In conjunction with the University of Idaho, we are also working to develop a new class of passive vibration and acoustic suppression system. Vibration energies of two mechanical systems are coupled using reversible piezoelectric transducers connected by a passive circuit. The coupling is designed in such a way to use existing energy to cancel or reduce unwanted vibrations and consequent sound radiation. Two arrangements are being considered: transfer of vibration energy from one structure to another, and transfer of vibration energy from one mode to another on a single structure. The first case employs a linear connecting circuit, while the latter employs a nonlinear connecting circuit to couple the energy. The primary impact of this work is that a new approach to the control of vibrations and acoustic radiation from structures will be developed. Reductions in system weight, cost, and complexity compared to current methods can be realized. http://www.coe.isu.edu/engrg/mcerc.html ************************************************************************** 13. University of Sheffield, UK The active sound and vibration control (ASVC) research group at the University of Sheffield has been in existence for over ten years within the department of Automatic Control and Systems Engineering. The group currently comprises over 10 researchers, and is headed by Dr Osman Tokhi. Some of the research programs currently in progress include Intelligent/Adaptive active noise and vibration control. Control of vibration of flexible structures. Analysis and design of active noise control systems. Hybrid functional electrical stimulation (FES): Assistive technology for the handicapped. High-performance parallel architectures for real-time signal processing and control. Modeling and recognition of speech. Further information can be found on the web-site: http://www.shef.ac.uk/uni/academic/A-C/acse/ *************************************************************************** 14. Department of Mechanical Engineering, University of Adelaide, South Australia The Department of Mechanical Engineering at The University of Adelaide, South Australia has a significant proportion of its research effort devoted to noise control and acoustics. This area of research involves 3 full-time Academic Staff, seven full time research staff, two full time Technical Staff and eleven graduate students. Most of the research is associated with active noise and vibration control project. These projects include active control of sound transmission into enclosed spaces including launch vehicles, mobile mining equipment cabins and aircraft cabins, energy density sensing, virtual pressure and energy density sensors, active control of noise radiated by large electric power transformers, semi-active vibration absorber development, combined acoustic/vibration absorber design, and 100-channel control system development. For more information, contact either Professor Hansen (chansen@mecheng.adelaide.edu.au) or Dr Zander (azander@mecheng.adelaide.edu.au). A sample of publications and projects is available on our web site at http://www.mecheng.adelaide.edu.au/anvc/home.shtml ********************************************************************* 15. University of California, Los Angeles Here at University of California, at Los Angeles, in the Department of Mechanical and Aerospace Engineering, we have an active research program in Acoustics and related Fluid Mechanics. Professor William C. Meecham, PhD, has a group working in computational acoustics: 1. Using Large Eddy Simulation to calculate the Fluid Mechanics for a free jet, these results are employed with the Lighthill analogy to compute the Aerosound. The method has been employed for isotropic free turbulence, a free low speed jet, a jet impinging on a flat plate, a subsonic free jet and transonic free jets. 2. Extensive work is underway on active noise control for interior aircraft noise. The method uses a piezo-electric element with a damping sandwich. Professor Jon Freund, PhD has an active program in Direct Numerical Simulation of free jet noise for supersonic flow. He uses a number of latest PC's for parallel computation. He has extensive results for this exact calculation. Professor John Kim, PhD (Editor of the Physics of Fluids; HE and Prof. Moin of Stanford, were the first to calculate Direct Numerical Simulation--at Re of over 1000): Dr. Kim has a group calculating using Direct Numerical Simulation for the calculation of Fluid Mechanics in boundary layers and channel flow. These results are being used to calculate the noise generated in such flows. Our web site is http://www.mae.ucla.edu ********************************************************************** 16. Department of Acoustic Technology, Technical University of Denmark The Department of Acoustic Technology, Technical University of Denmark, has a staff of 23 employees, 18 of whom are researchers. The high level of research activity is reflected in the fact that more than 75 percent of the financial support to the Department is from external sources, including research grants from national and international foundations and contributions from industry. The researchers at the Department of Acoustic Technology have knowledge and many years of experience in general linear acoustics, electro-acoustics, architectural acoustics, vibro-acoustics, psycho acoustics, advanced measurement techniques, and noise and vibration control. The Department has been involved in a number of EU-projects over the last few years. These are: Reduction of Helicopter Interior Noise, Turbo Fan Noise Prediction and Control, and Active Control of Structural Vibration using Power Transmission Methods. The department is currently participating in three EU-projects: Basic Research on Duct Acoustics and Radiation, Statistical Energy Analysis Thematic Network, and Conservation of the Acoustical Heritage by the Revival and Identification of the Sinan's Mosques Acoustics. Other projects include Annoyance of Low Frequency Noise, Subjective Evaluation of Noise from Neighbours, and the Room Acoustic Calculation Model ODEON. There are ongoing PhD studies of Numerical Transducer Modeling, Sound Source Reconstruction using Inverse Sound Field Calculations, and New Methods for Transducer Calibration, and recent PhD studies include Active Control of Noise from Vibrating Structures, Spatial Equalisation of Sound in Rooms, and Occlusion Effects Caused by Earmoulds. A Center for Applied Hearing Research is being established. Web site: http://www.dat.dtu.dk ************************************************************************** 17. Institut fuer Theretische Grundlagen der Fahrzeugtechnik Research Topics - statistical energy analysis, especially using this method in the railway industry - vehicle acoustics - modal analysis - FE-methods, especially for noise radiation of wheels - Multi-body-systems (dynamik for railway vehicles) http://www.tu-dresden.de/vkitgf/itgf.htm Other institutes within the Technical University of Dresden with research activities in the acoustical field: - Institut fuer Akustik und Sprachkommunikation (Laboratory of Acoustics and Speech Communication) http://www.ias.et.tu-dresden.de - Institut fuer Festkoerpermechanik (Professur fuer Maschinenedynamik und Schwingungslehre) http://www.tu-dresden.de/mw/ifkm/Chairs/Hardtke/index.html *************************************************************************** 18. Mechanical Engineering, University of Ljubljana Askerceva 6, 1000 Ljubljana, SLOVENIA, E-mail: mirko.cudina@fs.uni-lj.si University research in the field of acoustics 1) Noise Generation by Rotating Stall and Surge in Axial Turbomachines. A characteristic of axial flow turbomachines is instabilities in their performance and noise in partial load operation. Those instabilities are a consequence of rotating stall and surge representing the lowest region of operating stability. This research project wants to highlights the occurrence of the rotating stall and surge generation phenomenon and its influence on the emitted noise using the fundamental turbine equation, noise spectra measurements, and their analysis. 2) Noise as an Indicator of Cavitation and Instability in Centrifugal Pumps. Instabilities of turbopumps can be caused by the onset of stall and surge, and/or by cavitation. Stall and surge occur at flow rates below the design flow rate whereas cavitation can occur within the entire range of operating conditions. Cavitation of a centrifugal pump is the result of insufficient net positive suction head and causes excessive noise. Although the cavitation process causes a turbulent noise the research results show that the beginning of cavitation process in the centrifugal pump can well be detected by a single discrete frequency. 3. Development and analysis of AE sources locator using neural networks. Research and development of intelligent locator of discrete and continuous acoustic emission sources which is based on neural networks. The intelligent locator is capable to locate acoustic emission sources on complicated technical constructions build of different metals and composite materials and has ability of self-adaptation to different geometrical structures and different materials by self-learning process. Last research is focused on location of multi-source acoustic emission, where different independent acoustic emission sources are mixed together instantaneously and convolutively. ************************************************************************** 19. Section Engineering Dynamics, Group Structural Acoustics, University of Technology, Eindhoven, The Netherlands The research in the section Structural Acoustics is concentrated on topics related to low-noise design. The emphasis in recent years and in the forthcoming period will be on computational methods for application in design tools in an engineering environment: a) By recent research the group has made significant progress in realizing fast computational tools for the vibrations and sound radiation of (nearly) axisymmetric structures. The primary application of this work is low-noise design of Magnetic Resonance Imaging systems. However, other applications, e.g. in the areas of wheel noise from trains of sound radiation of carrillon bells are of interest as well. b) An upcoming research topic is the modeling of high-frequency structural vibrations and the associated sound radiation. This refers to the frequency range in which structural wavelengths are small compared to the characteristic geometrical dimensions. Important examples for low-noise design are road vehicles, railway carriages, aircraft, ships, or MRI-scanners. In order to deal with these 'uncertain systems', a research program has been defined in co-operation with the TNO-institute of Applied Physics, titled: 'Robust design tools for low-noise products'. In this program two PhD-students are invited to apply: PROJECT 1: Analysis methods for low-noise products with uncertain parameters: - literature survey and assesment of recently proposed prediction techniques for uncertain dynamic systems. - development of a robust and efficient method for acoustic applications. PROJECT 2: Design tools for low-noise products with uncertain parameters: - development of a design tool for complex systems, e.g. an MRI-scanner. During this project numerical as well as experimental research will be performed on one or more industrial products. - formulating design rules for complex uncertain systems, for example for: worst-case analyses, optimizations, or for determining the maximal allowable product tolerances. We are looking for students with a background in one of the engineering sciences (project 1,2), or applied mathematics, or applied physics (project 1). For more information please visit the above mentioned web address. Applications preferably by e-mail. Prof.dr.ir. J.W. Verheij, verheij@tno.tpd.nl Dr.ir. G. Verbeek, bertv@wfw.wtb.tue.nl http://www.wfw.wtb.tue.nl/dyna ************************************************************************** 20. Australian Defence Force Academy Research in sound and vibration at the Australian Defence Force Academy is primarily undertaken by the Acoustics and Vibration Unit within the School of Aerospace and Mechanical Engineering. The Australian Defence Force Academy, which is a College of the University of New South Wales, is located in Canberra, Australia. Current research projects include vibro-acoustic studies of variable speed electrical drives, brake squeal noise, pressure-controlled oscillating valves as applied to biological and musical acoustics, the role of vibration and acoustic signals in foraging termites, traffic noise prediction, numerical modeling of impact machinery noise, development of acoustic and vibration measurement techniques, various issues in occupational noise and environmental noise, vibration isolation and power transmission. http://www.adfa.edu.au/amec ************************************************************************ 21. Imperial College, NDT group The current research in the Imperial College NDT group has two main goals, the first being the development of rapid inspection methods which will make it feasible to inspect structures and components which are currently either not inspected or are inspected only on a sample basis because of the time and expense involved, while the second goal is the development of techniques for the inspection of constructions such as adhesive bonded joints for which there is currently no satisfactory inspection method. Within each goal, the projects fall into two broad categories: the development of new non-destructive testing (NDT) techniques and the investigation of existing techniques whose principles are not well understood in order to put them on a sound scientific basis. Most of the work is split between ultrasonic guided wave methods and those employing bulk waves; we also have an active interest in lower frequency (sonic) vibration techniques. http://www.me.ic.ac.uk/dynamics/ndt ************************************************************************** 22. Faculty of Natural Sciences, Mathematics and Education"; University of Split, The Republic of Croatia Passive Detection of Underwater Signal, "Research in Passive Detection Theory of Extremely Weak Underwater Signals" There exist general conceptions about underwater signal detection in noise. The fundamental contribution to this subject deals with various realizations of the underwater signal detection systems. But these systems are built for detecting only narrow-band signals or for detecting only wide-band signals. This work will treat the problem of the passive underwater signal detection of the extremely weak underwater signals in the presence of the deep-sea random noise and generated by the very silent underwater vessels. The signal is supposed to be a normal stochastic process, the sum of the two essential parts statistically independent: the one due to a vessel cavitation and that owing to the operating machinery, mechanisms and propeller. The increase of the detection probability is expected for the optimal detection algorithm compared to the single detection of the narrow-band or wide-band signal conceptions and results of the research can be usefully applied to other research fields. Concretely: in medicine (cardiography, encephalography), in geology (earthquake prognosis), in military technology (passive detectors, electronic counter measures), in astronomy (distant space objects detection) and in others related research fields. University of Split - http://www.unist.hr Faculty of Natural Sciences, Mathematics and Education - www.pmfst.hr Ministry of Science and Technology of the Republic of Croatia http://www.mzt.hr ********************************************************************* 23. University of Technology, Sydney, Australia Smart Actuators for Active Flow Control Active flow control typically require large and complex infrastructure with a significant weight penalty. We have been investigating smart actuators with the curious property of zero mass-flux but non-zero momentum flux. These ctuators are formed by a cavity with an oscillating membrane in one face and an orifice in the other. The downstroke of the membrane causes fluid to be ingested by the cavity, whilst the upstroke forces fluid out of the cavity. The flow separates at the orifice lip, forming a vortex which moves away from the orifice under its own momentum. Ideally, on the downstroke this vortex is sufficiently distant from the orifice that it is not reingested by the cavity. Thus, over a single period of oscillation of the membrane, whilst there is zero net mass-flux into or out of the cavity, there is also a non-zero mean momentum flux. This momentum flux is, effectively, a jet which has been synthesized from the ambient fluid. Work at UTS has focussed on the fundamentals of synthetic jet actuators but has also considered a number of control applications such as delaying separation and enhancing mixing. Web-page http://www.eng.uts.edu.au/~samuel Main researchers: S.G. Mallinson, G.Hong and J.A Reizes ************************************************************************ 24. Auburn University Acoustics and Vibration Research Auburn University possesses a Sound and Vibration Research Laboratory in the Mechanical Engineering Department. Several faculty members, visiting scholars and graduate students conduct their research there. Since its founding, over 20 masters and doctoral students have graduated having conducted research into acoustics, noise control engineering and vibration. Sponsors have included, NASA Marshall; NASA Langley; NASA/JPL; IBM Charlotte, North Carolina; IBM Austin, Texas; American Gas Association; US Navy; National Science Foundation (NSF); Department of Defense (DOD), and others. Currently a project for the Trane Corporation, Tyler, Texas concerning Noise Reduction Studies of Residential Air-Conditioning Units is underway. The acoustical facilities, instrumentation and software at Auburn include: an anechoic room, a two-reverberation room suite for transmission loss measurements; modern FFT and real time analyzers, etc., for acoustics and vibration measurements; and FEM, BEM and statistical energy analysis (SEA) software. For further information, contact Prof. Malcolm J. Crocker, e-mail: mcrocker@eng.auburn.edu Web page: http://www.eng.auburn.edu/department/me/faculty/crocker/acoustic.htm ********************************************************************** 25. Indian Institute of Technology, Bombay Powai, Mumbai-400 076, India Project 1: Diagnostic Monitoring and analysis of Gearbox noise and vibration Sponsor: Department of Science and Technology, Government of India Project 2: Vibro-acoustic Analysis of Launch Vehicle Structures using Statistical Energy Analysis (SEA) Sponsor: Department of Space, Government of India Project 3: Statistical Energy Analysis Software for Ship Noise Prediction Sponsor: Naval Science and Technology Laboratory, DRDO, Ministry of Defense, Government of India. E-mail: dnm@me.iitb.ernet.in ********************************************************************** 26. Indian Institute of Science, Bangalore 560 012, India The Indian Institute of Science is an over-ninety-year old post-graduate research institute of international repute. It comprises over forty departments and centres in different disciplines of science and engineering, and is a deemed university. Over fifty percent of its 1650 students are research students. The stress is on academic excellence while the faculty pursues research and offers post-graduate teaching, industrial consultancy, continuing education, etc. The most cost effective way for noise control is to control it at the source, or better still, to design for quietness. Design engineers need to be taught how to design for quietness through continuing education courses. Quieter technologies need to be adopted where available and developed where necessary. Appreciating this need, Department of Science and Technology of the Government of India identified Technical Acoustics as one of the important emerging areas and decided to set up a "Facility for Research in Technical Acoustics" (FRITA) at the Indian Institute of Science, Bangalore 560 012, India, with Prof. M.L. Munjal as Convener. The primary objectives of FRITA include: a. Disseminating knowledge about quieter technologies to different sections of industry by means of short courses; b. Development of quieter technologies where necessary; c. Acting as a clearing house for all problems about noise pollution referred to it by the Central Pollution Control Board; d. Developing a course on designing for quietness for the engineering undergraduates; e. Offering consultancy services for control of noise from existing machines or industries; f. Creating public awareness about development of quieter socio-religious living habits; and g. Collaborating wwith similar centres/institutions abroad through exchange visits for development of quieter technologies. Apart from this major facility for technical acoustics, research in vibration and other aspects of acoustics is being pursued in the departments of Civil Engineering, Aerospace Engineering and Electrical Communication Engineering of the Indian Institute of Science. Similarly some research in this area is being carried out at Indian Institute of Technlogies at Delhi, Kanpur, Kharagpur, Guwahati, Chennai and Mumbai. Unfortunately very little research is being done at other universities in the country. http://www.frita.iisc.ernet.in ************************************************************************ 27. Acoustics Research Institute of the Austrian Academy of Sciences Vienna, Austria, Europe Research in Acoustics has been concentrated in the recently founded "Acoustics Research Institute" of the Austrian Academy of Sciences with emphasis on Computational Acoustics and development of new software. A short review (i) is enclosed. The institutes homepage can be accessed by http://www.kfs.oeaw.ac.at Quite uniquely, "Musical Acoustics" is the focus of research at the "Institut für Wiener Klangstil", Director: Prof. Gregor Widholm, of the Vienna University of Music and Performing Arts, with the homepage http://www.mhsw.ac.at The best equipped laboratory for noise measurement in Vienna is part of the leading engineering college, TGM-Wien. Focus of research is on industrial and traffic noise reduction. Access is through the homepage http://www.tgm.ac.at of TGM with links to the Laboratory: "Versuchsanstalt fuer Waerme- und Schalltechnik am TGM". Email: "Head: HR Mag. Mathias Stani " mathias.stani@tgm.ac.at Problems in Acoustics and in Structural Vibrations are occasionally solved by research teams of the Institutes of the Vienna University of Technology (TU-Wien), homepage http://www.tuwien.ac.at The Institute of Lightweight Structures and Aerospace Engineering (ILFB) is active in the field of fluid structure interaction vibration. It can be accessed by the homepage of the Vienna University of Technology (TU-Wien) http://www.tuwien.ac.at. *************************************************************************** 28. Werner Dobrzynski, DLR, Institut für Entwurfsaerodynamik / Braunschweig Full-scale A320 wing successfully tested for airframe noise in the DNW In a world-wide first the DLR Institute of Design Aerodynamics, Braunschweig, Germany, investigated the aeroacoustics of a full-scale Airbus A320 wing in the open test section of the DNW. This project on aircraft airframe noise sources - supported by the German Ministry of Education and Research (BMBF) and by DaimlerChrysler Aerospace Airbus - served to try and understand the dominant aeroacoustic mechanisms specifically of the wing high-lift devices - leading edge slats and trailing edge flaps (including flap side edges). Farfield noise directivities were determined for different slat/flap settings, angles-of-attack and flow speeds, respectively. A planar-array of 100 microphones and DNW's new acoustic 3-m-diam. mirror were used to localize and rank order different HLD component sources. The results showed the dominance of certain additional noise sources related to construction details, never revealed in the past on scaled aircraft models. Slat noise and flap side-edge noise were found to be the dominating airframe noise component. The research will continue to develop technically feasible noise reduction means. Further details are given in a paper: Dobrzynski, W.; B. Gehlhar; H. Buchholz: "Model and full-scale High-lift Wing Wind Tunnel Experiments dedicated to Airframe Noise Reduction", Paper at the 7th International Congress on Sound and Vibration, 4-7 July 2000, Garmisch-Partenkirchen, Germany. E-mail: werner.dobrzynski@dlr.de ********************************************************************* 29. DLR, Institut für Entwurfsaerodynamik / Abteilung Technische Akustik, Braunschweig Aerodynamic and aeroacoustic interaction between helicopter main- and tail rotors Aerodynamic and aeroacoustic interaction phenomena are a common feature of the helicopter rotor flow fields. These problems are more severe in modern helicopters due to the compact designs and increased rotor disc loadings. The need for tools to predict and analyze the interaction phenomena in the early design stages of a helicopter is apparent. An unsteady 3-D panel method code with full-span free wake, which was developed at the Institute of Design Aerodynamics, Acoustics Division of DLR Braunschweig, Germany, to simulate the aerodynamics and aeroacoustics of single multi-blade rotors in arbitrary motion, has been extended to treat the simultaneous rotation of a main- and tail-rotor. The unsteady pressure distribution obtained on the blades of the main- and tail-rotor serves as input to a Ffowcs-Williams Hawkings-equation based acoustic code to analyse the acoustics. To date a generic two-blade main- and tail-rotor configuration in hover and a BO105 four-blade main- and two-blade tail-rotor in a forward climb flight have been studied in detail. E-mail: syed.ahmed@dlr.de ************************************************************************ END OF ISVD DIGEST, 12 APRIL, 2000 (c) INTERNATIONAL INSTITUTE OF ACOUSTICS AND VIBRATION (IIAV)