Download or read book Aero Acoustic on Automotive Exhaust Systems written by Dirk Wiemeler and published by . This book was released on 2015 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: On automotive exhaust systems aero acoustic noise is a dominant and critical noise content, which is clearly objectively and subjectively detectable. Robust test procedures are established but the simulation of this noise content has not gained ground in the real life development processes. This thesis shows that the dominating characteristic of the aero acoustic noise of automotive systems is dipole noise. The simulation of these specific noise sources with classical computational areo acoustics is very cumbersome or even just impossible. The aim of the thesis is a review of the scaling law approach for compact source models, enabling the determination of the sound power emission of discret configurations based on empirical data. Application simulations show that the use of these source models is simple and that the accuracy is acceptable within the geometry limits analysed.
Download or read book Acoustics of Ducts and Mufflers written by M. L. Munjal and published by John Wiley & Sons. This book was released on 2014-02-04 with total page 379 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fully updated second edition of the premier reference book on muffler and lined duct acoustical performance Engine exhaust noise pollutes the street environment and ventilation fan noise enters dwellings along with fresh air. People have become conscious of their working environment. Governments of most countries have responded to popular demand with mandatory restrictions on sound emitted by automotive engines, and a thorough knowledge of acoustics of ducts and mufflers is needed for the design of efficient muffler configurations. This fully updated Second Edition of Acoustics of Ducts and Mufflers deals with propagation, reflection and dissipation/absorption of sound along ducts/pipes/tubes, area discontinuities, perforated elements and absorptive linings that constitute the present-day mufflers and silencers designed to control noise of exhaust and intake systems of automotive engines, diesel-generator sets, compressors and HVAC systems. It includes equations, figures, tables, references, and solved examples and unsolved exercises with answers, so it can be used as a text book as well as a reference book. It also offers a complete presentation and analysis of the major topics in sound suppression and noise control for the analysis and design of acoustical mufflers, air conditioning and ventilation duct work. Both the fundamentals and the latest technology are discussed, with an emphasis on applications. Deals with reactive mufflers, dissipative silencers, the frequency-domain approach, and the time-domain approach. Fully updated second edition of the premier reference book on muffler and lined duct acoustical performance, in one complete volume Presents original new research on topics including baffle silencers and louvers, 3D analytical techniques, and flow-acoustic analysis of multiply-connected perforated-element mufflers Includes a general design procedure to help muffler designers in the automotive industry, exhaust noise being a major component of automobile and traffic noise pollution Written by an expert with four decades’ experience in teaching to graduate students, publishing extensively in reputed international journals, and consulting with industry for noise control as well as designing for quietness
Download or read book Acoustics of Ducts and Mufflers With Application to Exhaust and Ventilation System Design written by M. L. Munjal and published by John Wiley & Sons. This book was released on 1987-05-08 with total page 360 pages. Available in PDF, EPUB and Kindle. Book excerpt: An analysis of the major topics in sound suppression and noise control for the analysis and design of acoustical mufflers, air conditioning and ventilation duct work. Both fundamentals and the latest technology are discussed, with an emphasis on applications.
Download or read book Aeroacustic and Vibroacoustic Advancement in Aerospace and Automotive Systems written by Roberto Citarella and published by MDPI. This book was released on 2018-06-26 with total page 181 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is a printed edition of the Special Issue "Advances in Vibroacoustics and Aeroacustics of Aerospace and Automotive Systems" that was published in Applied Sciences
Download or read book Aero and Vibroacoustics of Automotive Turbochargers written by Hung Nguyen-Schäfer and published by Springer Science & Business Media. This book was released on 2013-01-06 with total page 145 pages. Available in PDF, EPUB and Kindle. Book excerpt: Aero and Vibroacoustics of Automotive Turbochargers is a topic involving aspects from the working fields of thermodynamics of turbomachinery, aerodynamics, rotordynamics, and noise propagation computation. In this broadly interdisciplinary subject, thermodynamics of turbomachinery is used to design the turbocharger and to determine its operating conditions. Aerodynamics is needed to study the compressor flow dynamics and flow instabilities of rotating stall and surge, which can produce growling and whining-type noises. Rotordynamics is necessary to study rotor unbalance and self-excited oil-whirl instabilities, which lead to whistling and constant tone-type noises in rotating floating oil-film type bearings. For the special case of turbochargers using ball bearings, some high-order harmonic and wear noises also manifest in the rotor operating range. Lastly, noise propagation computation, based on Lighthill’s analogy, is required to investigate airborne noises produced by turbochargers in passenger vehicles. The content of this book is intended for advanced undergraduates, graduates in mechanical engineering, research scientists and practicing engineers who want to better understand the interactions between these working fields and the resulting impact on the interesting topic of Aero and Vibroacoustics of Automotive Turbochargers.
Download or read book Fundamentals of Noise and Vibration Analysis for Engineers written by M. P. Norton and published by Cambridge University Press. This book was released on 2003-10-16 with total page 644 pages. Available in PDF, EPUB and Kindle. Book excerpt: Noise and Vibration affects all kinds of engineering structures, and is fast becoming an integral part of engineering courses at universities and colleges around the world. In this second edition, Michael Norton's classic text has been extensively updated to take into account recent developments in the field. Much of the new material has been provided by Denis Karczub, who joins Michael as second author for this edition. This book treats both noise and vibration in a single volume, with particular emphasis on wave-mode duality and interactions between sound waves and solid structures. There are numerous case studies, test cases, and examples for students to work through. The book is primarily intended as a textbook for senior level undergraduate and graduate courses, but is also a valuable reference for researchers and professionals looking to gain an overview of the field.
Download or read book Aeroacoustic Noise Prediction of Automotive HVAC Systems written by Matthias Tautz and published by . This book was released on 2019-07-15 with total page 228 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Automotive NVH Technology written by Anton Fuchs and published by Springer. This book was released on 2015-10-31 with total page 130 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents seven chapters examining selected noise, vibration and harshness (NVH) topics that are highly relevant for automotive vehicle development. These include applications following the major trends toward increased passenger comfort, vehicle electrification and lightweight design. The authors of the seven chapters, all of which are experts from the automotive industry and academia, present the foremost challenges and potential solutions in this demanding field. Among others, applications for sound optimization in downsized engines, noise optimization in electric powertrains, weight reduction options for exhaust systems, porous materials description, and the vibro-acoustic analysis of geared systems are discussed.
Download or read book Aeroacustic and Vibroacoustic Advancement in Aerospace and Automotive Systems written by Roberto Citarella and published by . This book was released on 2020-09-23 with total page 194 pages. Available in PDF, EPUB and Kindle. Book excerpt: This Special Issue highlights the latest enhancements in the abatement of noise and vibrations in aerospace and automotive systems. The reduction of acoustic emissions and the improvement of interior cabin comfort desired by all major transportation industries, as these areas have a direct impact on customer satisfaction and, consequently, the commercial success of new products. Topics covered in this Special Issue deal with computational approaches, instrumentation and data analysis related to noise and vibrations of fixed-wing aircraft, satellites, spacecraft, automobiles, and trains, covering aerodynamically generated noise, engine noise, sound absorption, cabin acoustic treatments, duct acoustics, and vibroacoustic properties of materials. This Special Issue also focuses on industrial aspects. Existing procedures and algorithms that are useful in reaching the abovementioned objectives in the most efficient way are illustrated in the collected papers.
Download or read book Acoustic Analysis and Design of Short Elliptical End Chamber Mufflers written by Akhilesh Mimani and published by Springer. This book was released on 2021-02-19 with total page 153 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents a three-dimensional analysis of acoustic wave propagation in an elliptical waveguide, and applies the equations and concepts to design axially short elliptical end-chamber muffler configurations which are an important component of a complex multi-pass muffler used in a modern-day automotive exhaust system. A general solution of the Helmholtz equation in elliptical cylindrical co-ordinates is presented in terms of the Mathieu and modified Mathieu modal functions. This is followed by the tabulation and analysis, for the first time, of the non-dimensional resonance frequencies of the transverse modes of a rigid-wall elliptical waveguide for a complete range of aspect ratio. The modal shape patterns of the first few circumferential, radial and cross-modes are examined with particular attention to the pressure nodal ellipses and hyperbolae. An analytical formulation is then outlined for characterizing a single-inlet and single-outlet elliptical muffler with the inlet located on the end face and the outlet located either on the end face or side-surface. The ensuing chapter is devoted toward analyzing the Transmission Loss (TL) performance of different short end-chamber mufflers, namely (a) the straight-flow configuration having ports located on the opposite face, (b) the flow-reversal configuration with ports located on the same end face and (c) configuration with inlet port on the end face and outlet on the side surface. Design guidelines are formulated in terms of the optimal location of inlet and outlet ports which suppresses the deteriorating influence of certain higher-order modes, thereby delivering a broadband TL performance. Directions for future work are discussed toward the end. In summary, this book is a one-stop solution for a practicing automotive engineer designing mufflers, for an applied mathematician studying wave propagation in elliptical geometries, and also as a niche area within noise control engineering.
Download or read book Acoustic Modelling and Testing of Advanced Exhaust System Components for Automotive Engines written by Sabry Allam and published by . This book was released on 2004 with total page 37 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Performance Exhaust Systems written by Mike Mavrigian and published by CarTech Inc. This book was released on 2014-08-15 with total page 146 pages. Available in PDF, EPUB and Kindle. Book excerpt: To extract maximum performance, an engine needs an efficient, well-designed, and properly tuned exhaust system. In fact, the exhaust system's design, components, and materials have a large impact on the overall performance of the engine. Engine builders and car owners need to carefully consider the exhaust layout, select the parts, and fabricate the exhaust system that delivers the best performance for car and particular application. Master engine builder and award-winning writer Mike Mavrigian explains exhaust system principles, function, and components in clear and concise language. He then details how to design, fabricate, and fit exhaust systems to classic street cars as well as for special and racing applications. Air/exhaust-gas flow dynamics and exhaust system design are explained. Cam duration and overlap are also analyzed to determine how an engine breathes in air/fuel, as the exhaust must efficiently manage this burned mixture. Pipe bending is a science as well as art and you’re shown how to effectively crush and mandrel bend exhaust pipe to fit your header/manifold and chassis combination. Header tube diameter and length is taken into account, as well as the most efficient catalytic converters and resonators for achieving your performance goals. In addition, Mavrigian covers the special exhaust system requirements for supercharged and turbocharged systems. When building a high-performance engine, you need a high-performance exhaust system that’s tuned and fitted to that engine so you can realize maximum performance. This comprehensive book is your guide to achieving ultimate exhaust system performance. It shows you how to fabricate a system for custom applications and to fit the correct prefabricated system to your car. No other book on the market is solely dedicated to fabricating and fitting an exhaust system in high-performance applications.
Download or read book An Aeroacoustic Study of Industrial Gas Turbine Intake and Exhaust Systems written by and published by . This book was released on 2008 with total page 115 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Method to Predict Automobile Aeroacoustic Near and Far Field Noise written by Douglas William Dietz and published by . This book was released on 2000 with total page 170 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Aeroacoustic Measurements written by Thomas J. Mueller and published by Springer Science & Business Media. This book was released on 2013-11-27 with total page 327 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book describes recent developments in aeroacoustic measurements in wind tunnels and the interpretation of the resulting data. The reader will find the latest measurement techniques described along with examples of the results.
Download or read book Methods for Predicting the Influence of Intense Sound Steady Flow and Elevated Temperature on the Acoustic Performance of Automotive Exhaust System Components written by Richard Chuka Oboka and published by . This book was released on 1973 with total page 226 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Combustion Noise written by Anna Schwarz and published by Springer Science & Business Media. This book was released on 2009-06-17 with total page 304 pages. Available in PDF, EPUB and Kindle. Book excerpt: November, 2008 Anna Schwarz, Johannes Janicka In the last thirty years noise emission has developed into a topic of increasing importance to society and economy. In ?elds such as air, road and rail traf?c, the control of noise emissions and development of associated noise-reduction techno- gies is a central requirement for social acceptance and economical competitiveness. The noise emission of combustion systems is a major part of the task of noise - duction. The following aspects motivate research: • Modern combustion chambers in technical combustion systems with low pol- tion exhausts are 5 - 8 dB louder compared to their predecessors. In the ope- tional state the noise pressure levels achieved can even be 10-15 dB louder. • High capacity torches in the chemical industry are usually placed at ground level because of the reasons of noise emissions instead of being placed at a height suitable for safety and security. • For airplanes the combustion emissions become a more and more important topic. The combustion instability and noise issues are one major obstacle for the introduction of green technologies as lean fuel combustion and premixed burners in aero-engines. The direct and indirect contribution of combustion noise to the overall core noise is still under discussion. However, it is clear that the core noise besides the fan tone will become an important noise source in future aero-engine designs. To further reduce the jet noise, geared ultra high bypass ratio fans are driven by only a few highly loaded turbine stages.
