A computational and experimental investigation into the aeroacoustics of low speed flows
Author : Graham Ben Ashcroft
Publisher :
Page : 216 pages
File Size : 29,6 MB
Release : 2003
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ISBN :
Author : Graham Ben Ashcroft
Publisher :
Page : 216 pages
File Size : 29,6 MB
Release : 2003
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ISBN :
Author : Stewart Glegg
Publisher : Elsevier
Page : 724 pages
File Size : 19,46 MB
Release : 2023-09-26
Category : Technology & Engineering
ISBN : 0443218587
Aeroacoustics of Low Mach Number Flows: Fundamentals, Analysis and Measurement, Second Edition provides a detailed introduction to sound radiation from subsonic flow over moving surfaces. This phenomenon is the most widespread cause of flow noise in engineering systems, including fan noise, rotor noise, wind turbine noise, boundary layer noise, airframe noise and aircraft noise. This fully updated new edition includes additional problems, illustrations and summary materials to support readers. New content covers Rapid Distortion theory (RDT), boundary layer wall pressure fluctuations, and flow induced sound at surfaces. Themes addressing non-compressible flows have also been added, offering coverage of hydroacoustic as well as aeroacoustic applications. New support materials for this edition include course outlines, problem sets, sample MATLAB codes and experimental data to be found at www.aeroacoustics.net. - Addresses, in detail, sound from rotating blades, ducted fans, airframes, boundary layers, and more - Presents theory in such a way that it can be used in computational methods and calculating sound levels - Includes coverage of different experimental approaches to this subject
Author :
Publisher :
Page : 273 pages
File Size : 20,26 MB
Release : 1995
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ISBN :
The research presented in this report has been directed to study the effects of mass injection into the flow upstream of a cavity to understand the weapon bay cavity's flow field and its aeroacoustics. The objective also was to control the development of upstream boundary layer, and therefore, to control the development of the shear layer over the cavity. Control of the shear layer has enabled us to significantly reduce or to fully eliminate the weapons bay's aeroacoustic interactions. This study was performed in a wind tunnel at several nominal Mach numbers between 0.5 to 1.8 and at unit Reynolds numbers up. (AN).
Author :
Publisher :
Page : 71 pages
File Size : 33,95 MB
Release : 1995
Category :
ISBN :
The research presented in this report has been directed to study the effects of mass injection into the flow upstream of a cavity to understand the weapon bay cavity's flow field and its aeroacoustics. The objective also was to control the development of upstream boundary layer, and therefore, to control the development of the shear layer over the cavity. Control of the shear layer has enabled us to significantly reduce or to fully eliminate the weapons bay's aeroacoustic interactions. This study was performed in a wind tunnel at several nominal Mach numbers between 0.5 to 1.8 and at unit Reynolds numbers up to 17 millions per foot. Measurements were performed for a number of injection distributions. The large amplitude oscillations measured without mass injection was successfully and totally eliminated with proper mass injection.
Author : Jay C. Hardin
Publisher : Springer Science & Business Media
Page : 525 pages
File Size : 15,85 MB
Release : 2012-12-06
Category : Science
ISBN : 1461383420
Computational aeroacoustics is rapidly emerging as an essential element in the study of aerodynamic sound. As with all emerging technologies, it is paramount that we assess the various opportuni ties and establish achievable goals for this new technology. Essential to this process is the identification and prioritization of fundamental aeroacoustics problems which are amenable to direct numerical siIn ulation. Questions, ranging from the role numerical methods play in the classical theoretical approaches to aeroacoustics, to the correct specification of well-posed numerical problems, need to be answered. These issues provided the impetus for the Workshop on Computa tional Aeroacoustics sponsored by ICASE and the Acoustics Division of NASA LaRC on April 6-9, 1992. The participants of the Work shop were leading aeroacousticians, computational fluid dynamicists and applied mathematicians. The Workshop started with the open ing remarks by M. Y. Hussaini and the welcome address by Kristin Hessenius who introduced the keynote speaker, Sir James Lighthill. The keynote address set the stage for the Workshop. It was both an authoritative and up-to-date discussion of the state-of-the-art in aeroacoustics. The presentations at the Workshop were divided into five sessions - i) Classical Theoretical Approaches (William Zorumski, Chairman), ii) Mathematical Aspects of Acoustics (Rodolfo Rosales, Chairman), iii) Validation Methodology (Allan Pierce, Chairman), iv) Direct Numerical Simulation (Michael Myers, Chairman), and v) Unsteady Compressible Flow Computa tional Methods (Douglas Dwoyer, Chairman).
Author :
Publisher :
Page : 216 pages
File Size : 43,33 MB
Release : 1986
Category : Astronautics
ISBN :
Author : Karen I-Yen Pao
Publisher :
Page : 156 pages
File Size : 47,48 MB
Release : 1993
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Author :
Publisher :
Page : 456 pages
File Size : 45,74 MB
Release : 1995
Category : Aeronautics
ISBN :
Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.
Author : Pradera-Mallabiabarrena Ainara
Publisher : LAP Lambert Academic Publishing
Page : 208 pages
File Size : 23,54 MB
Release : 2015-08-10
Category :
ISBN : 9783659768378
This work studies a flexible methodology to predict radiated noise. The main contributions of this work are focused on the way flow parameters are acquired in fluid dynamics simulations are synthesised, stored and later used to predict radiated noise, but also on the procedure considered in the radiation calculations. The methodology has been restricted to low Mach number flows where the noise generation is dominated by the interaction of the flow with a surface at least one of whose typical dimensions is short compared to the wavelength of intereset, known as a compact source. The radiation calculations may employ purely analytical methods or numerical methods, depending on the application. Finally, the requirements in data storage and transfer are significantly reduced by using this method. Besides, if the flow remains essentially the same, the Computational Fluid Dynamics simulation should not need to be repeated in case different acoustic scenarios should be studied.
Author : Zhongliang Jing
Publisher : Springer Nature
Page : 597 pages
File Size : 39,14 MB
Release : 2021-06-01
Category : Technology & Engineering
ISBN : 9813360607
This book presents high-quality contributions in the subject area of Aerospace System Science and Engineering, including topics such as: Trans-space vehicle systems design and integration, Air vehicle systems, Space vehicle systems, Near-space vehicle systems, Opto-electronic system, Aerospace robotics and unmanned system, Aerospace robotics and unmanned system, Communication, navigation, and surveillance, Dynamics and control, Intelligent sensing and information fusion, Aerodynamics and aircraft design, Aerospace propulsion, Avionics system, Air traffic management, Earth observation, Deep space exploration, and Bionic micro-aircraft/spacecraft. The book collects selected papers presented at the 4th International Conference on Aerospace System Science and Engineering (ICASSE 2020), organized by Shanghai Jiao Tong University, China, held on 14–16 July 2020 as virtual event due to COVID-19. It provides a forum for experts in aeronautics and astronautics to share new ideas and findings. ICASSE conferences have been organized annually since 2017 and hosted in Shanghai, Moscow, and Toronto in turn, where the three regional editors of the journal Aerospace Systems are located.