Welcome to the von Karman Institute for Fluid Dynamics Store

Numerical simulation of aerodynamic noise in Low Mach number flows

Be the first to review this product

Availability: In stock

€25.00
OR

Quick Overview

VKI PHDT 2007-04, Numerical simulation of aerodynamic noise in Low Mach number flows, ISBN 978-2-930389-40-0, 212 pgs

Numerical simulation of aerodynamic noise in Low Mach number flo

Double click on above image to view full picture

Zoom Out
Zoom In

More Views

  • Numerical simulation of aerodynamic noise in Low Mach number flo
  • Numerical simulation of aerodynamic noise in Low Mach number flo

Details

Numerical simulation of aerodynamic noise in Low Mach number flows
By Yves Detandt
PhD Thesis from the von Karman Institute/Université Libre de Bruxelles, Belgium, August 2007
ISBN 978-2-930389-40-0, 212 pgs
Abstract

The present work focuses on the computation of the noise generated by unsteady turbulent flows. The conversion from flow energy into acoustics has been neglected in the past due to the relative inefficiency of the transfer. Even if generally flow and sound propagate in the same medium, the acoustic and fluid research communities have been interested by completely different topics. Some fluid dynamicists however used the acoustic signature of vortex shedding to identify the frequency associated to this pure flow phenomenon and acoustic excitation has been extensively used in flow experiments to trigger or stabilize some periodic mechanisms. These are probably precursors of aeroacoustics which is a branch between acoustics and fluid dynamics analyzing the sound generated by unsteady flows.

The development of jet engines in the 1950’s triggered the interest of engineers and scientists who attempted to estimate the noise generated by different designs of
this noisy propulsion technique. Lighthill, a fluid dynamics specialist, proposed a theoretical explanation for jet noise which was subsequently extended to more complicated
flows. At this time, theory was restricted by flow analysis tools and scaling laws derived from theory were the basic tools for the design of quiet flows.

In the 1990’s, the development of efficient computers at an a ffordable cost led to a deeper analysis of flow phenomena and opened new trends for aeroacoustic methods. Economical development of civil air transport tends to increase the number of flight operations at different airports and mainly during night. People living around the airports claim for silent aircraft and the international rules for aircraft noise are more and more drastic. The last Silencer program funded by the European Union shows significant noise reduction, but also illustrates that these reductions are probably the best compromise for the actual design. New technologies have to be evaluated to meet the future imposition of noise reduction. The development of new numerical tools, which compare and point out the best designs are therefore necessary. This tendency is not limited to the civil aircraft industry. People are now used to higher and higher comfort level, and require reduction of noise generated for instance by their cars air supply system. These methods combining tools developed for flow and acoustic simulations are the central interest of this thesis and will be briefly discussed to outline the different chapters which subdivide the present work.

Additional Information

Manufacturer von Karman Institute for Fluid Dynamics

Product Tags

Use spaces to separate tags. Use single quotes (') for phrases.