Aerodynamic Noise Generation, Suppression and Control - CANCELLED
March 15, 2010 — March 19, 2010
Coordinator:
- Efim Kudashev (Moscow University, Russia)
Aeroacoustics is one of the most challenging domains of Fluid Dynamics. A very accurate knowledge of the mechanisms of aerodynamic noise generation is required to satisfy current regulatory requirements in fields as varied as transport (airplanes and road vehicles) and safety (noise in the working environment, vibration induced mechanical fatigue). The aim of this lecture series is to present a state-of-the-art review of on-going activities in noise prediction and to indicate current research directions in a way that is accessible to attendees coming from both academic and industrial areas. Introductory lectures on the fundamentals of aeroacoustics will be followed by up-to-date reviews on theoretical developments, experimental techniques and numerical modeling in other topics of aeroacoustics from noise generation to noise propagation and noise control. The principal components determining the noise of a modern passenger aircraft as a whole are fan and turbine noise, jet noise and airframe noise. All the above choices of aerodynamic noise turn out to be important at different flight stages and, consequently, each of them must be reduced. On the other hand, to develop numerical methods of noise prediction and methods of noise control it is necessary to know noise radiation mechanisms. The proposed course will have a short introduction into the topic, emphasising the foundations of nonlinear acoustics and aeroacoustics. The introductory lectures will deal with the physical bases of aerodynamic noise from the viewpoint of nonlinear wave physics. They would also cover nonlinear phenomena occurring at the boundary and in the volume of media.
One series of lectures will be dedicated to problems of high-power noise generation in the atmosphere; interaction of high-intense modulated acoustic waves; shocks formation and the broadening of spectrum towards the high-frequency region; evolution of aerodynamic noise spectrum. Another part of the course will deal with modern theoretical approaches used for nonlinear acoustic wave propagation. The lectures are focused on basic problems of nonlinear acoustic wave propagation. An overview will be given for the propagation of nonlinear diffusive acoustic waves; behaviour of short pulses and periodic waves far from the sound source; noise from traffic, fans, motors and the design of noise barriers. Another part of the course will deal with the supersonic passenger transport and sonic boom impact. Acoustic engineering applications will concern the capabilities of different approaches, allowing an evaluation of their performance and an assessment of their suitability in various fields of research. The main objective of this course, in fact, is to allow an information transfer from well-known scientists and leaders in the aeroacoustics field, to industries and laboratories.
The course is addressed to doctoral students, young researchers as well as practicing R&D engineers, dealing with aeroacoustics and the problems of aerodynamic noise suppression.
Keywords: Acoustics, Turbulence, Flow Measurements and Visualization, Boundary Layers