On the mechanism of noise generation by turbulence
Abstract
A mechanism of sound production described by Lighthill (1954) is considered. It is pointed out that the obtained equation cannot be evaluated unless more information is available about the turbulent flow field or the fluctuating stresses. Flow models have been devised to facilitate the solution of the given equation, which can be written in an approximate form involving a volume integral. Attention is given to randomly distributed compact radiators, the line antenna model, and a quasi-ordered compact source model. A model which can describe the lower order statistical behavior of the turbulent flow is considered. It is suggested that a mutual interaction of some quasi-ordered coherent structures might play an important role in the development of flow and the generation of noise.
- Publication:
-
In honor of Carlo Ferrari
- Pub Date:
- 1974
- Bibcode:
- 1974hcft.conf..449L
- Keywords:
-
- Aerodynamic Noise;
- Noise Generators;
- Subsonic Flow;
- Turbulence Effects;
- Acoustic Measurement;
- Flow Distribution;
- Lighthill Method;
- Mathematical Models;
- Shear Layers;
- Turbulent Flow;
- Two Dimensional Jets;
- Fluid Mechanics and Heat Transfer