École Nationale Supérieure de
Techniques Avancées

Abstract

In some electrical plants, acoustic disturbances appear and can reach important levels of noise. They could even damage infrastructures. These disturbances are due to a coupling between flow and acoustic. In order to avoid damages, it is important to create tools which can show and predict such coupling. Large Eddy Simulations in Computational Fluid Dynamic give precise results but these results are hard to understand. Thus different modal methods will be tested in this internship in order to have a more precise understanding of this coupling. First we use the POD method which came from the field of reduced order modelling. Then we study so called “global” modes by using Arnoldi method on a large eigenvalue problem. “Global” modes are linked to the phy- sical problem so they really show coupling phenomena but they are harder to get unlike POD modes which are less “physical”.