Modeling aeroacoustic excitations by subsonic wave packets in the Kirchhoff formalism
TypeCommunications avec actes
The present work aims at linking the shape of a wave packet to its acoustic e ciency through numerical integration of the homogeneous Helmholtz equation in the Kirchho formalism. We shall consider the case of a bidimensional, rectangular domain where one side is a ected by a spatially evolving wave packet as a boundary condition with subsonic convection velocity. In the rst place, the numerical tool is validated by comparison with analytical developments available in literature. Then, an extension to more advanced forms of wave packet is approached. The appearance of a criterion for acoustic e ciency is discussed, as well as the need for a proper de nition regarding the acoustic energy of a wave packet and its radiated energy output.
Files in this item
Showing items related by title, author, creator and subject.
SERRÉ, R.; ROBINET, Jean-Christophe; MARGNAT, F. (Acoustical Society of America, 2015)Noise generation by flows is modeled using a pressure wavepacket to excite the acoustic medium via a boundary condition of the homogeneous wave equation. The pressure wavepacket is a generic representation of the flow ...
ZAARAOUI, Abdelkader; RAVELET, Florent; MARGNAT, Florent; KHELLADI, Sofiane (Elsevier, 2013)A prototype device for measuring the volumetric flow-rate by counting vortices has been designed and realized. It consists of a square-section pipe in which are placed a two-dimensional bluff body and a strain gauge force ...
On compressibility assumptions in aeroacoustic integrals: a numerical study with subsonic mixing layers MARGNAT, Florent; GLOERFELT, Xavier (Acoustical Society of America, 2014)Two assumptions commonly made in predictions based on Lighthill’s formalism are investigated: a constant density in the quadrupole expression, and the evaluation of the source quantity from incompressible simulations. ...
CAESTECKER, Pascal; SERRE, I.; IOST, Alain; VOGT, J-B. (societe française de métallurgie et de matériaux, 2006)Lors de l’essai de Small Punch Test (SPT) (essai de micro emboutissage d’un disque d’épaisseur 0,5 mm et de diamètre 8,9 mm), le matériau est sollicité en contraintes bi-axiales, déformé plastiquement jusqu’à fissuration ...
AUGER, Thierry; VOGT, Jean-Bernard; PRORIOL SERRE, Ingrid (Elsevier, 2019)If the terminology “hydrogen embrittlement” (HE) very explicitly points to the species responsible for the physical phenomenon, it is not the same for liquid metal embrittlement (LME). Whilst the first case suggests focusing ...