A method to investigate mid and high-frequency vibration energy transfer paths using the irrotational intensity
Résumé
Structural intensity fields provide a clear understanding of the
noise, vibration and harshness (NVH) behavior of complex structures
by showing the vibration energy flow between zones of excitation
and dissipation. The use of models with fine meshes for automotive
structures has allowed structural intensity calculations to be
performed at high frequencies. However, fields are difficult to
understand at medium and high frequencies: the intensity field has
a vortical character that hides the vibration energy flow in these
frequency ranges. In this work, a methodology is presented to
filter out vortices in the structural intensity field. The approach
uses the Hodge–Helmholtz decomposition: the structural intensity
field is decomposed into rotational, irrotational, and harmonic
components. Among them, only the irrotational component is needed
to describe the path of energy flow from sources to sinks. The
proposed methodology involves calculating the dynamic response and
solving a diffusion equation similar to the thermal conduction
equation to obtain the irrotational field of interest. Plate
examples are used to illustrate the efficiency of the method, which
provides a better understanding of the mid- and high-frequency
energy transmission paths.
Domaines
Mécanique [physics]
Origine : Fichiers produits par l'(les) auteur(s)