Experimental identification of K-space characteristics

This paper addresses energy propagation features in ribbed panels over a wide frequency range. An evaluating tool for wave propagation characteristics in one- or two-dimensional structures is first introduced. For bi-dimensional domains, a new method based on inhomogeneous wave coorelation is implemented, using sparse measured or extracted data. The sparse measurements are here the normal velocity patterns of a ribbed panel set. This leads to theta-dependent wavenumbers. New insights regarding the behavior of the stiffened plates used into the k-space are enhanced : the structural orthotropy has a significant influence on the low-frequency response. These last elements are in good agreement with results obtained with homogenized models. Moreover, a new high-frequency typical behavior is experimentally highlighted. This effect is directly linked to the waveguide nature of the stiffeners.