Polynomial filters for camera-based structural intensity analysis on curved plates

Structural intensity can be used as a measure to detect energy sources, sinks, and transfer paths in solid structures. It provides a valuable design tool for vibro-acoustic problems next to modal analysis. However, it has been proven very challenging to determine structural intensity experimentally for the general case of curved plates. This is due to the requirement of an accurate measurement of the full 3D vibrational field and the computation of spatial gradients thereof. The purpose of this paper is to propose a mesh-free, inherently smoothing, polynomial filtering approach and investigate its application for structural intensity analysis on curved plates based on a stereo camera measurement. Numerical studies are conducted to determine reasonable algorithm parameters (discretization, fitting radius, and the number of iterations) and their performance for different levels of uncertainty and various displacement fields. The results show that, depending on the uncertainty in the measurement, optimal values of the algorithm parameters exist. Furthermore, it is essential to achieve a high signal-to-noise ratio in the camera measurement. The computation of structural intensity is validated experimentally on the case of a flat plate and a curved plate (mockup oil pan). For the flat plate, good agreement with a reference finite element simulation is obtained. While it is not possible to derive quantitative results for the mockup oil pan under realistic measurement uncertainty, qualitative conclusions can be still drawn.

Jaar van publicatie:2023

Toegankelijkheid:Open