Vibroacoustic response of complex equipment loaded panels

Aerospace system structures are by necessity stiffness to weight optimized, which often results in efficient coupling to their intense external acoustic environments. For many aerospace, as well as other vehicle structures, a lightweight primary or master structure is loaded with equipment or substructures. The effects of these attachments on the master structure's structural- Acoustic coupling (radiation and response) are critical for assessing the system's acoustically induced responses. However, these attachment effects are often poorly understood and also are difficult to deterministically model and predict. In this work the radiation coupling and efficiency of a class of lightweight aerospace panel (aluminum sandwich honeycomb core panel) with and without complex (electronic equipment) attachments are investigated using Power Injection (PI) experimental techniques. The panel's radiation efficiencies are explored and trended for various mechanical boundary conditions, acoustical boundary conditions, and complex equipment loading configurations. The results for the unloaded panels correlate well with theory for the edges free vs. supported and acoustically baffled vs. un-baffled. A range of complex attachment configurations, for attachment to panel mass ratios up to seven- To-one, are also evaluated and general predictive design assessment procedures developed for use by designers and noise / vibration control engineers. Copyright