High Frequency Elastic Analysis Tool

Basic mathematical models for plate and shell vibrations with fluid loading have been well established. Complications arise, however, when practical considerations such as acoustic coatings and structural stiffeners are considered. Understanding of the physics of acoustic scattering and radiation from coated, rib-stiffened, and fluid-loaded structures is important as it provides the knowledge of the self-noise modeling of hull arrays and of the acoustic target strength of submersibles. Existing structural and acoustic simulation methods are oftentimes restricted to the flexural wave component of the radiating field, not taking into account all of the physical dynamic wave propagation mechanisms, as well as to low frequencies, not being able to consider a mid-high frequency range rich in physical phenomena. Development of a new deterministic analytical model, which incorporates higher order elastic terms, allows modeling of undersea vehicles and embedded sonar systems at high frequencies, while at the same time fully accounting for the dynamic wave propagation mechanisms and interactions with the structure. This effort will provide a universal, innovative, and computationally efficient tool for three-dimensional analytical modeling of a fluid-loaded acoustic coating affixed to a rib-stiffened backing plate, capable of representing high frequency acoustic environments not suitable for conventional finite element approaches.