Low Cost Expendable Impulsive Sound Source

High-energy impulsive underwater acoustic sources are useful for oil and gas exploration, seabed characterization, and underwater target detection (e.g., submarine hunting). Explosive charges, such as SUS (Signal, Underwater Sound), are popular as they are readily deployable from surface or airborne platforms. SUS is routinely used to conduct transmission loss experiments used to determine bottom loss parameters, a critical parameter for understanding and predicting acoustic propagation. However, as an explosive, SUS requires special and burdensome shipping, storage, and handling. Fortunately, recent experiments have shown that implosive sound sources create impulses with similar characteristics to SUS. As an implosive source does not contain explosive or combustible material, it represents a promising, easier to use and lower cost alternative to SUS. Creare, working with our STTR collaborators at the Woods Hole Oceanographic Institution (WHOI), will develop the “Splash Bang”, a low-cost, easy-to-deploy, expendable, implosive, impulsive sound source that is completely free of explosive or combustible materials. The Splash Bang design expands on the Rupture Induced Underwater Sound Source (RIUSS) concept to improve manufacturability, lower cost, and simplify deployment. Our innovative approach includes the ability to set the implosion depth and an internal chamber design that balances potential energy, hydrodynamic flow, and acoustic considerations. The Splash Bang will be available in standard size packages (i.e., A-size sonobuoy and SUS), allowing it to be readily adopted into existing deployment infrastructure. In Phase I, we will investigate the key unexplored trade spaces associated with implosive impulse sound sources using computational fluid dynamics (CFD) modeling. In the Phase I Option period, we will evaluate our models against an experimental demonstration. In Phase II, we will use the modeling tools developed in Phase I to develop a detailed design of full-scale Splash Bangs, fabricate prototypes, and evaluate performance at sea.