Spray-on Composite System for Low Frequency Acoustic Mitigation

This Phase II proposal addresses the need for an innovative, affordable spray-on material system that mitigates low frequency acoustic radiation through a ship hull induced by airborne noise in shipboard compartments containing various electro-mechanical systems. The Phase I project objectives were fully achieved and the results exceeded the U.S. Navy project requirements. The acoustic mitigation technology developed provided, on average, an order of magnitude of additional frequency transmission loss relative to the current U.S. Navy treatment for frequencies below 200 Hz. At the same time, the proposed treatment also provided comparable high frequency transmission loss performance within the same weight limit (¡Ü 3 psf), but at one-half the thickness of the conventional treatment. The Phase II project takes technology from demonstrated feasibility through product development, qualification, and establishes the platform for application on U.S. Navy ships. This is accomplished by the development and demonstration of both prototype materials and application equipment suited for larger scale applications. The full size demonstrations will be used to prove scalability of the technology and compliance with Naval requirements related to acoustic insulation (ASTM E90) and fire safety (ASTM E84 tests). In addition, a cost benefit analysis for the proposed technology will be completed.