Energy Finite Element Analysis System

New Naval initiatives, like the DD(X) program, impose stringent noise and vibration targets, and require assessment and reduction of noise due to machinery, flow, and propulsion. A typical surface ship structure exhibits thousands of normal modes below 30Hz. Thus, the frequency range of interest from signature and hull vibration objectives extends far beyond what existing finite element based methods can predict. High noise levels in living quarters and in working spaces due to acoustic emissions from machinery and operating aircraft creates habitability concerns which must also be addressed in new surface ship designs. Recently, an Energy Finite Element Analysis (EFEA) and an Energy Boundary Element Analysis (EBEA) formulation have been developed by the PI of the proposed project, and they have been applied for computing the vibration of submersible vehicles and the associated radiated noise at frequencies beyond the limits of conventional finite element methods. In addition to the Naval applications the EFEA and EBEA methods have been applied successfully in predicting vibration and acoustic fields in aerospace and automotive applications. The proposed project will lead to the development of an EFEA and EBEA system for the analysis of full scale surface ships and submarines in a robust and user friendly manner.