Application of the Energy Based Finite Element Method for Acoustic Calculations in the High Frequency Range

The applicability of classical numerical methods, such as the Finite Element Method (FEM) or the Boundary Element Method (BEM), is often restricted to lower frequencies. A possible methodology for the investigation of higher frequency ranges can be seen in the Energy based Finite Element Method (EFEM). The EFEM is based on a summation of input, output and dissipated powers in a specific control volume. The exchange of energy between structural components is modeled by transmission coefficients. Solving the system of equations, the energy densities are obtained at each node allowing to deduce acoustic quantities like sound pressure at any point of interest. The underlying assumptions lead to a discretization which is generally independent of the considered frequency and therefore smaller compared to the FEM. In comparison to the commonly used Statistical-Energy-Analysis (SEA), the EFEM is more detailed regarding the spatial discretization of radiating surfaces and the transmission of energy between structural elements. In the current contribution the theory of the EFEM is summarized briefly and its applicability is discussed. Afterwards, the efficiency of this rather new approach is shown by means of practical examples, namely by current applications in automotive, aerospace, and marine industry.