Abstract Summary
This work studies vibration and radiated noise from railway systems using the 2.5D Boundary Element Method (BEM) formulation in the Bézier-Bernstein space. The proposed method allows the representation of the exact geometry of the track as it is done in computer-aided design (CAD) models. Thus, it is possible to evaluate problems with complex geometries, which are usually not adequately represented by the standard BEM and Finite Element Method (FEM) formulations. Radiated noise is computed from the normal velocity at the boundary of the rail system according to the integral representation of the sound pressure. Only the track boundary is meshed, as the radiation condition is implicitly satisfied in the BEM fundamental solution. The boundary integral equations are numerically evaluated. Moreover, the methodology allows the use of arbitrary high-order elements, making it efficient for the computation of radiated noise at high frequencies. The performance of the proposed method is shown by studying the radiated noise of different track systems concerning slab track and urban rail systems. The influence of track flexibility levels on the radiated noise is evaluated. Rail, rail pad, embedded system and slab properties are considered. The computed results are compared with some published by other authors.
