Application of OTPA as a multi-dimensional tool for gaining a deep understanding of the sound transmission of rail-bound vehicles

The Operational Transfer Path Analysis (OTPA) is an experimental method which provides a toolbox to perform contribution analyses in various kinds of ways by choosing different intersection planes for the reference signals. Depending on the positions of the reference sensors a source contribution analysis, link/interface contribution analysis or panel contribution analysis can be performed. Especially the link/interface contribution analysis and the panel contribution analysis are very helpful to gain a clear understanding of the structure-born and airborne sound transmission and enable a target-oriented sound engineering. This paper describes the measurements, the captured operational conditions, the performed analyses and necessary preparations for performing reliable OTPA's at the concrete example of a new subway train. Moreover, the sound transmission will be presented and discussed in detail in order to illustrate the possibilities of that technique.