In situ characterisation of exemplary rail vehicle structure borne sound sources

Abstract

A narrowband characterisation of structure borne sound sources is needed for an accurate prediction of rail vehicle interior noise. Typical rail vehicle sources are relatively large and heavy structures. In 2019, a measurement method for the indirect determination of the blocked force was standardised. It can be applied in situ, with the source connected to an arbitrary receiving structure and was found to be promising for rail vehicle applications in recent research projects. One major challenge is the need to measure the coupled velocity and mobility of all relevant degrees of freedom (six directions per coupling point). Within the European Shift2Rail project DESTINATE, measurements were carried out using a traction motor and an HVAC unit as exemplary sources to investigate the suitability of the in situ method for rail vehicle sources. The measurements include translational and rotational degrees of freedom. Recently, they were further analysed to investigate the effects of neglecting degrees of freedom. The results will be shown in this contribution.