Translation of the Physical Description of Multi-layer Train Panels into SEA Parameters: Assessment of Software and Methods

摘要

Since noise requirements are becoming stricter, it is critically important to improve vibro-acoustical characteristics of the new designs of trains, cars and aircrafts. In this sense, the SEA method allows the engineers to predict vibro-acoustical behaviour in early stages of design, only requiring a few geometrical and physical characteristics. The description of an actual structural design using a set of SEA elements is the first step in SEA modelling, crucial for a correct prediction. Many criteria, well studied and published in previous works, can be established. Conversely, the second and most difficult step is to convert the physical description (geometrical and physical properties) of each element into SEA (vibro-acoustical) parameters: modal density, internal loss factor and coupling loss factor. In recent times a lot of bibliography concerning SEA method and SEA parameters calculation has been published and a large variety of modal density and coupling loss factor calculation methods have been developed. Furthermore, available commercial SEA software has implemented internal methods for SEA parameter calculation from geometrical and physical description provided by the user. This research aims to establish a procedure for modelling multi-layer configuration panels contrasting results from different commercial software and from test results of several mock-up configurations. Medium and high frequency results from simulation were successfully validated with experimental measurements. Since multi-layer panel configurations are commonly used in railway, automotive and aeronautical applications, the conclusions of this work can be useful in a wide scope of products.