Best Practices for Spacecraft Acoustic Analysis in Actran and Assesments

Acoustic loads are one of the major concern in the structural design of SpaceCrafts (SCs). They are mostly caused by the launcher fairing sound pressure level during lift-off and ascending phase. In this work a number of acoustic assessments have been performed by using MSC Actran SW and by referring to a real S/C structure and a real launch acoustic environment. Three types of acoustic analysis are available in MSC Actran for the purpose: 1)??Modal frequency analysis, 2)??Direct frequency analysis 3)??Virtual SEA analysis. Each one of these three analysis implies different assumptions and different computational effort, which may be noteworthy. Moreover, a significant number of parameters have to be carefully chosen by the analyst in order to finalize the each analysis run. The aim of this work was to make a well though engineering evaluation about which is the type of acoustic analysis most suitable for the analysis, as a good compromise between accuracy and computational costs. Moreover, some sensitivities have been run in order to identify the best parameters to be set for each type of analysis. This lead to define some best practices for the analysts in order to make more repeatable and efficient the analysis process itself.