Vibroacoustic and shock response prediction of a low altitude earth observation satellite using statistical energy analysis and virtual mode synthesis and simulation

Abstract

Typically, the most severe high frequency dynamic environments encountered by spacecrafts are high intensity acoustic field generated during launch and shock induced by the activation of pyrotechnic devices during launch vehicle separation. Analysis of spacecrafts’ response to these high frequency loads is important for optimal design and to guarantee performance of flight hardware, electronic equipments, etc that are vulnerable to failure under such loads. Unfortunately, the conventional deterministic methods (finite and boundary element method) become inefficient and less useful as analysis frequency increases due to the intrinsic feature of wave dynamics and unavoidable uncertainties concerning dynamic properties of complex structures. Alternative probabilistic method called the statistical energy analysis (SEA) has proven itself as a reliable tool for high frequency vibroacoustic analysis. Although SEA is limited to steady-state response analysis, virtual mode synthesis and simulation (VMSS) can be adapted with SEA for high frequency transient response analysis. In this study, vibroacoustic analysis of a low altitude earth observation satellite under high intensity acoustic field is performed using SEA with experimentally determined SEA parameters. VMSS is then applied in conjunction with SEA for launch vehicle separation shock analysis of the satellite. The prediction results show good agreement with the experimental results over the frequency range of interest.