Analysis of FSI effects of blast loaded flexible structures

This paper investigates the influence of fluid–structure interaction (FSI) and aerodynamic damping on the structural response of systems subjected to blast loads. Considering FSI effects results in a different reflected pressure profile for flexible systems when compared to the classical approach in protective design neglecting any interaction effects (rigid reflection of blast pressure load). The structural properties mass and eigen frequency determine the FSI influence. The general assumption of rigid reflection is usually on the safe side but results in a significant overestimation of displacements and internal forces. Considering FSI and aerodynamic damping, the engineer can assess the structural behavior of flexible structures more accurately. The derived FSI model is valid for the analysis of weak shocks having a reflection coefficient of approximately 2. The numerical examples underline the effects of FSI and aerodynamic damping on the reflected pressure profile and on the displacements.