Reduced Order Aerodynamic Model for Aeroelastic Analysis of Complex Configurations in Incompressible Flow

Abstract

D ETERMINATION of the aeroelastic behavior of subsonic flying vehicles is of great importance. This is partly due to lighter airframe requirements for most applications. Consequently, aeroelastic analyses are becoming regular routines in airframe design processes. Aeroelastic responses can be predicted using aeroelastic codes based on Euler or Navier–Stokes solvers coupled with structural dynamics solvers. However, the major drawback of the aforementioned technique, even for simple three-dimensional geometries, is the required computational time and memory to run the full aeroelastic simulation. In practice, however, simple and accurate methods are needed to predict aeroelastic responses accurately. The modal analysis technique for structural dynamics analysis is quite routine and widely used for constructing reduced-order models (ROMs). It should be mentioned that this technique was recently applied for unsteady flow analysis, as well. The reduced-order structure andfluidmodels were employed to construct reduced-order aeroelastic models [1–5] that are mostly applicable to simple geometries such as 2-D airfoils and flat wings in the discrete-time domain. The objective of this work is to develop a general reduced-order aeroelastic model for 3-D complex geometries in subsonic incompressible flow regimes in the continuous-time domain. In this regard, a boundary element method (BEM) based fluid eigenanalysis solver [6] is integrated with a finite element method (FEM) based modal technique of structural modeling. II. Structural Modeling