An interpolation tool for aeroelastic data transfer problems

Abstract

In the loosely-coupled aeroelastic methodology, the aerodynamic and structural models are computed on different meshes. CFD tools are applied over the aerodynamic grid whereas CSM tools over the structural one. Depending on the model, the meshes can or not share an interface. In stick models, for example, there is no real interface. A common problem consists on transfering structural deformations to the aerodynamic mesh and aerodynamic loads to the structural one. In this work we have developed an interpolation tool based on Radial Basis Functions (RBF) to transfer information between loosely-coupled meshes, independent of their topologies. The problem arises when we have to deal with large meshes. In these cases, a domain decomposition is necessary to create more simplyfied fields that can be more easily handle by the interpolator. As the interpolation process is driven separately between each pair of associated blocks, the displacements at the junction nodes could be different. This fact could cause the ripping of the mesh along the junctions. A solution for this situation is also provided. The general methodology has been tested successfully in a whole aircraft configuration.