| Popis: |
Mathematical model and numerical procedure of multibody system in fluid flow is used in weakly coupled approach to simulate forward dynamics of wing with aileron model. Multibody system (MBS) is formulated as DAE index 3, and stabilised via underrelaxation. Navier-Stokes model of viscous incompressible flow is discretised with basic finite volume method on cell-centered collocated mesh arrangement. Displacement of finite volume mesh is modeled via solving elastostatic boundary value problem. The MBS generalized forces pertinent to the aerodynamic loads, after being calculated at the current deformed configuration of the aeroelastic interface, are reduced to mass center of the corresponding rigid body. The A-stable backward differencing formula is used to integrate both the fluid and MBS equations in time. In this paper, we focus ourselves on the spatial coupling, meaning that principle of virtual work (i.e. for small time steps) is adopted in the analysis. A spatial coupling algorithm applied on the aeroelastic interface is formulated as a combination of the rigid and deformable regions. Rigid regions spread on majority of each body in MBS, while deformable part of the aeroelastic interface is used to connect rigid bodies. The problem is observed in 2D, using a model of a wing with control surface in fluid flow, but the formulation is general so it is equally valid in 3D. |
