Advanced Multidisciplinary Tool for Dynamic Loads Analysis of Aerospace Vehicles

Modern aerospace vehicles operate at high angles of attack and perform aggressive maneuvers, which lead to flow separation, turbulence, high dynamic loads problems such as buffet and flutter. Accurate CFD model-based simulation of these problems requires careful attention to fluid-grid movement, fluid-structure interfacing and turbulence. CFDRC proposes to develop and validate a novel structural-based "brick analogy" for dynamic grid movement and remeshing for unsteady computational aeroelasticity. In the proposed brick analogy, the structural Navier equation is applied both to structures deformation and to deforming portion of the CFD mesh, and all are solved by FEM. To preserve the grid smoothness and orthogonality, the nonlinear, large deformation with small strain rate theory is proposed. The proposed geometrically nonlinear "brick analogy" can sustain shear deformation due to the fact that the equilibrium is set up for a solid element instead of truss. In Phase I, the proposed brick analogy methodology will be developed, validated and assessed for CFD grid movement, and conservative-consistent fluid-structure interfacing will be adapted for data transfer between fluids and structures. In Phase II, the technique will be extended to couple the proposed technology with general purpose FEM structural codes and CFD codes and development of advanced unsteady turbulence modeling to analyze aerospace vehicle dynamics.