CFD/CSD Couping Numerical Computational Methodology

To model the nonlinear aeroelasticity of flexible high aspect ratio wings and design active aeroelastic wing(AAW),A CFD/CSD coupling numerical computational methodology is developed.In this study,an aeroelastic coupling procedure will perform with loosing coupling CFD/CSD at the same physics time step.Solving aerodynamic force employ Navier-Stokes discretized based cell-centered finite volume framework with LU-SSOR implicit time-marching second order accurate scheme and dual-time technology.Computational structural dynamics(CSD) are modeled using finite element equations.Matching the CFD grid displacements with the CSD or finite element model response maintains the accuracy in this loosely coupled approach.In the loosely coupled modular approach of two disciplines,boundary information between the CFD and CSD codes is exchanged through the developed codes' interface mappings.The CSD code calculates the response of the structure.The resulting outputs,the displacements,are interpolated to the CFD grid using a displacement mapping of conservation volume transform(CVT).The CFD code calculates the flow field about this new CFD grid.CFD/CSD coupling procedure is converged after judged by error of the deformed displacements on the CSD in the iteration.Finally,the CFD/CSD coupling computational convergence solution is obtained for a swept wing at Ma=0.8395,α=5.06°using the developed nonlinear aeroelastic methodology.History of response of the structure and aerodynamic characteristic with time is analyzed.The study show it is important that structural inertia force must consider on static aeroelastic analysis and the developed CFD/CSD coupling procedure is abler to compute nonlinear aeroelastic analysis.