Calculation of Wing Flutter by a Coupled Fluid-Structure Method

Abstract

An integrated computational uid dynamics (CFD) and computational structural dynamics (CSD) method is developed for the simulation and prediction of utter. The CFD solver is based on an unsteady, parallel, multiblock, multigrid nite volume algorithm for the Euler/Navier-Stokes equations. The CSD solver is based on the time integration of modal dynamic equations extracted from full nite element analysis. A general multiblock deformation grid method is used to generate dynamically moving grids for the unsteady ow solver. The solutions of the oweld and the structural dynamics are coupled strongly in time by a fully implicit method. The coupled CFD-CSD method simulates the aeroelastic system directly on the time domain to determine the stability of the aeroelastic system. The unsteady solver with the moving grid algorithm is also used to calculate the harmonic and/or indicial responses of an aeroelastic system, in an uncoupled manner, without solving the structural equations. Flutter boundary is then determined by solving the utter equation on the frequency domain with the indicial responses as input. Computations are performed for a two-dimensional wing aeroelastic model and the three-dimensional AGARD 445.6 wing. Flutter boundary predictions by both the coupled CFD-CSD method and the indicial method are presented and compared with experimental data for the AGARD 445.6 wing.

Flutter-driven triboelectrification for harvesting wind energy

“…Meanwhile, there has been considerable research on the basic dynamics of flexible structures like flags, which can be bent, folded, twisted or waved in the air [19][20][21][22][23][24][25][26] . The first experimental study on fluttering behaviour was performed by Taneda 27 with a flag made of various fabrics and shapes, to find a variety of flapping modes (for example, nodeless, one-node, imperfect-node and two-node flutters).…”

Assessment of the Fluid-Structure Interaction Capabilities for Aeronautical Applications of the Open-Source Solver Su2.

“…The results are illustrated in Fig. 15 that shows a comparison of the computed flutter speed indices with those found in other references [62][63][64][65]. The best approximation curve (spline) is a representation of the limit between stable and unstable regions.…”

Two Better Loosely Coupled Solution Algorithms of CFD Based Aeroelastic Simulation

“…(8) shows that two-time aerodynamic solution is needed for the implicit scheme at each physical time-step. For the corrector step of Eq.…”

“…Since the computational cost of the method is very high, exploration for better computational efficiency and quality is now a hot topic that attracts much research efforts. An implicit monolithic algorithm to solve the fluidstructure interaction problems has been documented in literature (Alonso and Jameson, 1994; Liu et al, 2001; Sadeghi and Liu, 2001). The coupling operation is carried out in every finite cell of the flow field.…”