Implicit large-eddy simulations of a three-dimensional plunging wing

Ankang Gao (Imperial College London)

The flow past a sinuously plunging wing at Reynolds number 10,000 is simulated using the incompressible Navier-Stokes solver of Nektar++. The wing has a NACA 0012 cross-section, an effective aspect ratio of 10 and an angle of attack of 15 degrees. The plunging motion has a reduced frequency from 1 to 3 and a peak-to-peak amplitude of 0.1 and 0.5. A DG-mimic spectral vanishing viscosity is used as the subgrid-scale model. High-resolution flow fields are obtained which indicates the highly turbulent nature of the flow. The fine iLES results are also filtered in a finite difference gird in the post-processing stage to highlight the strongest vortices and therefore enable a direct comparison with PIV results from experimental measurements. Good agreements are found between the numerical and experimental results. The performance of the code and the global linear system solver is also discussed.