Eventos Anais de eventos
13th Spring School on Transition and Turbulence
Comparison of different modeling strategies for the prediction of lift and drag of an UAV wing
Breno Lopes Tumelero , SC
Co-Authors: Breno Lopes Tumelero, Filipe Dutra da Silva, Rafael Cuenca
Presenter: Filipe Dutra da Silva
An accurate detection of stall on a wing is fundamental to define several parameters in aircraft design, such as lift-off speed, required runway length and maximum take-off weight. When using computational fluid dynamics tools, the correct numerical modeling is a key factor to guarantee the accuracy of the predictions of lift and drag coefficients. The present study proposes a simulation model, based on the open-source code OpenFOAM, to predict the lift and drag coefficients of wings with low-to-moderate aspect ratios at low Reynolds number. Incompressible Reynolds Averaged Navier Stokes simulations were performed for a wing with aspect ratio of 4, based on the Wortmann FX 63-137 airfoil, at a Reynolds number of 100k. Validation was performed through comparisons with experimental data and sensitivity tests to the size of the computational domain and to turbulence inflow parameters are provided. Also, grid dependency tests were conducted based on the Grid Convergence Index. In order to assess the influence of turbulence modeling on the results, two models were considered: k-ω SST and the Spalart-Allmaras. Finally, the polars are generated for each case, and the variations in the absolute values of CL and CD for each model were assessed, as well as the influence of the modeling in the detection of the wing stall. The proposed model was able to provide accurate results with relatively low computational cost, being suitable for the design of low-speed, unmanned-aircraft wings.
Unmanned aerial vehicle, Aerodynamic parameters, OpenFOAM