Different grid sizes have been examined and the suitable mesh whose CL and CD are close to the experimental data had been presented. Large Eddy Simulation (LES) turbulence model is used to simulate flow at high angle of attack in near-stall or stall condition. In this paper, the effect of compressibility on stall behavior of NACA0012 airfoil at a Reynolds number of 3.98x10 6 is studied using the OpenFOAM package. For the comparison of the airfoils, the two-dimensional analysis validation of the program was done with experimental data, and the airfoils were analyzed in two dimensions under the same validated analysis conditions. Firstly, the airfoils which will be compared were selected from Eppler, Goettingen, NACA and Wortmann airfoil families. In this study, numerical investigation of nine different airfoils was performed with the aim of comparison in terms of aerodynamic performance of sailplanes by using the general public licensed computer program XFLR5. Airfoil selection of a wing design firstly requires performing aerodynamic performance analyses of different airfoils to compare according to determined requirements. One of the important design phases of an aerodynamically efficient sailplane wing is selection of the appropriate airfoil. Wing design has a critical importance for sailplanes as well as for all the aircrafts in terms of aerodynamic performance. The performance of the model turbines fabricated using the AM technique has been noticeably better than that of models produced by hand, the pre. It also allows students the capability to produce concave surfaces on the underside of their blades, which was almost impossible when producing the blades by hand methods. Utilising fused-deposition modelling (FDM) additive-manufacturing (AM) technology, students are able to produce their turbine blades by additive manufacture, which has provided an opportunity to greatly improve the accuracy and finish of the model aerofoils that students can produce, as well as ensuring geometric repeatability of blades on the same hub. Working in pairs, the students are able to make design decisions on the blade geometry and the number of blades on the turbine. This paper describes a project undertaken by most first-year Engineering undergraduates at Lancaster University in which they are set the task to design, build and test a scale-model wind turbine.
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