Investigating, Simulating and Applying Geometric Scaling Effects in the Prediction and Calculation of Aerodynamic Coefficients from Wind Tunnel to Real Scale

Studying the effects of the model scale on wind tunnel tests of aerodynamic vehicles and their components to generalize it to the real scale is a very important because of the direct impact on the performance of the flight system. The aim of the present research is to present a methodology for applying geometric scaling effects of NACA 0012 airfoil the on airfoil aerodynamic performance. AnsysFluent2019R3 software has been used to simulate and investigate the effects of geometric scale on the airfoil aerodynamic performance. Sixteen scale scenarios include changing the Reynolds and the angles of attack assuming Mach constant is 0.256. The airfoil chord length of 50cm (Reynolds 3 million) is considered as the base model in the simulations. The rate of deviation of the validated results for the drag and lift coefficients are 11 and 1 percent, respectively. The results showed that at angle of attack of 10 doubling the airfoil length leads to a decrease of 7.92% in the drag, an increase of 1.25% in the lift and decrease of 18.30% in the pitch moment coefficients. Halving the length of the airfoil at an angle of attack of 15 leads to an increase of 16.29, a decrease of 3.49 and an increase of 9.22% of drag, lift and pitch moment coefficients. One of the important achievements of the present study is the presentation of a methodology for applying the geometric scaling effects in the form of correlations for aerodynamic performance parameters of drag, lift and pitch moment coefficients.