A New Investigation of the Effect of Airfoils Thicknesses on the Transition Point in Laminar Flows using XFOIL

In this work, a detailed analysis has been performed to study the influence of airfoil thickness on the location of the laminar to turbulent transition point. This study has been conducted on six types of airfoils that belong to the FFA_W3_XXX series [1]. For a constant Reynolds number (Re = 3 × 106) and for different angles of attack, the aerodynamic characteristics of the analyzed airfoils (Lift and Drag coefficients, transition point, ...) have been determined using XFOIL code, then various graphs have been plotted to illustrate the obtained results. Firstly, it has been shown that for negative angles of attack, the location of the transition points on the suction surface decreased significantly when airfoils thicknesses increased and the opposite results have been observed for the positive angles. Secondly, for all values of the incoming flow angles the lift coefficient has been shown a slight increase when airfoils thicknesses go up. Whereas, the maximum lift to drag ratio has been obtained for airfoils thicknesses ranging from 27% and 33% under positive angles of attack.