DRAG COEFFICIENT WITH ASPECT RATIO CALCULATOR SKIN

Surface roughness eliminates the run of the laminar boundary layer over the front part of the airfoil and makes it turbulent, increasing skin friction drag. (f) The minimum drag coefficient with roughness. (e) The lift-to-drag ratio at an angle of attack of 8 degrees. Such characteristics are typical for certain airfoil sections, especially those used on sailplanes. There is a “bucket” in the drag curve because this airfoil experiences extended regions of laminar boundary layer flow between certain (low) angles of attack. Explain why the drag of the airfoil increases with the application of roughness. Also, why is there a “bucket” in the drag curve? (e) Center of pressure location, as shown on the plot below.Įxamine the attached graph, which shows the aerodynamic coefficients for a NACA 66 -212 airfoil section.įor the flap-up case then, estimate the following values for a Reynolds number of (you may also want to annotate the graph): (d) The best lift-to-drag ratio =, which is about 115 in this case and not untypical for a two-dimensional airfoil. (c) Drag polar (as a plot), as per the plot shown below (b) Zero-lift angle of attack = -2.75 degrees, as shown on the same plot. The slope is obtained using a least-squares linear fit. (a) Lift curve slope = 0.0949 per degree, as shown on plot below.

First, determine the values of the following parameters: (a) Lift curve slope (b) Zero-lift angle of attack (c) Drag polar (as a plot) (d) The best lift-to-drag ratio (e) Center of pressure location (as a plot). As shown in the table below, the lift, drag, and pitching moment coefficient measurements for a NACA 2412 airfoil will be used to calculate specific derived aerodynamic quantities.

Drag coefficient with aspect ratio calculator