has a free simple calculator here that you may use. It is important for you to calculate the Reynolds Number so that you can produce an accurate chart for your model. In this plot, the lift coefcient and drag coefcient are. Figure 1.1 is a plot of his results for the N60 airfoil across a range of Re. His studies showed that the thick cambered airfoil has a critical Re where the perfor-mance changes drastically. Then we can use this to plot the lift coefficient of the airfoil. shapes: a thin at plate, a thin cambered plate, and a thick cambered airfoil (the N60). This will result in a Reynolds Number of 1,069,722. In aviation, a Reynolds Number is calculated using an airfoil’s chord width, the speed at which the airfoil is moving through the air measured in meters per second, and the Kinematic Viscosity of the fluid the airfoil is traveling through. It is used to predict the lift characteristics of an airfoil.įor example: I have a wing root chord of 0.646583 meters, that is traveling through 20 degree air at 25 meters per second. Each line is calculated based on a Reynolds number. I have plotted 2 lines on the chart for two. The example chart in this article is the lift coefficient of a supercritical airfoil. Who really does that these days anyway besides aeronautical students? Knowing how airfoils behave will give you, as a designer, greater flexibility in your wing design.Ĭl v Lift charts are computer generated or can be manually calculated using an equation. Now, with CAD software like Solidworks, Fusion 360 and other 3D design tools, we can design and build planes with far more predictable and intended results. Using well known and simple airfoil templates were the way to go. Historically, scratch builders of model airplanes did not rely on sophisticated software when creating their wings. Rest assured it is very simple to read and understand and will help you decide on airfoils for your future flying model airplanes. At first glance it may be a little bit intimidating. In this article we will take a more lay person's look at how to read a Polar Plot chart of Lift Coefficient.
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