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The blade is 42.3 meters long and starts with a cylindrical shape at the root and then transitions to the airfoils S818, S825 and S826 for the root, body and tip, respectively. This blade also has pitch to vary as a function of radius, giving it a twist and the pitch angle at the blade tip is 4 degrees. This blade was created to be similar in size to a GE 1.5XLE turbine. For more information on the dimension characteristics of this blade, please see this M.Eng report (note that model in the present tutorial has an additional 2 meter cylindrical extension at the root to make it more realistic). The blade is made out of an orthotropic composite material, it has a varying thickness and it also has a spar inside the blade for structural rigidity. These are further described in Part 2 of the tutorial.

The wind is coming from the z-direction at 12 m/s which is a typical rated wind speed for a turbine this size. This blade is spinning incoming flow makes the blade rotate at an angular velocity of - 2.22 rad/s with respect to the incoming wind from the about the z-direction axis (the blade is thus spinning clockwise when looking at it from the front, like most real wind turbines). The upstream wind speed (or should we say the free stream velocity?) is 12 m/s which is a typical rated wind speed for a turbine this size. (say something about it being turbulent?. This  This blade therefore has a tip speed ratio, which is the ratio of tip velocity to incoming wind, of 8 (also a typical value). 

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