PPRuNe Forums - View Single Post - Propeller tip would be stalled?
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Old 28th Jan 2015, 05:43
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Tinstaafl
 
Join Date: Dec 1998
Location: Escapee from Ultima Thule
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The prop's (for any position along the blade) AoA is vector sum of the blades rotational velocity, and the aircraft's forward speed. The blade section has a much lower speed near the hub compared to the tip due to the smaller diameter for the same RPM. Hard to show with a text a diagram so bear with me...

HUB vs TIP: Vertical lines represent rotational speed downwards, horizontal represents forwards speed. Slash is prop section. Imagine a line between the full stops to picture the resultant airflow vector.

hub at a greater AoA
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tip at a lesser AoA
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If the tip is at some reasonable +ve AoA, then the hub is at an excessive AoA
If the hub is at some reasonable +ve AoA, then the tip could even be at a -ve AoA
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