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Old 2nd Dec 2007, 11:49
  #128 (permalink)  
delta3
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Pressure Bubble myth

Graviman,

For publication puposes resolution is reduced, I thought still readable, but I guess this may not be the case.

Your comments on boudary conditions are right : same weight, just a different hover height.

The graph shows :

Blue : profile drag
Green : induced drag
Color : total drag

all according to the previous definitions.

Why is the induced drag so slanted, up to a negative dip on the retreating blade, this is because the rotor is already flapping given the CoG of the load, see figure: cyclic is between 2.12 and 2.25 degrees backward. This can lead to a situation that induced drag gets propulsive when the blade is flapping down. The simulator allows me to look at all data, even point per point blade elements, but then again details get so volumenous, that this would be diffult to present clearly.


d3
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