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Old 06-25-2009, 06:33 PM   #11 (permalink)
aerohead
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yah-yah

Quote:
Originally Posted by tasdrouille View Post
Phil, I would be inclined to think that you are half right on this one as the optimal diffuser's angle is dependant on the diffuser's lenght. Hucho's book showed 2 diffusers of different lenghts. For the longer one the optimal angle was around 2.5 degrees, while for the shorter one it was closer to 3.5 degrees.

Fabrio posted an image from Hucho's work on this here
tasdrouille,sorry,I'm brain dead and very late getting back as I just looked at the images.I never paid much attention to the short diffuser,as I've never done one,and somehow,what I remember from Hucho's summary was that the 2.5-degree angle was preferred for low drag.So you're more correct and it is conditional,based on long/short form. I'll take the heat for anyone who labored to fab the "wrong" diffuser.Good eye! If I get to be a liability here at EcoModder,you all can just park me out on an ice flow where I won't be able to hurt anyone.

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