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12th August 2008 | 16:32

#14 (permalink)

RVDT

Joined: Nov 2006

Posts: 1,951

Likes: 90

From: After all, what’s more important than proving to someone on the internet that they’re wrong? - Manson

crab,

Personally I think it is the other way around, as this is a rotorheads forum I made some assumptions of peoples prior knowledge, but I digress. Induced flow is actually only a tiny proportion of why the rotor is less efficient below "translational lift". Think of where in the disk the conditions for this could occur. Most of it is turning too slow and the most efficient part i.e the tips is engaged in a massive battle with tip vortices of their own and the garbage from the previous blade. All these theories assume ideal conditions and were conjured up many years ago. To say that the increase in lift is all due to the reduction in "induced flow" is not correct.

a) is the correct answer. (as in all exams more than likely it is the "least wrong) Increasing the mass flow as you no longer have the mass that is trying to go through more than once!

Nick Lappos sez:

Last edited by RVDT; 12th August 2008 at 17:22. Reason: To protect the innocent..................

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