Quote:
Originally Posted by eco_generator
So leading edge is vastly important if you are starting with a completely flat face...
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I really respect Wolf Hucho and all he is doing, so bear this in mind,when I say that unless you read every chapter of his books,you may get stuck with a 'rule' which is actually contextual and could lead to losses.
In the sections on automobiles Hucho discounts leading edge radii,essentially saying that at some degree of rounding,with further rounding you'll see no further appreciable gain in drag reduction.
In his sections on commercial vehicles,he presents drag tables which reflect the variation in Cd as a function of yaw.And it's clearly apparent that a full convex hemispherical nose has the lowest drag when in a crosswind environment.
And crosswind is so prevalent in some geographical locations that crosswind effects should be considered as significant enough to engineer for.
If you want to see some minimums,check out the U.S.Mk 46,and Mk 50 torpedo,and also the Whitehead Motofides A244 torpedo.You'll be shocked at the bluntness of their noses but these fish can really haul -ss through the water and for quite some range.
Then compare them to he Alpha I and Akula class Soviet nuclear submarines.These were the world's fastest subs up until maybe the new Virginia class.