Why don't wings have dimples?

"cavelamb" wrote

Having considered all the ramifications of this over the last few days,
I'm
releived that I never took up the "sport"...

I never took it up because...

The days my dad came home from work after playing golf, he was always ****ed
off. (for you Brits, that does not mean drunk g)

Why take up a form of recreation, whose primary result is to make you more
uptight? Not me!
--
Jim in NC

"Peter Dohm" wrote

I thought that I would be able to find a web site with the wind tunnel
video
that I'm sure I've seen of this; however, for this evening at least, I
must
admit that I have indeed struck out.

This is a subject that I would really like to understand; although I would
settle for a couple of good practical rules of thumb. If I happen to find
anything, I'll be sure to post it--or a link as appropriate.

I'll try one time to help you understand.

Think of your observation from aboard the golf ball. Ignore the fact that
the ball is spinning, as you are taking your observations.

The ball is moving through the air. If there is no spin, the airspeed across
the mass of the ball is the same on the top or the bottom; that is a given.

Now spin the ball as it is moving, with the bottom of the ball going towards
the destination of the ball. Now think of the airspeed 2 millimeters off the
surface of the ball, and what the airspeed is, at that point. Is the air
moving slower on the bottom? Sure it is, because the rough surface (the
dimples) of the ball is rubbing on the air, and slowing the air's movement,
as compared to the mass of the ball; faster than if the ball was smooth.
What is the air doing on the top surface? Two millimeters above the
surface, the air is being accelerated, as the roughness of the ball tries to
grab the air an throw it past the ball.

The ball does not care if it is spinning. Don't measure the speed of the
air as compared to the spinning surface, but compare it to the mass of the
ball moving through the air, OK? So review what we have said. The air is
being slowed on the bottom, and speeded up across the top. That will cause
lower pressure on the top than the bottom, which will cause lift. That will
keep the ball in the air longer, and fly further, which is what golfers
want.

I hope that helped. :-)
--
Jim in NC