G’day All,
Sometimes when I’m in a bit of pensive mood,my mind moves to deep and complex problems,such as…‘does the light stay on when you close the fridge door’…and other serious things like that…
Well last night,I was wondering about the Air Stream inside our Flutes..
After the air has left the lips and enters the Flute,does it ‘spiral’ until it reaches the end ?..or does it ‘straighten out’ and leave the flute in a straight line ??
Any ideas anyone ??..bye for now…weedie…
Weedie! What’s up, bra? Missed you around here lately man.
Anybody know what happens to the wind? I’d like to know too. Sitting here noodling around on the Olwell Eb and wondering the very same thing.
Hmmm, my thoughts?
Well, it might spiral, as an interesting thought, or, then again, it might simply blow its way on through.
Apparently there’s also some of it which escapes through whatever tone hole(s) which might be vented.
There’s probably a scientific answer, yet perhaps that couldn’t diminish the final outcome: music.
I’ll leave it at that.
Hey there Mr Liney Bear 
…I’ll have to ask you what exactly IS a Liney Bear one day…A Bear that’s a Linesman ??? A bear with lines on it ??A bear that waits in a queue ???
But,for the moment,we 'll have to wait for an answer from the Flutey Boffins…
Weeds! Glad to see you still kicking arse in the outback.
My speculation about what happens to the air is pretty similar to Cork’s but I’d love to see a graphic or image or something from some scientist-y or engineer-y C&F type that’s super specific so a clod like me could understand it.
Hijack: A Liney Bear (formerly stray, currently gray [and likely to stay] kitty named Linus) looks like this:
If it’s all that important, try blowing some smoke through one of those clear, Crystal Hall glass flutes, and then see what happens, perhaps with the aid of a mirror.
Then, extinguish the smoke, please.
Maybe we can ask this guy!
According to his profile:
Location: Dublin, Ie or Portland, Or
Website:
Occupation: Student/Full-Time Asshole
Interests: Flute, Whistle, Bouzouki/Mandolin, and poking smot
Maybe there’s a youtube clip?..
Just a hunch, but weedie, do you have anything, uh, in common with Unseen? 
Smot Poker ?? Me ??.. 
…to be sure,my name must surely come from the bait that I use to catch the fish, Luderick,They eat this green weed see !! It grows in the local creeks…Thats my story and I’m stickin’ to it 
So …its a puddy dat…not a bear at all…got it now mate
G’day Cork…yes,the smoke in a clear tube. That would be pretty conclusive I reckon…
Indeed, it does spiral for the first bit, then iron out. You can put a toothpick in the middle of the flute with no greatly noticeable effect. But if you put it in the head joint near the embouchure where the air stream is spiraling, it will mess with the aerodynamics. In the middle of the flute, the air stream hits the toothpick end on, but in the head it hits it amidships.
Terry
Sounds like a tune title! Much more industrial then The Lark in the Clear Air. 
Of course, remember, smoke gets in your eyes…
from what little i know about acoustics, i would say once it stables out it would have to go back and forth, actually. the sound “waves” as we call them have to consist of both high and low pressure. this means, that within the system of a flute, that the air in the headjoint/embouchure is creating both higher and lower pressure fluctuations compared to a pressure of "zero’ (or that of the room). as air travels down the flute, it must come back, as all reactions must have an equal, and opposite reactions. so, the air that makes it to the end of the system (which changes as keys/holes are opened), inevitably must send some sort of reaction in the opposite direction of the opposite pressure. or, in other words, as air is pushed out, a low pressure “wave” is sent back, a result of air being pushed out.
or to answer your question, the system of pressure is very stable and does not spiral. the actual air particles themselves are probably very chaotic, as air molecules themselves are kind of chaotic to begin wit.
for those who know more, is that a fairly accurate description?
Well, ya…the “average” flow spirals a bit and flows down the tube…while the “dynamic” flow (or sound pressure/flow wave) bounces back and forth. The “average” flow is one of the things that can be used to flatten the pitch.
PS: this is one way we used to make acoustic flowmeters
Thanks for the replies Terry,Daiv and Jack…The wind in the tube certainly has a busy time making our music !!! I thought there’d be a ‘scientific’ explanation about this..
Jem…I eagerly await your composition “The Smoke in a Clear Tube” ..
Another tune/song with a smoke theme is the beautiful “Smoke Dreams of You”,written in 1938 by Jack Gibsone and Derek Faulks…
best wishes..weedie…
Who has seen the wind?
Neither I nor you;
But when the leaves hang trembling
The wind is passing through.
Who has seen the wind?
Neither you nor I;
But when the trees bow down their heads
The wind is passing by.
- Christina Rossetti
Very simple…and very nice…lovely stuff MT…and Christina..
Flute Acoustics is a very “Deep” subject. You can find some answers here…
http://www.phys.unsw.edu.au/jw/fluteacoustics.html
http://www.phys.unsw.edu.au/music/flute/
The airstream works as an oscillating siphon and the depth of the embouchure chimney is used specifically to cancel the spiral flow and make it more linear. If you are looking for a more specific answer to a question, I am your humble servant…
P.S. The light stays on in the fridge to scare away the cockroaches, everybody knows that!
Ah… so much for mystical sonnets about passing wind. 
That seems to nail it down to a plank nicely. Ain’t IT grand?
Thankee for the interesting info!