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Wind tunnel recommendation?

 

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Bodyflight.Net

Jun 10, 2005, 1:42 PM
Post #26 of 60 (1163 views)
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Re: [PhreeZone] Wind tunnel recommendation? [In reply to] Can't Post

Hey Phree!!

That's because you've never flown in a tunnel this efficient before! When air is this efficient and is being blown the burble closes itself almost immediately within a few feet..

When you add a second flying area.. comes a second net.. or in the case of AAC.. adding a tube to the bottom or airbag around the nozzle and jacking the net up a few feet.

With a 70+ foot air column, you can create up to 3 (theoretically) 2 for sure flight areas with 10 feet of seperation between the TOP of the bottom flight area and the BOTTOM of the top flight area, etc.. no burble.. no notice and NO ADDITIONAL operating costs!!!

OH.. and you'll STILL have more than 20feet of flyable area in each section!!! Come on out and give it a try!!


(This post was edited by Bodyflight.Net on Jun 10, 2005, 1:47 PM)


Paulipod  (B 1234)

Jun 10, 2005, 1:44 PM
Post #27 of 60 (1160 views)
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Re: [Bodyflight.Net] Wind tunnel recommendation? [In reply to] Can't Post

In reply to:
Anyway.. sorry about the noise comment.. I know that's a cheap shot... no one could ever be as quiet as we are while flyin!

Ahh thats OK - I just ignored it as I didnt want to point out for everyone to see that you didnt realise its not the motor that makes the noise LaughTongue


Paulipod  (B 1234)

Jun 10, 2005, 1:49 PM
Post #28 of 60 (1156 views)
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Re: [Bodyflight.Net] Wind tunnel recommendation? [In reply to] Can't Post

In reply to:
With a 70+ foot air column, you can create up to 3 (theoretically) 2 for sure flight areas with 10 feet of seperation between the TOP of the bottom flight area and the BOTTOM of the top flight area, etc.. no burble.. no notice and NO ADDITIONAL operating costs!!!

I have to say I am a little unsure how much of a nirvana this would be also... I cant imagine being the operator of a two level facility - what happens when things go wrong? or different sizes of people? (one speed fits all?!)

Must be one hell of a good booking plan to ensure everyone wants to do the same things on each levelCrazy

Still... does sound good not to waste air!


Bodyflight.Net

Jun 10, 2005, 1:50 PM
Post #29 of 60 (1155 views)
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Re: [Paulipod] Wind tunnel recommendation? [In reply to] Can't Post

OOOOOHHHHHHH.. that's dirty...
well.. the motor is certainly noiser than the air over here...


Paulipod  (B 1234)

Jun 10, 2005, 1:52 PM
Post #30 of 60 (1153 views)
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Re: [Bodyflight.Net] Wind tunnel recommendation? [In reply to] Can't Post

In reply to:
well.. the motor is certainly noiser than the air over here..

Its normally the fans / prop blades that make the noise... I just love being pickyLaugh


Bodyflight.Net

Jun 10, 2005, 1:53 PM
Post #31 of 60 (1152 views)
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Re: [Paulipod] Wind tunnel recommendation? [In reply to] Can't Post

Yes, Paul.. one speed fits all.. I've pretty much always subscribed to this theory.. there IS a magic number.. and it's not an airspeed.. it's volume...
That's why at AAC when I fly with 95 lb Rox and 170 lb Chris and my 130 lb frame.. we all fly together...

and it wouldn't be a nightmare at all!! we do it all the time without the extra net! Wink


Bodyflight.Net

Jun 10, 2005, 1:57 PM
Post #32 of 60 (1149 views)
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Re: [Paulipod] Wind tunnel recommendation? [In reply to] Can't Post

Quote:
Its normally the fans / prop blades that make the noise

nothing normal about this place...
http://www.verticalwind.com/2-1-05.html

unique and unusual!!Wink


Premier PhreeZone  (D License)
Moderator
Jun 10, 2005, 2:01 PM
Post #33 of 60 (1146 views)
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Re: [Bodyflight.Net] Wind tunnel recommendation? [In reply to] Can't Post

But the question is are you turning fast and hot 4 way points only a foot or two off the net, or are you flying around in the entire airstream using your body to make vertical adjustments?

I can't see too many 4 way teams wanting to fly in fast air based on my talking to a few team members with 100+ hours in the SV tunnels. If you are having to have the air at a speed that makes them happy you'll never be able to fly in other body positions unless I'm greatly missing something.


(This post was edited by PhreeZone on Jun 10, 2005, 2:02 PM)


Paulipod  (B 1234)

Jun 10, 2005, 2:02 PM
Post #34 of 60 (1145 views)
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Re: [Bodyflight.Net] Wind tunnel recommendation? [In reply to] Can't Post

Quote:
That's why at AAC when I fly with 95 lb Rox and 170 lb Chris and my 130 lb frame.. we all fly together...

Ok this I really dont follow. If you all hold similar body positions no way you are on the same level.... sure you can arch more / sit further back etc etc and keep flying together.... but thats not really the point...

If you have a group wanting to do 4-way on level 1 and a group wanting to freefly level 2 it doesnt work surely? If you have me a big porker wanting to fly on my belly and a small 14 year old wanting to do the same you dont tell the kid to arch more surely?

Am I missing the point? - And Airspeed and volume are directly linked so not sure what that means either? (probably having a blonde moment)


Bodyflight.Net

Jun 10, 2005, 2:09 PM
Post #35 of 60 (1134 views)
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Re: [Paulipod] Wind tunnel recommendation? [In reply to] Can't Post

Ok.. Volume is not the same as Speed.. not at all.. you can blow a small volume of air at a high rate of speed... (going to find my notes on this as I'm NOT an aerodynamicist).. that's why with the wrong size fan/prop you can blow the air fast enough but there won't be enough to fly on....

if you contain the bottom portion in a tube.. there is NO WAY the 2nd level flyers will ever notice they are there.. regardless of their discipline of choice..regardless of their size.. the air is NOT stoppable.. that's the beauty of a blower with this much efficiency..

(going to rummage through notes)


(This post was edited by Bodyflight.Net on Jun 10, 2005, 2:10 PM)


Paulipod  (B 1234)

Jun 10, 2005, 2:16 PM
Post #36 of 60 (1130 views)
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Re: [Bodyflight.Net] Wind tunnel recommendation? [In reply to] Can't Post

In reply to:
Ok.. Volume is not the same as Speed.. not at all.. you can blow a small volume of air at a high rate of speed... (going to find my notes on this as I'm NOT an aerodynamicist)

if you contain the bottom portion in a tube.. there is NO WAY the 2nd level flyers will ever notice they are there.. regardless of their discipline of choice..regardless of their size.. the air is NOT stoppable.. that's the beauty of a blower with this much efficiency..

There are a few basic problems with these statements. Speed and volume are different - yes quite true... but when you have a flow of air (constant) the volume that flows is in ratio with the speed of flow... so you cannot 'adjust' one without the other.... more airspeed - higher volume of flow... etc.

Secondly... you could consider the first flight area to be the air intake of the second... if I were to place a big sheet of metal slanting to one side in the airflow of the first area - absolutely the people in the second would notice higher speeds to one side than the other. You could probably argue that four peoples bodies cannot make a noticable enough difference but its not right to say they make no difference.... and I would have thought that you would be able to notice slightly (if I were a betting man!)

Smile


Bodyflight.Net

Jun 10, 2005, 2:26 PM
Post #37 of 60 (1128 views)
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Re: [Paulipod] Wind tunnel recommendation? [In reply to] Can't Post

the 'intake' is over 100 feet away from the flight area.. so it wouldn't work that way.. and I'm still diggin on my airspeed/volume.. while increasing one will increase the other.. it was my understanding that they are not the same..

and with seperation between flight areas.. I assure you no one would notice a thing.. so I hope your NOT a betting man..Smile

a person isn't comparable to a sheet of metal.. and even USING that sheet of metal scenario.. with enough seperation YOU STILL WOULDN'T notice it!
Because of the setup.. the air column maintains itself.. and correct itself

seperation is the key.. and there is pleny of vertical space to get oodles of seperation.. heck you could split them up by 20 feet even and still have 20 foot tall flight areas.. but there wouldn't be a reason to do that.

I wonder about the 4 way teams.. how in the world do they stay together in the sky without adding wieghts, changing body position or suit???


Paulipod  (B 1234)

Jun 10, 2005, 2:33 PM
Post #38 of 60 (1126 views)
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Re: [Bodyflight.Net] Wind tunnel recommendation? [In reply to] Can't Post

 
Ok Ok ... I am not a betting man but I would put you money on the sheet of metal making a difference! lol

Think of air as you would water (fluid and aerodynamics are the same bag) does the water from a shower head converge over space? air does much the same... if you have a hole or faster air in one place it doesnt easily correct itself.

Quote:
I wonder about the 4 way teams.. how in the world do they stay together in the sky without adding wieghts, changing body position or suit???

Simply put - they dont!

They wear weights - they change body position and need to do exactly the same things in the tunnel..... hence 2-levels would need to be well co-ordinated on speed setting.Smile


Bodyflight.Net

Jun 10, 2005, 3:05 PM
Post #39 of 60 (1117 views)
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Re: [Paulipod] Wind tunnel recommendation? [In reply to] Can't Post

Smile
Quote:
They wear weights - they change body position and need to do exactly the same things in the tunnel..... hence 2-levels would need to be well co-ordinated on speed setting

and this is where I get carried away every time! Believe it or not.. I don't think of skydivers as the primary source of income for any 'potential' tunnel.. there are only 30k or so worth in the US don't know about abroad.. while they CAN be an important source of income it's still minimal.. compared to the 4 million tourists, novices and tunnelrats available in a small geographical area surrounding a facility...

they don't care about all the stuff your talkin about.. don't know what MPH OR RPM they flew at.. could care less about volume and whos doing what anywhere else...... I would gladly fly about the 4 way team.. and the locals don't know any difference... yes coordinating would need to be done.. but it would hardly be a hassle at all.. we pretty much fly at 120mph no matter who is flyin... small children are different.. Lexi flys at only like 85 mph now.. workin her up though now....

Smile


Nicodemus  (D License)

Jun 10, 2005, 4:12 PM
Post #40 of 60 (1109 views)
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Re: [Bodyflight.Net] Wind tunnel recommendation? [In reply to] Can't Post

Now play nicely children... Tongue


(This post was edited by Nicodemus on Jun 10, 2005, 4:14 PM)


Bodyflight.Net

Jun 10, 2005, 4:21 PM
Post #41 of 60 (1105 views)
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Re: [Nicodemus] Wind tunnel recommendation? [In reply to] Can't Post

awww... c'mon... it's all good.. we're all friends!


adamUK  (C 104423)

Jun 12, 2005, 2:40 PM
Post #42 of 60 (1075 views)
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Re: [Bodyflight.Net] Wind tunnel recommendation? [In reply to] Can't Post

Sorry to be a saddo, but... The honeycomb (screen) and contraction are the bits that give you an even velocity profile across the test section (the bit you fly in), as you increase the distance from these, friction losses at the wall and between airflows at different velocities tend to produce a velocity profile that's much higher in the centre of the section than the outer edge, in the extreme, the centre velocity being twice the mean velocity.

Hence the reason why the 'fly' areas in wind tunnels tend to be just above the contraction. I would be surprised if your velocity profile remained consistent 70 ft up in a sub 15ft dia. tunnel.

"Internal Flow Systems" by DS Miller (1990) is a good introductory text to the behaviour of compressible flow, if you are interested!! It's also a good way of curing insomina as well. Tongue

love and kisses

Ad.


Bodyflight.Net

Jun 12, 2005, 3:31 PM
Post #43 of 60 (1066 views)
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Re: [adamUK] Wind tunnel recommendation? [In reply to] Can't Post

Quote:
I would be surprised if your velocity profile remained consistent 70 ft up in a sub 15ft dia. tunnel.

We wouldn't charge a million dollars for the technology if it weren't 'suprising' at least!Wink

ShockedOH.. and more importantly.. there is no honeycomb involved.. that would block the flow.. and we wouldn't want that!!!.. the air does not need to be straightened here like that!!!Cool

Everyone is still thinking traditionally.. this is not like ANY wind tunnel (vertical OR horizontal) anywhere in the world. The technology is NEW and VWTC is the only one who has it (operating in 2 tunnels). The system is custom designed from beginning to end.. build their own fan blads, hub, etc.... It took more than 10 years to perfect the technology. It functions in such a way that has previously been 'impossible' as everyone is pointing out. Smile

I am not sure in what terms I could provide evidence of this on here.. I'd be glad to accomodate if I can for sure!

That's what is so amazing about this tunnel.. the jet and the sound.. accomplish the IMPOSSIBLE, well WAS impossible.Tongue

Here are some tiny pics.. for you to see.. no honeycomb.. no turning vanes, and certainly nothing ordinary here.. and the pattern you see when looking UP through the hole is the net which is 25 feet or so above the nozzle opening. The nozzle is completely open.. so if you visit.. be careful or you'll fall in!!ShockedTongue Nothing on the floor and the fan is over 100 feet away (horizontally). It provides a horizontal test section as well and both can be used simultaneously without affecting the other one. Yes.. an utterly amazing feat has been accomplished here and the fan turns at an amazingly low 720 RPMs at FULL SPEED!

ok.. I'm done now.. I won't push this anymore.. you can PM me, anyone, if you seriously wanna hear more..
Attachments: collage.jpg (54.7 KB)


Paige

Jun 12, 2005, 4:36 PM
Post #44 of 60 (1060 views)
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Re: [adamUK] Wind tunnel recommendation? [In reply to] Can't Post

There is nothing related to the L1 that is anything less than incredible. You have to go check it out to really understand just how sweet the air flow is. It's very quiet compared to other tunnels and its fascinating to see someone flying above you, and someone above them, and then another stacked on top of everyone.

The L1 is an amazing engineering feat to say the least! L1 owner Chris Landen (sorry for a miss spell on the last name, I can't find it in print on the web site so I'm guessing) has one cool toy on his hands that he kindly shares with the rest of us.

Check out the L1 web site


tunnelfly

Jun 12, 2005, 7:45 PM
Post #45 of 60 (1051 views)
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Re: [Paige] Wind tunnel recommendation? [In reply to] Can't Post

In reply to:
Chris Landen (sorry for a miss spell on the last name, I can't find it in print on the web site so I'm guessing)

Chris Landon
http://www.verticalwind.com/balls.html
Right on the bottom...

(Sorry for being a smartass and showing off my knowledge of his website...Wink


Paige

Jun 12, 2005, 10:33 PM
Post #46 of 60 (1045 views)
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Re: [tunnelfly] Wind tunnel recommendation? [In reply to] Can't Post

In reply to:
(Sorry for being a smartass and showing off my knowledge of his website...Wink

Or instead showing off that you have way to much time on your hands TongueTongueTongueWinkSmileSmile I kid, I kid, it's all good Wink


Bodyflight.Net

Jun 13, 2005, 7:23 AM
Post #47 of 60 (1017 views)
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Re: [tunnelfly] Wind tunnel recommendation? [In reply to] Can't Post

OH GOSH... did you HAVE to use the BALLS page??
How embarrassing!! Tongue


tunnelfly

Jun 13, 2005, 8:51 AM
Post #48 of 60 (1003 views)
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Re: [Bodyflight.Net] Wind tunnel recommendation? [In reply to] Can't Post

Ok Dawn, next time I link the IMAGES page (the Euphoria page is WAY too noisy).

And Paige, what would you do if your employer sends you to Changchun (China), far away from any windtunnel or dropzone? Internet-Flying is the only option here! Unsure
I'm fully aware that the chinese invented parachuting (1306 A.D., when Fu-Chien became emperor), but they seem to have forgotten all about it...


(This post was edited by tunnelfly on Jun 13, 2005, 9:05 AM)


Bodyflight.Net

Jun 13, 2005, 8:55 AM
Post #49 of 60 (1000 views)
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Re: [tunnelfly] Wind tunnel recommendation? [In reply to] Can't Post

In that case, I'll upload our new L1 video from WindWorX... I was waiting on a final smaller compilation which is en queue but not yet ready...


tunnelfly

Jun 13, 2005, 9:14 AM
Post #50 of 60 (998 views)
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Re: [Bodyflight.Net] Wind tunnel recommendation? [In reply to] Can't Post

Oh, thanks, your my savior !!!
And size doesn't matter, the net is fast here!


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