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ideas for wind turbines
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| Psiclone 2006-02-19, 5:21 am |
| has anyone ever tried to fly a windmill from a 4 way tethered balloon
instead of building a tower?
run a hose up to it along one of the tethers to keep it filled with
hydrogen...
i've seen cellphone towers that are hung from balloons somewhere. i think
they had a 13 mile range
--
....Set phasers on tickle!
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| nicksanspam@ece.villanova.edu 2006-02-19, 8:21 am |
| Psiclone <nunya@biz.net> wrote:
>has anyone ever tried to fly a windmill from a 4 way tethered balloon
>instead of building a tower?
Why not?
An Air X weighs 13 pounds, and air weighs 0.075 lb/ft^3, so we might lift
it with about 13/0.075 = 173 ft^3 of H2 from an electrolyzer (2 carbon rods
from flashlight batteries?) on the ground or on-board a 20'x3.3' diameter
hot dog, eg a 12'x20' piece of 0.006 inch 4-year greenhouse polyethylene
film with 1x3s or PVC pipes to seal the edges.
Or use 40' ($22) of 30" diameter poly film duct from a greenhouse supplier
to make 2 hot dogs and fly the Air X from a pipe suspended between them.
The H2 permeability of low-density polyethylene film at 25 C is 8 x 10^-13
cm^3 cm cm^-2 s^-1 Pa^-1, ie 8 x 10^-13 cm^3/s of H2 would flow through
a 1 cm x 1 cm x 1 cm thick piece of poly film with a pressure difference
of 1 Pa. The duct hot dog walls would be 0.0152 cm thick, with 314 ft^2
(29 m^2 or 292K cm^2) of surface. Greenhouse film is often pressurized to
0.25 "Wg, ie 844 Pa, so about 8x10^-13x292K/0.0152x844 = 0.013 cm^3/s of
H2 would leak through the walls, ie 0.00013 liters/second, ie 0.46L/h.
Perhaps we could also sell ad space.
Nick
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| Harry Chickpea 2006-02-19, 12:21 pm |
| "Psiclone" <nunya@biz.net> wrote:
>has anyone ever tried to fly a windmill from a 4 way tethered balloon
>instead of building a tower?
>run a hose up to it along one of the tethers to keep it filled with
>hydrogen...
>i've seen cellphone towers that are hung from balloons somewhere. i think
>they had a 13 mile range
The drag forces anything like that down. The only fixed point is the
tether. Also, I think you might have seen an antenna hung from a
balloon/kite, but I doubt you saw a cell tower hanging from one.
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| Psiclone 2006-02-20, 2:21 am |
| "Harry Chickpea" <hchickpeaREMOVEME@hotmail.com> wrote in message
news:43f994cf.7833208@news.east.earthlink.net...
> "Psiclone" <nunya@biz.net> wrote:
>
>
> The drag forces anything like that down. The only fixed point is the
> tether. Also, I think you might have seen an antenna hung from a
> balloon/kite, but I doubt you saw a cell tower hanging from one.
kites stay aloft on a tether. what if it has a wing that can be angled to
use the wind to keep it up instead of getting driven down. maybe the balloon
itself could be specially shaped...
and... oh yeah i mean a transmitter/receiver system not a tower hanging
from a balloon sorry i was tired. i'm so excited to be back on usenet. i
stayed up waay too late last night. thanx for picking up the stitch...
none of these are tethered... i'll look more later i know i saw a cigar
shaped derigible repeater for cellphones that was fixed in place and had a
13 mile range. i'm going to breakout the webferret here in a while.
http://www.spacedata.net/netscape/p...s/apr232002.htm
http://www.g4tv.com/techtvvault/fea..._Reception.html
http://www.engadget.com/2006/01/31/...-for-north-dak/
....bluewave mailreader tags are history;)--me
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| barry@sme-online.com 2006-02-20, 11:21 am |
| You might have problems with aviation authorities. E.g. not far from me
is an approach path to an airport, with regular "heavy" traffic. They
might get testy about what amount to barrage balloons in their path.
:')
J
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| Harry Chickpea 2006-02-20, 12:21 pm |
| "Psiclone" <nunya@biz.net> wrote:
>kites stay aloft on a tether. what if it has a wing that can be angled to
>use the wind to keep it up instead of getting driven down. maybe the balloon
>itself could be specially shaped...
I think that is already being done. I checked this out a few years
back. The forces involved in generating any significant power are
just too much for a kite/balloon to handle.
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