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PostPosted: Thu Jul 12, 2012 12:53 pm 
Retro Guru

Joined: Wed May 27, 2009 10:41 am
Posts: 637
http://vimeo.com/45034602

Interesting.


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PostPosted: Thu Jul 12, 2012 3:28 pm 
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Joined: Sat May 22, 2010 10:33 pm
Posts: 2192
Location: Suffolk
Laz you asked where one eyed jim's statement of power increases with speed ubed ome from.

If it has not been answered already (I may have missed it) and if you have not found already then it ome from here.

F = 1/2CdApv^2

As P = Fv

the P = 1/2CdApv^3

F= drag force
Cd = coefficent of drag
A = frontal area
p = density of air (~1.2kg/m^3)
v = velocity
P = power output.

To do this properly I figure windtunnel testing of various scale designs is needed to work out Cd. It an be done with computor modelling though with the right software. A university areospae department might be able to help. Could make a good final year thesis for someone.

I also think a fairing of some sort will be needed to reduce Cd. It probably does not need a fully enlosed fairing either. Sale model testing would answer that.


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PostPosted: Sat Jul 14, 2012 10:36 pm 
Retro Guru

Joined: Sun Mar 27, 2011 11:36 pm
Posts: 551
Location: Liverpool
Hi John, Kp, bm :-) Sorry haven't got back to this, but it is still firm in my mind. Just got so much stuff to get through right now, but suffice to say no bull "I'm considering buying a sheet of titanium and having a crack at building my design (give or take). Also trying to source sheet carbon fibre. If all fails I'm going to knock up an aluminium/stainless steel/ reynolds-columbus tubing version. I can test the theory without it costing an absolute fortune :-) It'll give me something to do now I have admitted I was addicted to owning bikes, breaking the spell by selling the collection, and am happy to just pour my last efforts in life into designing something new with a taste of old in it :-)

I say we keep this thread alive, it'll certainly give us all something to smile about (as I crash no doubt at speed) when she falls apart :-) Still, they say half the fun is taking part, the other 90% is winning :roll: :wink: Later everybody, Laz.

PS: thanks bm, all I have to do know is decipher what it means in english (I joke buddy)


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PostPosted: Sun Jul 15, 2012 12:52 am 
Dirt Disciple

Joined: Sat Jun 16, 2012 4:17 pm
Posts: 59
Location: Isle of Man
Hi Laz,

Good to hear from you, I saw your big sell off and wondered what the driving reason behind it was...

As for Carbon fiber there's a Firm in Blackpool (I think) that specialize in Composit Kevlar and fiberglass supply, you may find them with a google search.

If you get no joy I can get you the firms name on Tuesday, I heard about them via the Sidecar people here who use them to supply the raw material for fairings and undertrays.

May I also be the first to wish you my congratulations in deciding to go ahead with your project.

Could i also suggest making some scale models first to test your air resistance theory's, as a rule its usually easier to quantify early designs by checking the results for scale models.

John


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PostPosted: Fri Nov 16, 2012 4:23 pm 
South East Deputy AEC
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Joined: Mon Feb 22, 2010 7:27 pm
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Location: Angmering
has this moved on any more?

just read the whole thing, absolutley spell bound. Looking forward to getting home to watch the vids away from the Fun Police at work


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PostPosted: Fri Nov 16, 2012 5:14 pm 
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Joined: Thu Jun 23, 2011 11:25 pm
Posts: 1785
Location: It's not easy being a dolphin.
Last I heard was that he did not go the USA. Wasn't ready basically, but would attempt it in the UK sometime in the future.


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PostPosted: Sat Nov 17, 2012 12:21 am 
South East Deputy AEC
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Joined: Mon Feb 22, 2010 7:27 pm
Posts: 4397
Location: Angmering
I'm a little embarrassed to say, but I'm more interested in Lazarus!


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PostPosted: Wed Nov 21, 2012 11:59 am 
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Joined: Thu Jun 23, 2011 11:25 pm
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Location: It's not easy being a dolphin.
http://www.humansinvent.com/#!/9726/gra ... irst-time/


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PostPosted: Wed Sep 11, 2013 9:51 pm 
Dirt Disciple

Joined: Sat Jun 16, 2012 4:17 pm
Posts: 59
Location: Isle of Man
http://www.humansinvent.com/#!/13389/th ... e-special/


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PostPosted: Wed Sep 11, 2013 10:27 pm 
Dirt Disciple

Joined: Sat Jun 16, 2012 4:17 pm
Posts: 59
Location: Isle of Man
http://obree.com/obree-news.html


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