Aerodynamics thread?

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recumpence
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Re: Aerodynamics thread?

Post by recumpence » Jul 11, 2008 9:23 pm

Wow, that is just weird! :shock:

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Re: Aerodynamics thread?

Post by TylerDurden » Jul 11, 2008 9:32 pm

Bob McCree has one... (no tailbox tho). I figger, why not? :mrgreen:
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Re: Aerodynamics thread?

Post by docnjoj » Jul 12, 2008 9:32 am

I've been eyeing Cruzbike conversion kit for years! Brilliant engineering! I may be too old to go back to 2 wheels, after 5 years on my trike! Aero idea looks real slick, and covers packages.
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Re: Aerodynamics thread?

Post by TylerDurden » Jul 12, 2008 1:34 pm

Testing flow illustrator:
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Re: Aerodynamics thread?

Post by michaelplogue » Jul 12, 2008 5:18 pm

Cool little tool you've found there! Thanks for the link. TD - it looks like one would be better off having the tail cowling come to a point rather than being rounded off.

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Re: Aerodynamics thread?

Post by Ben » Jul 13, 2008 1:48 am

Doesn't really matter, you've got an extra dimension to play with in real life. Just make the fairing come to a knife's edge vertically and it'll be fine.

You could try chucking the top view in the illustrator and see how it looks.

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Re: Aerodynamics thread?

Post by truckerzero » Jul 16, 2008 1:07 am

old saying :thers no substittute for cubic inches
new saying:thers no substittute for watts !!!
just kidding watts plus cda = top speed
ford explorer 12 mpg
pontiac sunfire 30 mpg
883 harley sportster 55 mpg
raze rc nitro buggy 196 mpg on 5% nitro methanol fuel
stryker electric rc plane 3.3 watts per mile@80 mph(too bad i cant ride on that thing)!!!

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Re: Aerodynamics thread?

Post by MidniteTweeker » Jul 17, 2008 1:40 pm

Evolution of aerodynamics? :P

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Re: Aerodynamics thread?

Post by jnuts » Jul 17, 2008 8:15 pm

TylerDurden wrote:Testing flow illustrator:
How did you get it to work? I keep getting 0 kb movies sent to me when I try to create one with a standard airfoil that is included in the web page.

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Re: Aerodynamics thread?

Post by TylerDurden » Jul 18, 2008 12:12 am

jnuts wrote:How did you get it to work? I keep getting 0 kb movies sent to me when I try to create one with a standard airfoil that is included in the web page.
I never used the test stuff, just uploaded a bitmap.

Check the controls for how many seconds you want the movie... IIRC, I made mine ~15sec.

It does spit back an AVI, so filesize will be big.

:?
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Re: Aerodynamics thread?

Post by Ben » Jul 18, 2008 1:55 am

jnuts wrote:How did you get it to work? I keep getting 0 kb movies sent to me when I try to create one with a standard airfoil that is included in the web page.
Yeah I get the same thing with anything I try (settings or object type).

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Re: Aerodynamics thread?

Post by paultrafalgar » Jul 18, 2008 2:44 am

MidniteTweeker wrote:Evolution of aerodynamics? :P

MT
Nice try MidniteTweeker, but you left out a stage:
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Re: Aerodynamics thread?

Post by TylerDurden » Jul 18, 2008 10:02 am

worked 4 me :?

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Re: Aerodynamics thread?

Post by jnuts » Jul 18, 2008 10:55 am

TylerDurden wrote:worked 4 me :?
Ack! I've tried it with IE and Firefox - both return 0 kb sized movies.

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Re: Aerodynamics thread?

Post by TylerDurden » Jul 18, 2008 11:32 am

PM sent, but others may have the same issue, so I'm posting here...

Hi folks,

Couple of thoughts:

Your ISP or firewall may be blocking the files

The codec is IV50 wich got broken in some versions of WinXP and Vista, you may have to download again and reinstall IV50.

HTH
Have a Nice Day,

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Re: Aerodynamics thread?

Post by jnuts » Jul 18, 2008 11:48 am

TD - thanks for the PM. I'm lost as to why it's returning a null sized movie. I sent an email off to the author.

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Re: Aerodynamics thread?

Post by michaelplogue » Jul 18, 2008 2:27 pm

I'm having the same problem. Just installed the codec mentioned above and am giving it another try.

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Re: Aerodynamics thread?

Post by jnuts » Jul 18, 2008 2:58 pm

It doesn't matter if you have the mother of all codec packs installed - if the file size is null, zip, zero, zilch, nada.... there is nothing to play. :)

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Re: Aerodynamics thread?

Post by TylerDurden » Jul 18, 2008 4:51 pm

Here is a link to the movie I downloaded from the flow sim:

http://paperstreetltd.com.p2.hostingpro ... rMovie.avi

Please download and verify it plays on your pooters.

Edit:

new link http://www.paperstreetltd.com/media/video/YourMovie.avi
Last edited by TylerDurden on Jul 18, 2008 7:29 pm, edited 1 time in total.
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Re: Aerodynamics thread?

Post by Ben » Jul 18, 2008 6:49 pm

Gah! I can download your movie and play it, but I still get that darn 0kb file thing happening when I try to make my own or download one of their movies.

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Re: Aerodynamics thread?

Post by jnuts » Jul 18, 2008 6:55 pm

TylerDurden wrote:Here is a link to the movie I downloaded from the flow sim:

http://paperstreetltd.com.p2.hostingpro ... rMovie.avi

Please download and verify it plays on your pooters.
Yep, plays fine here on media player classic.

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Re: Aerodynamics thread?

Post by paultrafalgar » Jul 19, 2008 3:26 am

Works fine on gxine on Debian Linux.
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Re: Aerodynamics thread?

Post by John in CR » Jul 29, 2008 12:58 pm

OK, I've had it with the wind slowing me down. My good road routes put me directly into a headwind to start every ride. While it's great for the return trip, it's time to get sleeker. In addition to a small front fairing and a tailbox, I want to do some little things that will hopefully add up.

Tires- These knobby off-road tires have got to go. I don't like them in the curves anyway, and they must be a real aero thief too. Whenever I lift the tire off the ground for a spin test it's like I'm turning on a powerful fan.

Front suspension- I forget the exact relationship, but something I learned in my sailboat design research is that a cylindrical form has the same aero drag as proper foil that is 3-4 times thicker. I want to build some AL or fiberglass sleeves to turn those front shock housings into air foils, along with something similar for any exposed tubular shapes.

John

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Re: Aerodynamics thread?

Post by docnjoj » Jul 29, 2008 5:18 pm

Thats a good idea, JohninCR! My tubing is square, and I have been thinking about airfoiling it with foam and fiberglas/epoxy. Nice little upside down wing like them Formula 1 cars! Im not sure I go fast enuff to get any real benefit, as most of my rides are under 25 mph!
otherDoc
E-bike stable at our house

Steintrike Mad Max full suspension trike rear Cute 100H going on: Whoops, Cute wheel broke but I fixed it.
Sun USX delta trike EbikeKit small geared front wheel sort of front suspension for wife

Agniusm/A123 AMP 20 36 volts on the Steini has been taken off.
2x16000 Multisport from HK now gone as they died after 2 years
New Luna 10S bottle battery 13.6AH now on mine
Relatively New 10S4Px2 for wife's bike giving 20ah @ 40 volts home made Panasonic from Tumich. BMS's rule.

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Re: Aerodynamics thread?

Post by recumpence » Jul 29, 2008 5:28 pm

I am looking at making a tail box this winter. What I would love to do is make a complete seat and tailbox. The seat would be made of thin layers of plywood curved and laminated together, then the entire seat would be covered in carbon fiber or fiberglass.

The tail section would be made of a piano wire structure MIG welded together, then cloth stretched over and epoxied. :)

So many ideas, so little time!

Matt
1% of the world's population can think "Outside the box". The rest are firmly stuck within the box. Where are you?

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