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 Wind tunnel with 56,597km hour record bike
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Aure
Starting Member

France
16 Posts

Posted - 12/20/2012 :  02:09:10  Show Profile  Reply with Quote
Hi everybody!
In due to Mavic, I had the opportunity to test last week my record bike in a Wind Tunnel.
It show us lot a thing, and somes that could interested people here. And also, this show us that the profiled pedal have a really really low effet on the drag : they decrease the Cda by 0.004 m². And also that they don't change the air flow around and behind the shoes. So this prove the legitimacy for the 56,597 km record belong to the unfaired category



The other main thing is that, I'm now seriously thinking to break the 60km in the hour, still unfaired of course.

mhelander
recumbent enthusiast

Finland
384 Posts

Posted - 12/20/2012 :  02:46:27  Show Profile  Reply with Quote
Nice to have update, Auré.

Any graphs or charts for numbers of wind tunnel tests ?

I see you've modified your bike little for more streamlined form. Are those just fairings or do also stiffen the frame ?

Cheers,
-Mika

Diy bents: Full-suspended off-roader @ 2012, Vendetta clone @ 2012
Commerials: MetaPhysic 700c @ 2011, M5 CrMo Lowracer @ 2010
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LongJohn
recumbent guru

China
581 Posts

Posted - 12/20/2012 :  05:47:01  Show Profile  Visit LongJohn's Homepage  Reply with Quote
Would love to see your results Aure!

I have started building the bike we talked about on the plane... :-)

Thomas
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Speedbiker
human power expert

USA
3835 Posts

Posted - 12/20/2012 :  06:47:23  Show Profile  Reply with Quote
Thomas and Aure talking bike design? Yikes!!! Go for it, guys!
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Larry Lem
human power expert

South Sandwich Islands
2538 Posts

Posted - 12/20/2012 :  06:57:54  Show Profile  Reply with Quote
My response upon learning that the foot fairings did not help much would have been, "Damn, I wish I hadn't gone to all that trouble to make them, let alone use them causing my record run to violate the the WRRA rules since the shoe fairings did not help significantly".

Ah well, your performance stands by itself whether one organization or 20 organizations exists as do all performances.

Larry Lem
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Aure
Starting Member

France
16 Posts

Posted - 12/20/2012 :  08:31:53  Show Profile  Reply with Quote
@ Larry.
Concerning, the profiled pedals and WRRA rules.
WRRA rules : "The vehicle construction shall be such that its shape does not overtly direct airflow around the rider's body, nor attempt to reattach the airflow behind the rider by use of tail fairing devices"

On more time, I notice that my profiled pedal follow the WRRA rules. They not direct aiflow around my body : even if they are touching the bottom of my shoes they are not touching my body. Since when my shoes belong to my body ? I can change of shoes but not of feet... And also, they are not direct airflow around my shoes, the only attempt is to clear the aiflow in front of the shoes, and this is one of the aim of all the profiled pedals, and until profiled pedals are allowed by the WRRA, I don't see what is illegal here.
Moreover, my profiled pedals, are not attempting to reattach the airflow behing the rider by a tail fairing device...

So, here, the wind tunnel tests show us that my profiled pedals respect the WRRA rules, like the Nocom ( like I saw it on an other post) : the aiflow is not cleared around or behind the rider body.
They have a tiny positive impact on Cda, and clean airflow a little bit in front of the shoes, like profiled pedals should do it.


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tim_turner
recumbent enthusiast

USA
233 Posts

Posted - 12/20/2012 :  09:02:14  Show Profile  Reply with Quote
so, what's your final calculated CdA?

T
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FredBailey
Starting Member

USA
1 Posts

Posted - 01/19/2013 :  02:28:23  Show Profile  Reply with Quote
Wow,Your bicycle is so cool and I think you felt nice and different while practicing in wind tunnel.


Fred Bailey
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sircabas
Starting Member

France
7 Posts

Posted - 01/21/2013 :  02:33:38  Show Profile  Reply with Quote
Following the drops, I am led to believe that profiled pedals of Aure conform to the rules in force within the WRRA:
They do not lead the airflow to work around his body,
They thin only the resistance to abrasion to his shoes and
This is the goal sought and provided by the profiled pedals authorized by the rules governing other cycling disciplines.
Wind tunnel testing demonstrate a modest advantage of the impact on the cda;
just as important it profiled pedal offered in trade for the rest.
If the opportunity to acquire this kind of pedal profiled, specific to the recumbent, became effective in trade,
would you be willing to review your judgment on the record performance of Aure you hold negative, when do you think?
I thank you. Didon
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Speedbiker
human power expert

USA
3835 Posts

Posted - 01/21/2013 :  07:23:23  Show Profile  Reply with Quote
To continue arguing the legality of Aure's pedals is pointless. The WRRA rules commitee ruled them NOT legal. Hence, while Aure is a great guy, and his performance amazing, his ride is not an official record according to any organization I know of.
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sircabas
Starting Member

France
7 Posts

Posted - 01/21/2013 :  08:46:17  Show Profile  Reply with Quote
quote:
Originally posted by sircabas





Thanks for your timeliness but it does not let in and does not want to accept your decision feeling in his good right and me being in doubt your impartiality
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warren
human power expert

USA
6423 Posts

Posted - 01/21/2013 :  09:24:23  Show Profile  Visit warren's Homepage  Reply with Quote
While Thom is well respected, he is not on the WRRA committee. If you would like further review of this record, please email the WRRA committee. As far as I know, Aure has not even submitted the minimum documentation required to be considered. This was all spelled out to him well in advance of the event. One of the requirements was as picture of the bike. I don't think we saw that until a few days before the event and we told him the foot fairings would not be WRRA legal. Also, please send the committee members the results of the wind tunnel testing with and without the shoe fairings. We will review.

-Warren.
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mhelander
recumbent enthusiast

Finland
384 Posts

Posted - 01/21/2013 :  22:49:27  Show Profile  Reply with Quote
+1 for fair treating in WRRA.

I appreciate reviewing in such details like detailed pictures and wind tunnel results. This is great learning possibility for us all ! And big thanks for Auré for publishing those results and pictures.

Cheers,
-Mika

Diy bents: Full-suspended off-roader @ 2012, Vendetta clone @ 2012
Commerials: MetaPhysic 700c @ 2011, M5 CrMo Lowracer @ 2010
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sircabas
Starting Member

France
7 Posts

Posted - 01/23/2013 :  04:16:45  Show Profile  Reply with Quote
I you thank for your reply Warren, I remember your attention again,

I'd still like to make a clarification, and this is not about the days that a record is beaten:

With the pedals of Auré, the pedalling action always meet the resistance of the air, It is not sheltered behind a fairing itself, penetration into the air is facilitated by a drawing of the recumbent-specific contoured pedal, a convex form.

No one will have the idea to reject the study accomplished by the hull of a boat which facilitates its penetration in the water to witness to the raft!

No one will have the idea reject the adaptation of the Yonex to the race in the snow prevents to sink less than market in snow up to their knees!

As the hull of a boat, snow Yonex, the same stilts that allow walking in thickets, Auré pedals can be validated.

The record was beaten, it is a fact >>> http://www.dailymotion.com/embed/video/xr5qrt ,

evidenced by official identified,


>>> http://didier.arlabosse.free.fr/Record_heure/

a video, you can longer reject this whole.

When do you think? Thank you.

_ Didon
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warren
human power expert

USA
6423 Posts

Posted - 01/23/2013 :  07:59:16  Show Profile  Visit warren's Homepage  Reply with Quote
What was the cda of the bike Aure? we can use that to calculate the speed difference with and without the pedal fairings at 50 kph.

Thanks,

-Warren.
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Zyzio
recumbent enthusiast

USA
163 Posts

Posted - 01/23/2013 :  09:45:41  Show Profile  Reply with Quote
I was curious and plugged-in some approximate numbers into the HPV calculator:

350W
Crr = 0.0026 (top tubulars on wood track)
CdA = 0.114 (picked to get into the approx. speed range Aure was riding) – 35.683 mph
CdA = 0.118 (w/o shoe boats) – 35.289 mph (-0.394 mph, or 0.634 km/hr.)


PeterB
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