Rear Wing Vibrations

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Emerson.F
Emerson.F
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Joined: 20 Dec 2012, 22:25
Location: Amsterdam

Rear Wing Vibrations

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Hey guys was this normal? I was scared that wing would just break off at any moment.

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Shrieker
13
Joined: 01 Mar 2010, 23:41

Re: Mercedes AMG F1 W05

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I thought the same. They showed a similar shot (not the exact same angle and zoom) of Nico's car at the same place, his rear wing definitely wasn't wobbling as much. In fact it wasn't even close, the wobbling on Lewis' car (as seen above) was extreme.
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Burgess
Burgess
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Joined: 03 Jan 2013, 04:46
Location: Bath, UK

Re: Mercedes AMG F1 W05

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The rear wing on the 04 wobbled a lot as well.

user001
user001
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Joined: 29 Sep 2012, 15:55

Re: Mercedes AMG F1 W05

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I've seen this for years on f1 cars. seems to be "normal"

Lycoming
Lycoming
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Joined: 25 Aug 2011, 22:58

Re: Mercedes AMG F1 W05

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They don't seem to care too much about whatever effects the wing wobbling around causes, so I guess as long as it doesn't break, it's good to go.

JesperA
JesperA
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Joined: 27 Jan 2014, 21:18

Re: Mercedes AMG F1 W05

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Well, everything in the physical world have a natural resonance frequency, flutter, self oscillation etc, it does not mather how structural sound it is, you can make a huge concrete beam that is stiff like hell, but like in the public stands in stadiums where the audience is jumping in unison you can get a concrete beam to deflect violently thanks to its natural frequency etc amplifying the effect. Obviously it can fail but in case of the Mercedes its probably not a huge worry.

We have seen that many times before, front wings, tires, headshake, steering, crawling (or snaking) etc and i can't remember anytime that they made a design change to "fix" it, if you fix it, the only result 90% of the time is to move the natural resonance, self oscillation etc to another frequency but it will still shake in that new frequency :P

YUL-F1
YUL-F1
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Joined: 20 Jan 2014, 19:55

Re: Mercedes AMG F1 W05

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Emerson.F wrote:Hey guys was this normal? I was scared that wing would just break off at any moment.

https://31.media.tumblr.com/3796a3e213f ... o1_400.gif
I wonder if each wobble is triggered by downshifts of the gearbox while under heavy braking.

e30ernest
e30ernest
27
Joined: 29 Feb 2012, 08:47

Re: Mercedes AMG F1 W05

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YUL-F1 wrote:
Emerson.F wrote:Hey guys was this normal? I was scared that wing would just break off at any moment.

https://31.media.tumblr.com/3796a3e213f ... o1_400.gif
I wonder if each wobble is triggered by downshifts of the gearbox while under heavy braking.
My guess is a combination of wind direction, wind speed and road vibration caused this. I don't recall seeing this later on the race or on other parts of the circuit so it was probably just a freak occurrence.

simieski
simieski
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Joined: 29 Jul 2011, 18:45

Re: Mercedes AMG F1 W05

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As others touched upon, it's nothing to worry about, just the rear wing resonating. In FP1 there was a slow-mo of vettel's car doing exactly the same. Reasonably certain it isn't downshift related.
Thank you to God for making me an Atheist - Ricky Gervais.

Emerson.F
Emerson.F
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Joined: 20 Dec 2012, 22:25
Location: Amsterdam

Re: Mercedes AMG F1 W05

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YUL-F1 wrote:
Emerson.F wrote:Hey guys was this normal? I was scared that wing would just break off at any moment.

https://31.media.tumblr.com/3796a3e213f ... o1_400.gif
I wonder if each wobble is triggered by downshifts of the gearbox while under heavy braking.
I was thinking the same, but i may just be bumpy because the rear wing is attached to the rear suspension arms and the vertical strides next to the exhaust.
Supporting: Ham/Alo/Kimi/Ros/Seb/Hulk/Ric/Mag

timbo
timbo
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Joined: 22 Oct 2007, 10:14

Re: Mercedes AMG F1 W05

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Emerson.F wrote:I was thinking the same, but i may just be bumpy because the rear wing is attached to the rear suspension arms and the vertical strides next to the exhaust.
The wing can not be attached to the suspension.

n_anirudh
n_anirudh
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Joined: 25 Jul 2008, 02:43

Re: Mercedes AMG F1 W05

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YUL-F1 wrote:
Emerson.F wrote:Hey guys was this normal? I was scared that wing would just break off at any moment.

https://31.media.tumblr.com/3796a3e213f ... o1_400.gif
I wonder if each wobble is triggered by downshifts of the gearbox while under heavy braking.
Williams was looking equally bad.. I am sure you all have seen this:
[youtube]http://www.youtube.com/watch?feature=pl ... dr9g#t=107[/youtube]

Ninners
Ninners
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Joined: 18 Apr 2014, 18:19

Re: Mercedes AMG F1 W05

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It happens in the turbulent air of another car, the wing starts vibrating a lot as a result.

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turbof1
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Re: Rear Wing Vibrations

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Does the loss of the beam wing has anything to do with this? Loosing the rigidity it gives to the rear wing?
#AeroFrodo

flyboy2160
flyboy2160
84
Joined: 25 Apr 2011, 17:05

Re: Rear Wing Vibrations

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There are a couple of things that could be involved. If you have separated flow off the back of a bluff body, the vortices shed in that wake can oscillate back and forth. This can couple with one of the natural frequency mode shapes of the structure, giving you that back and forth motion.

I suspect, but can't prove because I have no F1 aero experience, that perhaps this oscillation could also be tripped by a temporary disturbance to the airflow to the rear wing (Ninners point) and to the vertical end plates, temporarily separating the flow off them. Once started, the vortex shedding could again couple with one the structural natural frequency vibrations.

This vortex shedding/structural coupling is what induced the famous Tacoma Narrows bridge collapse in the 30s. One of the reasons bridge decks are "open" now instead of closed like the Tacoma Narrows bridge is to reduce the aero forces on the deck.

I suspect, but again can't prove, that the beam wing (and monkey seat) helped stabilize the whole back end airflow structure, so I see Turbo's point/question. And yes, the wing end plates without the beam wing support could be less rigid because they are longer.