Korean GP 2010 - Yeongam

[mr moda]

Conjecture and speculation.

Nothing in 928's post sheds any new light on Seb Vettel's engine failure in the Yeongam GP. And it doesn't support the outlandish theory that the engine failed due to driver input. I call it off topic speculation.

But the outlandish theory that his garage of junior mechanics are to blame is quite rational eh?

[univex]

Conjecture and speculation.

Nothing in 928's post sheds any new light on Seb Vettel's engine failure in the Yeongam GP. And it doesn't support the outlandish theory that the engine failed due to driver input. I call it off topic speculation.

But the outlandish theory that his garage of junior mechanics are to blame is quite rational eh?

+1 Renault would be assembling the engine and most likely fitting it too. To that end it is probable that Renault would not even know if an engine is for Vettel or Webber when they build it.
Keep it up 928S. Good stuff.

[zeph]

Conjecture and speculation.

928, what you are saying has some truth, but it's a little exaggerated.

I have yet to hear a better explanation.

As far as I can tell, 928S' did not claim that this is what happened. He just says it is possible for a driver to unduly stress an engine and shorten its expected lifespan.

[forty-two]

Conjecture and speculation.

928, what you are saying has some truth, but it's a little exaggerated.

I have yet to hear a better explanation.

As far as I can tell, 928S' did not claim that this is what happened. He just says it is possible for a driver to unduly stress an engine and shorten its expected lifespan.

+1

928S' statements all sound perfectly feasible to my untrained ear.
We need more posts from you 928S!

[raymondu999]

Wasn't there a conspiracy theory sometime last year (when Red Bulls were blowing engines left right and center) that RB was getting 2nd-rate Renault engines? Kinda like Sauber/Toro Rosso?

[Dragonfly]

By Dragonfly

They use different engines and gearboxes for practice on Friday. And do relatively small number of laps during the last FP.
While you are right in general about how revs influence engine wear, your arguments about Webber and him preserving the engine better are weak.

That is not quite true either, the way you present these facts it is like the engines are not in the pool of 8 engines. The fact is that Webber engines have not failed in the races is because he is still able to use the high milage units in the times set aside for practice. So this keeps his engines fresh for the races. This is the reason that he was able to hold off to the Korean GP to use his last engine.

You're right about the pool but they never use except in extraordinary situation a practice engine for racing. In fact they do the opposite and I wanted to point out the fact that Vettel's engine which blew out is not the one he ran on Friday. As well as Mark's.
In fact IIRC Mark had two engine failures during practice sessions this year exactly because they use engines at the end or even beyond their expected lifespan.
On pure technical grounds I agree with you, more precisely I even can't and do not dare arguing as I don't have the qualifications of a mechanical engineer, nor any reasonable experience with high performance engines. So reading what you write in detail and particularity is a precious source for learning new things. =D>
But, as someone already said, I think you exaggerate the importance of driving style in real race conditions. And IMHO it's just a kind of bias towards a driver you favor more.
If Webber was so kind and caring towards his engines, he wouldn't be able to match not to speak about beating his teammate at certain races. And race conditions is what you miss as a factor. Sometimes it is absolutely necessary to go on max fuel and revs to keep your position and gap to the chasers. And teams take deliberate risks, win all or lose all, because simply giving up due to the need to nurse the engine is not acceptable.

This of course does not mean that I deny that there is a certain effect from driving style, but I think you give it much more importance than deserved. Because you cant be competitive to your team mate if you put nursing the engine on first place. Remember, margins are measured in hundredths and thousandths of a second. Short shifting places a driver out of those margins.

[donskar]

Thanks for this clear and informative exposition. I would like to read more posts of this caliber.

Stick around!

+1. Very interesting.

[ringo]

Well you all can believe what sounds nice and meaty, iunderstand that you haven't heard some technical stuff in a while and gobble it up one it gets here, but an engine is not designed on the borderline.
928 knows the details of an engine, in fact it sounds like he works with them, and he can present the terminologies and jargon very well, but unless there is mathematical evidence to differentiate Weber's driving to Vettel's then it's specualtion.

Pressure vessels are not designed on the borderline. They have saftey factors of at least 3 or 4. For those who know fatigue theory as well, thermal factors are considered in the design, as well as surface finish, notches, cracks etc.
It's actually very predictable to determine when an engine will fail. Especially an aluminum part. I've never designed an engine, but i've done pressure vessels before and parts subject to alternating loads, such as shafts and wheels.

If the engine is perfectly assembled, it will do it's designed life. Whether it is assembled correctly or manufactured out of tolerance is the issue.

You have to look on it as 2 things here to fully understand why the driver is not to blame.
Look on it as a control system. Consider all the inputs and their limits.

Is Vettel's inputs different than Mark's mathematically? No.
The pedal presses have the exact same functions, and the paddle shifts are but button presses.
Does Vettel's inputs have higher or lower limits than Mark's? No.
He throttle displacement has the same range and accuracy, his engine has the same rev limit.

Secondly the factor that cannot be accounted for are the mechanics/engineers/technicians who work on Vettel's engine; be they Renault engineers or Redbull. Those are Human elements and cannot be quantified.
I would more blame them than Vettel modulating his inputs within their limits.


Before we go into more detail which part exactly failed on Vettel's car?

[ringo]

Conjecture and speculation.

928, what you are saying has some truth, but it's a little exaggerated.

I have yet to hear a better explanation.

As far as I can tell, 928S' did not claim that this is what happened. He just says it is possible for a driver to unduly stress an engine and shorten its expected lifespan.

So if a mechanic leaves a rag in the water pump, you need a better explanation as to why an engine overheated?
It's not possible for a driver to unduly stress an engine to 3/4 it's life span.
His engine is not more powerful, and what ever else he can do to stress the engine, doesn't create such a reduction in the fatigue life.
I'll give an example later, i'm feeling a little to lazy to do it now.

[WhiteBlue]

The Korean GP was a great success as an event. The track and all facilities were finished in time for the race, the track proved to be challenging and unique and the inaugural event drew a crowd of over 80,000 on race day.

http://www.gpupdate.net/en/f1-news/2459 ... t-f1-race/?

I watched all sessions and must say that I seldom saw such entertaining free practise all year long. The dry qualifying was also action packed and very enjoyable.

[xpensive]

...
If the engine is perfectly assembled, it will do it's designed life. Whether it is assembled correctly or manufactured out of tolerance is the issue.
...

Within mechanical engineering in general and tribology in particular, it is very difficult to establish a "designed life" per se,
other than a statistically estimated nominal lifespan, typically within a normal distribution with a certain variance.

For xample, roller bearings have their lifespan estimated through ISO 281:1990, which gives you the xpected nominal lifespan for 90% of the population for a given bearing-type and loadcase.

The above is all dependent on assumed conditions and as always within any kind of engineering, the question is how far you will trust your loadcase estimations and calculations, in other words, what margins to apply to your nominal values.

[ringo]

There are equations that you can use. Endurance limit theory.
You know your alternating stress and you max and minumum stresses, you find your mean stress and use a soderberg diagram. I'm a little fuzzy on it, but i just have to do a refresher to sharpen up.

Here's a simple soderberg diagram:

http://www.efunda.com/designstandards/s ... ue_eqn.cfm

Using this along with an SN curve and notch sensitivity curve engineers can predict pretty much any case.



you can have fatigue strenght for:
rotating bending, reversed bending, reversed axial loading, torsional loading, bi axial loading ect.

There are so many factors that the teams account for; surface, load type, gradient(shape) temperature, reliability, it's difficult to think the wont account for these already established factors on their super computers.
These factors go into the overall stafety factor, to ensure that the part is not on the borderline borderline.

Tribology is one thing i don't really go into, but i believe the oil and fuel makers have their thing covered.

There is too much data at the engineers disposal for an unpredictable failure.
The least predictable thing and hardest to quantify is the human element. This is mostly how machines fail. So i am more eager to blame the engineers and mechanics, who assemble the unit than blame the driver activating inputs than can only be operated in a limited way and come with many fail safes and fool proofs.

[marcush.]

the fact that you are somewhat disconnected from the engine due to drive by wire and ecu routines avoiding some actions that would lead to an instant failure ,It is more than evident that you have the opportunity to punish your material harder than others ,no doubt about it.1km Webber certainly is a different set of happenings compared to vettel.And a variable is what it is ...it creates differences.In most cases this might be minor ..in our case we see more issues with Vettel.

[ringo]

This is why i think Vettel's side of the garage is responsible. It's always Vettel's car. I'm glad it is though, becuase he would walk away with the championship.

Let's suppose both these drivers have a binary switch to press that only outputs a 1 or 0. No matter how hard vettel smashes the switch, destroying it if he wants to, it will only output a 1 or 0. It can't transfer the harshness of vettel's button mashing, it is limited to 1 and 0. The same can be said of Webber.
The engine cannot differentiate between the 2, and will simply opperate according to it's design or manufacturing quality.

[donskar]

I've got to be missing something here, because I am totally bewildered. Am I the only one that believes this discussion fails to account for the DRIVER as a factor in engine life?

To exaggerate for effect: I get the feeling that some of you want us to see the driver as putting his foot to the floor for 200 miles, shifting at max revs, keeping the engine at the red line and that's it. But the engine is not a "binary switch." It is not just Off or On, there are variations in the amount of On.

There are many variables to how a driver uses an engine. Example: smart drivers (Phil Hill, Alain Prost, for example) drive only fast enough to win a race. Once they have the race in hand -- or are hopelessly out of contention -- they'll short shift, back off before the end of a long straight, they'll make sure they don't follow another car too closely for too long, in order to keep the engine's temp under control, etc. Their engine runs fewer revs and spends less of its life on the ragged edge. They will put less stress on their engines than the driver who drives as hard as he possibly can regardless of the situation (example: the driver in 5th or 6th -- or 1st -- who goes all out on the last lap to set a lap record).

I say that a careful/smart driver can manage his engine just as a good driver can manage his tires. But that just MHO.