F1technical.net

saviour stivala wrote: ↑

21 Feb 2019, 16:36

wuzak wrote: ↑

20 Feb 2019, 06:47

Is there still oil vapour coming from Ferrari engines?

Today the fourth day of testing the FERRARI was still smoking driving out from the pit lane but not on track.

MarcJ wrote: ↑

21 Feb 2019, 09:08

Tzk wrote: ↑

14 Feb 2019, 23:14

It's about efficiency. You want as little weight as possible on the pistons and connecting rods, as this is wasted energy in a energy (fuel) limited formula. So in a perfect world you would reach the minimum weight, just as the teams try to with the whole car.

Having compatible thermal expansion between piston and liner, steel with surface finishing offering lower friction coefficient and piston skirt surface area reduced. The shape optimisations possible at operating temperature identified under numerical simulation at high mesh resolution only really limited by machine and tooling. Iterative optimisation they know the temperature and forces.

The kinematic behavior of the crank mechanism is improved, lower dead volume at top land, reduced blowby and more efficient combustion (less UHC, more complete) , K. Schreer "Analysis of aluminum and steel pistons" Journal of engineering for gas turbines and power.

The steel piston with or without tbc coating shown to improve combustion via various means, the surface temperature is more homogeneous.
With efficiency the #1 priority making steel pistons work was a priority to a big step change increase to overall engine efficiency.
TBC coatings on steel pistons are more durable than on aluminum, you can rely on the thermal behavior being consistent and improving combustion efficiency, lean limits and less coefficient of variance in the combustion phasing, less stresses on rotating assembly.

One thing to note with low temperature combustion with high bMEP is turning off the piston squirter leads to a 1.4% increase in Thermal efficiency, cooling the piston is killing TE.

roon wrote: ↑

22 Feb 2019, 04:00

MarcJ wrote: ↑

21 Feb 2019, 09:08

Tzk wrote: ↑

14 Feb 2019, 23:14

It's about efficiency. You want as little weight as possible on the pistons and connecting rods, as this is wasted energy in a energy (fuel) limited formula. So in a perfect world you would reach the minimum weight, just as the teams try to with the whole car.

Having compatible thermal expansion between piston and liner, steel with surface finishing offering lower friction coefficient and piston skirt surface area reduced. The shape optimisations possible at operating temperature identified under numerical simulation at high mesh resolution only really limited by machine and tooling. Iterative optimisation they know the temperature and forces.

The kinematic behavior of the crank mechanism is improved, lower dead volume at top land, reduced blowby and more efficient combustion (less UHC, more complete) , K. Schreer "Analysis of aluminum and steel pistons" Journal of engineering for gas turbines and power.

The steel piston with or without tbc coating shown to improve combustion via various means, the surface temperature is more homogeneous.
With efficiency the #1 priority making steel pistons work was a priority to a big step change increase to overall engine efficiency.
TBC coatings on steel pistons are more durable than on aluminum, you can rely on the thermal behavior being consistent and improving combustion efficiency, lean limits and less coefficient of variance in the combustion phasing, less stresses on rotating assembly.

One thing to note with low temperature combustion with high bMEP is turning off the piston squirter leads to a 1.4% increase in Thermal efficiency, cooling the piston is killing TE.

Construct the block and heads from steel as well. Allow the entire engine to run hotter. Reduce heat rejection to the radiators. Perhaps the rules preclude non-aluminum alloys from being used in this manner.

Is there any likelihood that steel combustion chambers (the upper portion) are being used toward similar benefit?

Power Unit in safe mode to avoid reliability problems. More exhaust arrangement to compensate for lack of CV. With a front end not at the height and so much understeer at the entrance of the curve in Australia you do not go strong, especially in qualifying.

Where do you think Ferrari's missing? It seems a lack of engine...

Phlumbert wrote: ↑

16 Mar 2019, 17:57

Not so sure on the validity on this:

https://twitter.com/SmilexTech/status/1 ... 35264?s=19

Power Unit in safe mode to avoid reliability problems. More exhaust arrangement to compensate for lack of CV. With a front end not at the height and so much understeer at the entrance of the curve in Australia you do not go strong, especially in qualifying.

"More exhaust" - I think the translation is wrong - should be "less down force".

Which was a reply to this:

https://twitter.com/mattiamaestri46/sta ... 5461935105

Where do you think Ferrari's missing? It seems a lack of engine...

f1jcw wrote: ↑

16 Mar 2019, 20:05

If their is a engine issue, why has it only effected Ferrari and not the customer teams.

LM10 wrote: ↑

16 Mar 2019, 20:16

f1jcw wrote: ↑

16 Mar 2019, 20:05

If their is a engine issue, why has it only effected Ferrari and not the customer teams.

The way I understood it was that it was Ferrari's own decision to have the engine in save mode not to risk anything. Better to go for points than to lose all of them. The customer teams might have decided for themselves to be in high engine modes.

• Kimi Q3 dropping RPM on his way to turn 11 (between 3:20 and 3:23) and complaining that he likely ran out of the 'K'.
  https://www.youtube.com/watch?v=ipI7g21 ... u.be&t=195

• Grosjean radio ''ran out of SOC twice'' in Q3:
  https://www.youtube.com/watch?v=9w_osfJvNrg

• Ferrari powered cars quite far down the speed traps:
  https://i.imgur.com/JFeWIkK.jpg

• Vettel doing a lot lift and coast which might get indicated by that green led:
  https://streamable.com/seq60

• Vettel RPM drop and asking about his PU:
  https://streamable.com/s19in

• Leclerc RPM drop (?) right under the Rolex ad:
  https://streamable.com/iro84

MtthsMlw wrote: ↑

17 Mar 2019, 21:59

Just gonna copy u/beckersCS post on reddit here.
Observations of the PU:

• Kimi Q3 dropping RPM on his way to turn 11 (between 3:20 and 3:23) and complaining that he likely ran out of the 'K'.
  https://www.youtube.com/watch?v=ipI7g21 ... u.be&t=195

• Grosjean radio ''ran out of SOC twice'' in Q3:
  https://www.youtube.com/watch?v=9w_osfJvNrg

• Ferrari powered cars quite far down the speed traps:
  https://i.imgur.com/JFeWIkK.jpg

• Vettel doing a lot lift and coast which might get indicated by that green led:
  https://streamable.com/seq60

• Vettel RPM drop and asking about his PU:
  https://streamable.com/s19in

• Leclerc RPM drop (?) right under the Rolex ad:
  https://streamable.com/iro84

Source

During the race we noticed a very cautious use of the Ferrari power unit, as if to confirm the post qualifying rumors, which spoke of a weakened engine to avoid technical problems in the race . Techniques that Ferrari had accused in the second week of testing in Barcelona.

Taking advantage of the work of Alex Brunetti (which you can find on his Twitter account), who followed the race from the pilots' onboard camera and heard all of Sebastian Vettel's radio teams, you may notice a quite unusual use of the Ferrari power unit.

The first strangeness concerns the narrow use of the mapping carried out in the first phase of the race. In fact, Vettel's Rossa goes off with the engine 1 mapping (which should be the most thrust), and after a few laps it passes to a much calmer engine map, engine 5. A very different choice than last season, when it went down gradually from mapping 1 to mapping 3-4. Yet at that stage Vettel had to stay close to the Mercedes duo so as not to let them escape.

The most extreme mapping (engine 1) is authorized only before the German pit stop, which took place during the fifteenth lap, in the race phase in which Ferrari was trying to fill the gap with Lewis Hamilton. This mapping is no longer used even during the defense on Verstappen, during lap number 31. In that phase of the race Vettel's SF-90 was set to a very bland engine mapping, engine 5, when normally, so as not to lose the position, you opt for the mapping engine 1, taking into consideration also the fact that the Dutch had mounted only a few laps the new medium rubber, compared to the yellow rubber already used by about fifteen laps by the German. This explains how Verstappen managed to "strip" the Ferrari into the straight that leads into turn three with a Honda power unit,

The quirks continue even in the middle phase of the race, when Vettel begins to "pull" the gears too much, especially on turn 13 and 14, to try to have higher engine revs, presumably to push the MGU-H to the maximum , as if there was a need to recharge so much, taking advantage of an extreme SOC (state of charge) mapping. A few laps later another Vettel radio team arrives in which he talks about "lag" in his power unit, thus a delay in power delivery, perhaps due to a non-perfect functioning of the turbo part?

Feelings relating to a problematic power unit are again recognized by Vettel, who at about twenty laps from the end asks Riccardo Adami if he is all right on his car and asks why he is going very slow, who dribbles the question saying that everything is ok. At the end of the race in Ferrari they decide to freeze the positions, not allowing Leclerc to overtake a Vettel in obvious difficulty