F1technical.net

gruntguru wrote: ↑

31 Jul 2018, 02:52

godlameroso wrote: ↑

31 Jul 2018, 00:21

What if one of the benefits of having the flame initiated in the pre-chamber is that fire being electrically conductive, can actually boost the intensity and gap the spark can travel. For that matter I'm curious what kind of plug gaps they're using. High boost requires relatively small gaps, even with coil 'packs' so I wonder where the current trends are going.

If you already have "fire" you don't need a spark.

roon wrote: ↑

31 Jul 2018, 02:39

From what I've interpreted from photos the spark plug is centered in the CC ceiling, and the injector orifice is on the edge of the chamber approximately 40mm away, in between the exhaust ports. How then would the flame be ignited inside of a prechamber at such a distance? Autoignition? If all the fuel is inside the prechamber during a diesel moment then detonation wouldn't be an issue. The controlled explosion through the prechamber orifices would provide the turbulent jets to the CC. And then spark plug could go to town on the plasma, as you say. Furthering combustion of any unburnt fuel that survived the dieseling and jet expulsion.

If auto ignition occurs in the pre-chamber, the spark plug becomes redundant - at full load at least. I think this conflicts with the rules.

In the TJI concept the pre-chamber only gets 1% or 2% of total fuel. Its function is to ignite the main charge:
- rapidly at multiple locations
- at very lean AFRs where a spark-plug alone is inadequate.

If it really is a problem with the rules when you don't use the spark plug, they could just fire it for good measure afterwards.

Possibly imagining it, but there is an exhaust frequency I'm not particularly familiar with from the Honda PU.. it's sounding different here. Also missing that 2nd and 3rd grinding sound going into gears they've had year round. Update maybe?
Thoughts?

https://twitter.com/ToroRosso/status/10 ... 68000?s=09

GhostF1 wrote: ↑

31 Jul 2018, 14:49

Possibly imagining it, but there is an exhaust frequency I'm not particularly familiar with from the Honda PU.. it's sounding different here. Also missing that 2nd and 3rd grinding sound going into gears they've had year round. Update maybe?
Thoughts?

https://twitter.com/ToroRosso/status/10 ... 68000?s=09

Unbelievably, that sound reminds me of a sidevalve Back to the future?

Big Tea wrote: ↑

31 Jul 2018, 18:37

GhostF1 wrote: ↑

31 Jul 2018, 14:49

Possibly imagining it, but there is an exhaust frequency I'm not particularly familiar with from the Honda PU.. it's sounding different here. Also missing that 2nd and 3rd grinding sound going into gears they've had year round. Update maybe?
Thoughts?

https://twitter.com/ToroRosso/status/10 ... 68000?s=09

Unbelievably, that sound reminds me of a sidevalve Back to the future?

Who you callin' a sidevalve, flathead?

roon wrote: ↑

31 Jul 2018, 19:16

Big Tea wrote: ↑

31 Jul 2018, 18:37

GhostF1 wrote: ↑

31 Jul 2018, 14:49

Possibly imagining it, but there is an exhaust frequency I'm not particularly familiar with from the Honda PU.. it's sounding different here. Also missing that 2nd and 3rd grinding sound going into gears they've had year round. Update maybe?
Thoughts?

https://twitter.com/ToroRosso/status/10 ... 68000?s=09

Unbelievably, that sound reminds me of a sidevalve Back to the future?

Who you callin' a sidevalve, flathead?

https://twitter.com/ToroRosso/status/10 ... 6942504960

That sound.. Keeps on giving me goosebumps

We didn't complete any low fuel runs or qualifying simulations in order to concentrate on our aerodynamic development.

https://scuderiatororosso.redbull.com/e ... t-04-day-2

In other articles it was understood that Honda are trying to bring a quali mode in spec 3, however, after reading this, I'm not so sure as otherwise they might have had a go with it close to end of the session.

Question here - A lot has been discussed about how quali modes might work, including oil burning, but now that this has been clamped down, how do you think such a mode would work? Surely it must be some particular mapping that alters timing, AFR etc. and that goes beyond just 'turning on' the power and reducing reliability and PU life, otherwise surely both Honda and Renault would be doing it.

I apologise in advance - not too technical here - but I do understand some basic technical concepts.

Revs84 wrote: ↑

01 Aug 2018, 22:11

We didn't complete any low fuel runs or qualifying simulations in order to concentrate on our aerodynamic development.

https://scuderiatororosso.redbull.com/e ... t-04-day-2

In other articles it was understood that Honda are trying to bring a quali mode in spec 3, however, after reading this, I'm not so sure as otherwise they might have had a go with it close to end of the session.

Question here - A lot has been discussed about how quali modes might work, including oil burning, but now that this has been clamped down, how do you think such a mode would work? Surely it must be some particular mapping that alters timing, AFR etc. and that goes beyond just 'turning on' the power and reducing reliability and PU life, otherwise surely both Honda and Renault would be doing it.

I apologise in advance - not too technical here - but I do understand some basic technical concepts.

They have said they managed to test a lot of new components and did plenty of mapping work over the test, so it's still possible they were testing how the PU responds in a certain mode, that does not necessarily mean running a full quali sim while doing that.

I'm fairly certain, based on previous articles from Honda, that a quali mode is all about managing knock in order to utilise the higher power mode for a short time. For that to be mentioned, I think the power comes from a leaner burn mode and all that comes with that. If it was from a short time electrical motor mode, I'm not certain knock would be the biggest issue.

But then again.. Honda said the Spec 3 would be focusing on a new MGU-K and energy systems. So maybe there's something to that.

Obviously this is all speculatory.

Oil burning has almost been clamped out by reg and may only bring about few hp at top end of peak power. I didnt believe it but now i bow to the superior wisdom of Wazari, who mentioned sometime back that quali modes are mostly down to ERS, obviously ICE will be on full whack. Just look at Ferrari power cars, they got upper hand on Merc in quali yet engine output is about similar. Based on plum faces at Merc i think they believe they cant extract much more from ICE so now are desperate to understand Ferraris trick.

Electric supercharger mode should not be underestimated. Reducing exhaust back pressure by 2.5 bar will increase output by up to 35 kW. The electrical cost is perhaps 65 kW.

Beyond this, increasing the boost from 3.5 bar abs to 4.5 will further increase output (via positive intake pumping work) by up to 14 kW although at an additional electrical cost of perhaps 45 kW.

gruntguru wrote: ↑

02 Aug 2018, 00:53

Electric supercharger mode should not be underestimated. Reducing exhaust back pressure by 2.5 bar will increase output by up to 35 kW. The electrical cost is perhaps 65 kW.

Beyond this, increasing the boost from 3.5 bar abs to 4.5 will further increase output (via positive intake pumping work) by up to 14 kW although at an additional electrical cost of perhaps 45 kW.

Any reason to stop at 4.5?

Not sure they even go that far.
The downsides are:
- High MGUH load and ES drain for little power increase
- Increasing AFR and probable loss of combustion efficiency and crankshaft power

They may for qualifying, ES storage is an issue of course, but you can go back to the oversized/overspun turbo and wind it up the lap before.

gruntguru wrote: ↑

02 Aug 2018, 02:01

- Increasing AFR and probable loss of combustion efficiency and crankshaft power

Ideally they maximize piston power while maximizing airflow to the turbine. Seems like that would be a good development target considering how the formula is structured. If we assume, via techniques, combustion is optimized regardless of AFRs, would it be correct to say: the challenge becomes heating the air within the piston sufficiently and quickly.

Pushing the pistons with the compressor is inefficient but H deploy and battery charge rates are the only big areas left to develop on the hybrid systems. The next dev goal would then be exhausting ~4MJ through the H on each long straight (several hundred MGUH HP, plus fractional amounts of the 4MJ/lap K-deploy), and regenerating 4MJ via K and H in between such deploys. Roughly speaking.

Edit: added section in italics.

roon wrote: ↑

02 Aug 2018, 05:39

gruntguru wrote: ↑

02 Aug 2018, 02:01

- Increasing AFR and probable loss of combustion efficiency and crankshaft power

Pushing the pistons with the compressor is inefficient but H deploy and battery charge rates are the only big areas left to develop on the hybrid systems. The next dev goal would then be exhausting 4MJ through the H on each long straight (several hundred MGUH HP), and regenerating 4MJ via K and H in between such deploys. Roughly speaking.

There is actually no point in designing the MGU-H for much more than 120kW. In normal race mode, the MGU-H starts to harvest energy down the straights as soon as the desired boost pressure is reached and that happens pretty quick. So as soon as the MGU-H can deliver 120kW, you go with that power directly to the MGU-K. First of all it's more efficient, because you don't have to face the conversion loses the battery system has, secondly there is no need to draw Energy from the battery by the MGU-K. It works at full power already.
The only problem would be the transition period out of the corner when the MGU-H can't deliver the 120kW to the MGU-K. But there's a good chance that the up to 2MJ of energy per lap harvested by the MGU-K under braking is enough to bring the system through this transition period or design the MGU-H slitghly more powerfull, maybe 150kW. But there is absolutly no need to design the whole thing for several hundred hp, would just make the whole thing unnecessary heavy.