2021 Engine thread

[wuzak]

I did not claim it was the sole cooling method/system..
..but actually, it does offer significant extra cooling*, internally.. via 'latent heat' effects..

..just as the BMW 801 engine which featured DI.. some decades ago..
also derived cooling benefit from extra fuel added similarly by aux' injection upstream ( to the air intake)..

..as needed.. ..to stave off 'heat-soak' induced power fade/melt-down - when running real hard..

This method is, of course, also specifically excluded from F1 by the current tech regs..

* If you have access to a (carb equipped) 2T powered road vehicle which has a temp gauge,
you can do an empirical test which demonstrates this..
..run it up to SOP temp, find a long downhill slope, & flick the ignition 'kill switch',& hold it WFO,
.. then by rolling it downhill, while still in gear, you can see the temp rapidly drop - in real time...

Ok, so you've turned the engine off, and are pumping air and fuel through the engine while still getting some cooling effect from the cooling system and you think it's the fuel that is cooling the engine?

You responded to a post from roon asking the question of whether it would be possible to eliminate the cooling system. To which the answer is no.

And the BMW injection system was a form of ADI.

[63l8qrrfy6]

Forgive me for being daft, but isn't the point of having steel pistons to reduce heat transfer from the combustion chamber to the crankcase, via oil?

The reason for choosing steel is that it can cope with higher temperatures than aluminium.

Honeycomb structures beneath the crown could serve to reduced heat transfer, especially if they are enclosed.

The idea being that the more heat kept inside the combustion chamber the better. This would also be achieved with as high a coolant temperature as possible.

The more heat retained in the chamber the more power to drive the engine. Higher coolant temperatures increase transfer rates in radiators, reducing the size of those. Less heat transfer between combustion chamber and coolant also means smaller radiators.

Similarly, the less heat transfer through the piston the smaller the amount of cooling oil required. Which means a smaller oil cooler. And less power to drive the oil pump. Which means better aero and more power at the crank.

Ughh big mistake here - rate of heat transfer and delta T are not the same thing. T2 (after the radiator) will increase if T1 increases.

The stresses in the steel piston are a few times higher than in Al as discussed earlier. Even if steel has better endurance strength it still does not allow it to run much hotter. As steel's thermal conductivity is lower I reckon you still need about the same oil mass flow to the under crown as for Al to prevent the strength from dropping.

One other thing to consider is that the maximum heat transfer coefficient to the cylinder head occurs when the coolant undergoes nucleate boiling. The window for this is fairly narrow and any significant increase in combustion temperature can shift the coolant into full blown boiling, causing the HTC to drop off drastically.

Lastly, I really do hope you realized that my post about wearing puffy jackets in the summer was a joke.

[wuzak]

Lastly, I really do hope you realized that my post about wearing puffy jackets in the summer was a joke.

Sometimes hard to tell with the written word.

[J.A.W.]

I did not claim it was the sole cooling method/system..
..but actually, it does offer significant extra cooling*, internally.. via 'latent heat' effects..

..just as the BMW 801 engine which featured DI.. some decades ago..
also derived cooling benefit from extra fuel added similarly by aux' injection upstream ( to the air intake)..

..as needed.. ..to stave off 'heat-soak' induced power fade/melt-down - when running real hard..

This method is, of course, also specifically excluded from F1 by the current tech regs..

* If you have access to a (carb equipped) 2T powered road vehicle which has a temp gauge,
you can do an empirical test which demonstrates this..
..run it up to SOP temp, find a long downhill slope, & flick the ignition 'kill switch',& hold it WFO,
.. then by rolling it downhill, while still in gear, you can see the temp rapidly drop - in real time...

Ok, so you've turned the engine off, and are pumping air and fuel through the engine while still getting some cooling effect from the cooling system and you think it's the fuel that is cooling the engine?

You responded to a post from roon asking the question of whether it would be possible to eliminate the cooling system. To which the answer is no.

And the BMW injection system was a form of ADI.

Yes, wuzak, notwithstanding your apparent misrepresentation of my response to another members post..
I do concur, even given the promise of high temp ceramics, or not..
so..
"the answer is no"...
But never-the-less, (& yet again it seems, I must reiterate) - I did not make any claim whatsoever about..
"...whether it would be possible to eliminate the cooling system"..

However, with regard to the internal cooling via 'latent heat' - then yes, of course...
..since its a simple thing to run downhill, ignition off with closed throttle..
& thus clearly note the temp indication moves much less than it does when held WFO..

I have no doubt that the extra TBI set-up fitted to the most recent Rotax/BRP Ski-Doo 850 functions
in a manner analogous to the earlier BMW set-up, as both ADI safety & WFO cooling stability control..
..as well as fundamentally maintaining power output by preventing fade due to heat-soak, as stated..

It is a noted* fact that recent DI 2Ts have had to have revised coolant circulation patterns due to
the effects of the 'latent heat' cooling effect lost - by not running fuel through the crankcase...

*Noted by Kevin Cameron, on his blog..

[roon]

Is nitrogen (with a small carbon dioxide content) an ideal working fluid for an oxygen-breathing ICE? Would argon, or helium, or xenon(?), or another inert gas, provide any benefits? Gases which might absorb combustion heat differently, or provide work to the piston differently. Heavier gases would have different flow properties. A helium engine would have a high pitched "zing!" Ha ha. There you go, we can have that high-pitch V10 sound again with our lawn mower engines.

Or some basso profundo thunder if sulfur hexaflouride is used.

If the car were to have compressed gas tanks along with the fuel tank, it could do away with traditional intake & coolant systems. The expansion of the pre-cooled but not-necessarily cryogenic working gas, either in-cylinder or through external jackets, would provide cooling. A smaller oxidizer tank would provide the... oxidizer. Range would be limited as evidenced by compressed air powered cars, so perhaps a lot of pit stops would be needed between sprints.

Point of all this would be: no HXs and combustion cycle benefits, if any. The marketing pitch could be about the need to develop engine technology for use in environments without terran atmospheres, in preparation for exploration of the solar system.

F1 could take a sci-fi direction in 2021 instead of a backwards-looking "durr... sound" approach advocated by the head-wall banging crowd. They can be placated by earplug-shaped firecrackers offered in the stands. "Earbreakers here! Get yer fresh earbreakers!"

One final point: if gas injectors replace intake valves, and different gas properties are taken advantage of, perhaps ideal combustion chamber shapes could be formed within the working fluid. If a heavy gas fills the cylinder, a bubble of oxygen or oxygen rich gas could be blown in the center of the chamber, along with fuel within it. The surrounding jacket of working gas would compress and work the piston as the spherical combustion bubble expands. The flame front & combustion products could be isolated from contact with any metallic surfaces. Perhaps even a recirculating liquid could be used as the working medium in this context, instead of a gas, and recuperated in the exhaust system.

A liquid, being less compressible than a gas, would act as an intermediary between the combustion gases and the solid reciprocating mechanical components, providing a shape-shifting layer that contains the combustion event while transferring work to the piston. A hydraulic internal combustion engine. With the goal again being: elimination of a traditional cooling system & exploration of combustion benefits, if any.

If the liquid or heavy-gas had insulative properties, then all the better, we can perhaps achieve something like the hard-to-realize dream of a ceramic engine in terms of heat-retention while still using traditional materials. The working medium might also be foamed or imbued with nano/micro ceramic particles to alter its insulative effects.

[gruntguru]

So if they made the mixture rich enough - say 15:1 you would only need to carry about 1500kg of compressed gas on board. You could be on to something!

[roon]

I mentioned the range issue in the context of a consumable stored working fluid. Was there a specific point you were trying to make?

[J.A.W.]

I mentioned the range issue in the context of a consumable stored working fluid. Was there a specific point you were trying to make?

It has been tried, & for sure, it was a spectacle, but perhaps a bit too fraught for passing attempts..

[NL_Fer]

The longer i think about it, the more certain i am that the hyperefficient leanburn combustion engine is a dead end. Maybe Wartsila or MHI are interested, but it is not going to be important for cars. So i really believe the next engine should be a simple twin-turbo direct injection engine, no flow limit, just limit on boost and rpm.

And to keep the "hybrid" part a KERS system with front axle recovery. F1 has to be RWD and not to heavy.

[roon]

One single cylinder engine, transmission & driveshaft per wheel. Fine control of engine speed may be necessary to keep the car moving in a straight line. Perhaps shafts and clutches or torque converters linking each engine to the other could assist in bringing adjacent engines up or down to a req'd speed.

As the four engines fall in and out if sync with each other, the composite exhaust note will be ever changing. At some points people will say "Oh, that sounds amazing," and at other times people will say "Oh, that sounds terrible, I am offended."

Thus, we have the consensus drivetrain, which aims to produce a sound that satisfies everyone at least part of the time.

The longer i think about it, the more certain i am that the hyperefficient leanburn combustion engine is a dead end. Maybe Wartsila or MHI are interested, but it is not going to be important for cars.

Why do you think this?

[AJI]

One single cylinder engine, transmission & driveshaft per wheel...

This may just level the playing field. Honda and Renault are apparently excellent at the single cylinder versions of their PU's.
If you make them an in-wheel design you get a PU change and refuelling at every pit stop!

[gruntguru]

The longer i think about it, the more certain i am that the hyperefficient leanburn combustion engine is a dead end. Maybe Wartsila or MHI are interested, but it is not going to be important for cars.

Why?

[ESPImperium]

My solution for the 2021 engine would be as follows:

- Keep the present V6 ICE, its a great wee unit and is well developed by then. Allow development of the ICE up until 2025 then have it fully frozen
- Place twin Turbos or Superchargers on the engine, manufacturers will be free to choose what they wish to use.
- Up the MGU-K to a 8mJ system, with the car being able to run up to 60 seconds a lap on full power.
- Standardised Control Electronics and Energy Store
- Each area of the engine is limited to 4 units per season, new manufacturers will be exempt from penalties for a period of two years (unless they score three victories in first season) and manufacturers who have no win in last 5 seasons will also be exempt, Manufacturers with no victories in past 3 seasons will be granted 6 of each unit per season.
- Fuel will be strictly limited to 250 litres per car for the weekend, of which each supplier will only be allowed 4 fuel mixes per season
- Gearboxes will be brought back to a 7 speed and have to last for 5 races. However with standardised Gearbox internals, however the gear ratios can be chosen for each gearbox for tailoring of ratios for each driver. The final gear can be changed at each event as well. Main gear ratios will be from a pool of 50 available with 10 available final ratios. Ratios chosen for each gearbox to be submitted and publicly shown, final drive ratio changes also shown publicly.
- Standardised electronics, new generation of SECU will have to have the manufacturer source code inputted into its micro-code so the standardised rotary that operates engine power to fuel efficiency can work, so all teams have access to full power, no works bias.
- Steering wheels to be simplified to 7 rotaries and a maximum of 14 buttons/switches
- Engine pool at factory side to be chosen at random, no manufacturer cherry picking in order to ensure that fairness is shown.

With this engines would be able to reach a easy 1,000plus BHP and be cost effective enough for a small team to spend €25m on a full supply of a rear end for the season. Id also make it that before each session the component number must be publicly shown via FIA web site for transparency.

Manufacturers of engines only (Honda) can supply a maximum of 5 teams, Manufacturers who have a works chassis side (Mercedes, Ferrari, Honda) can only supply two customer teams a season. In present terms, the manufacturers would be fine, but add a 11th and 12th entry and things would complicate as they would be locked into Honda or another supplier, or Ferrari once Sauber switch to Honda.

[CriXus]

I am not a tech expert at all, but the most sensible thing is to allow free choice of engine displacement and number of cylinders, because every engine manufacture has its own preference, the twin turbo and MGU-K are mandatory. The power will be controlled through the turbo boost and RPMs.

[NL_Fer]

The longer i think about it, the more certain i am that the hyperefficient leanburn combustion engine is a dead end. Maybe Wartsila or MHI are interested, but it is not going to be important for cars.

Why?

Because i feel, that hi-end commuter cars will be full electrics within 10 years. Combustion engines will be kept simple for basic cars or range extenders. Manufacturers will want to focus on electric drivelines by then and lose interest in development and marketing of combustion engines.