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Vigo
Vigo MegaDork
3/5/20 2:42 p.m.

The perks of a customer base that doesn't ask about price. 

Yeah, traditionally high-dollar research and eventual commercialization of new technology is done through defense spending and the customer base that doesn't ask about price is all the taxpayers unknowningly paying for it. Compared to that, i think Koenigsegg kinda takes the hard road. 

STM317
STM317 UltraDork
3/5/20 2:58 p.m.
Vigo said:

The air pump is the thing that looks like an ac compressor (belt driven). It has a large air line going up to the front of the cylinder head where you see it split to each side and you have big connectors for the solenoids on each side. One thing to note is that it's getting its air feed from the intake manifold which means that any time you're in boost the compressor is fed pressurized air and acting as a '2nd stage'.

I don't see it getting air from the intake manifold. It looks to me like the solid pipe that runs from the compressor towards the intake manifold actually runs along the block, and up to the back of the cylinder head. It mates to the cylinder head with a single cast elbow, while the "Y" that you pointed out up front mates higher on the engine, to what I guess would be the valve cover. So it seems like that pump supplies something to one side of the cylinder head, it passes through the head, and then returns to the pump. The fact that one side of the loop is lower on the head could mean that it's partially drained by gravity which seems unusual if it's just air.

sobe_death
sobe_death Dork
3/5/20 3:46 p.m.
STM317 said:
Vigo said:

The air pump is the thing that looks like an ac compressor (belt driven). It has a large air line going up to the front of the cylinder head where you see it split to each side and you have big connectors for the solenoids on each side. One thing to note is that it's getting its air feed from the intake manifold which means that any time you're in boost the compressor is fed pressurized air and acting as a '2nd stage'.

I don't see it getting air from the intake manifold. It looks to me like the solid pipe that runs from the compressor towards the intake manifold actually runs along the block, and up to the back of the cylinder head. It mates to the cylinder head with a single cast elbow, while the "Y" that you pointed out up front mates higher on the engine, to what I guess would be the valve cover. So it seems like that pump supplies something to one side of the cylinder head, it passes through the head, and then returns to the pump. The fact that one side of the loop is lower on the head could mean that it's partially drained by gravity which seems unusual if it's just air.

It's quite possible that the bleed air for valve actuation goes to a common manifold, back to pump inlet.  Using the manifold boost along with the bleed manifold would be a very nice way to keep the pressure ratio lower on the engine-driven pump. Then again, maybe the whole system is lubricated with PAG oil circulated by the compressor...

alfadriver
alfadriver MegaDork
3/5/20 5:11 p.m.
STM317 said:
Vigo said:

The air pump is the thing that looks like an ac compressor (belt driven). It has a large air line going up to the front of the cylinder head where you see it split to each side and you have big connectors for the solenoids on each side. One thing to note is that it's getting its air feed from the intake manifold which means that any time you're in boost the compressor is fed pressurized air and acting as a '2nd stage'.

I don't see it getting air from the intake manifold. It looks to me like the solid pipe that runs from the compressor towards the intake manifold actually runs along the block, and up to the back of the cylinder head. It mates to the cylinder head with a single cast elbow, while the "Y" that you pointed out up front mates higher on the engine, to what I guess would be the valve cover. So it seems like that pump supplies something to one side of the cylinder head, it passes through the head, and then returns to the pump. The fact that one side of the loop is lower on the head could mean that it's partially drained by gravity which seems unusual if it's just air.

I didn't look close, but it would make sense to me- not because of the boosted intake, but because it's filtered air.  Which I'm sure goes through another one before becoming the spring.

This is interesting tech, but don't see it getting out of their cars anytime soon.  For sure, it won't be in large serial production before I retire.

STM317
STM317 UltraDork
3/5/20 7:15 p.m.

In reply to alfadriver :

The compressor or pump and associated lines that we're talking about look like a closed loop system to me, akin to the refrigerant in an AC system, but the pics aren't perfectly clear. The shapes, diameter, and connections used on the cast parts and hard tubing just look like they're designed for something other than air to me. And I haven't seen braided line used for air before either. But there's never been a vehicle like this before, so we'll have to wait and maybe it will be revealed one day.

 

As for commercial viability, I'd guess that you may be right, but they were reporting strong results in extensive field tests with a Chinese manufacturer a couple of years ago: https://www.sae.org/news/2017/09/camless-engine-evaluation-nearly-complete-in-china

GIRTHQUAKE
GIRTHQUAKE HalfDork
3/5/20 7:31 p.m.

It's also possible it's not using atmospheric air at all- looking at the pictures, it seems entirely closed-loop. If that's the case, I wonder if it could be an oil too?

I also noticed that he's removed the side mirrors for cameras.

In reply to STM317 :

Ah, makes sense that they would share parts like that. I wonder if this system also has some kind of dampener? I remember reading somewhere that an I-3 has some serious low-end vibrations.

In Reply to Vigo :

Also worth noting that Christian has been VERY open in that he really just builds and designs whatever interests him and the people he employs- supercars get plenty similar quick since so many are fighting for tenths over their competition, and Christian has always been kind of a genius engineer so I feel like this is more of an experiment to mix supercar ability with SOME practicality in mileage and seating for 4. Especially when you consider how (I think) they're the first OEM whom twin-supercharged an engine or the whole replacement for a standard transmission in the One:1 project.

GIRTHQUAKE
GIRTHQUAKE HalfDork
3/5/20 7:38 p.m.

Something else I note in the description:

... Combined with electrification, the Gemera can be argued to be cleaner than a long-range EV, by using next-generation combustion technology designed for next-generation renewable liquid fuels, together with a small battery plug-in electrification.

The Gemera, if plugged in and filled with Gen 2.0 ethanol or CO2 neutral methanol like Vulcanol or any mix thereof, becomes at least as CO2 neutral as a pure electric car. Before these second-generation renewable fuel sources are more accessible, the Gemera can also be driven on E85 and in worst case normal petrol.

So it's meant to run synthetic fuels? I haven't really heard about serious new ones since Tesla has become so eponymous with "green" technologies (and also since hydrogen hasn't done much).

NorseDave
NorseDave Reader
3/5/20 10:03 p.m.
Vigo said:

The perks of a customer base that doesn't ask about price. 

Yeah, traditionally high-dollar research and eventual commercialization of new technology is done through defense spending and the customer base that doesn't ask about price is all the taxpayers unknowningly paying for it. Compared to that, i think Koenigsegg kinda takes the hard road. 

As someone who has spent much of my early engineering career working in said defense industry, I can't thumbs-up this analysis enough.  Unfortunately.   

infinitenexus
infinitenexus Reader
3/6/20 6:20 a.m.

From the koenigsegg page on the engine:

 

The TFG has an estimated fuel consumption of 15 – 20% less than a typical modern four-cylinder two-liter engine with direct injection and variable camshaft.

The Freevalves improve engine efficiency at part load by eliminating throttle losses since there is no throttle.

Furthermore, Freevalves deactivates cylinders with Frequency Modulated Torque to further reduce fuel consumption.

Freevalves are also capable of running the so-called Miller cycle, which is why the TFG can have a static compression of 9.5:1, which is high for a high boost turbo engine. Using the Freevalve system to run for example the Miller cycle, gives the TFG high efficiency and high power at the same time. All factors considered, the TFG is one of the most frugal and most powerful production engines in the world for its size.

 

The more you read, the more fascinating it gets.

https://www.koenigsegg.com/gemera/tiny-friendly-giant-engine/

alfadriver
alfadriver MegaDork
3/6/20 6:57 a.m.

In reply to STM317 :

WRT the commercial viability- you'll note I mentioned "before I retire"- which is a (pretty happy) way of pointing out that the prediction is pretty short term.  laugh

And noting the amount of SAE literature coming out plus what suppliers are bringing us stuff for that should be production ready if the development time starts today, I'm close to 100% sure that by the time I retire, it's not going to be offered in a car that normal people can afford.

The idea has been a real dream once computers got powerful enough to actually be able to deal with them- which happened about 20 years ago, and I knew people who were working on it back them (and it kind of gives ma a sad, as a good friend did work on that, and he died of cancer over 10 years ago... ).  The BMW system offers quite a few of the benefits vs. normal VCT systems for a lot less money and complexity- and given what Fiat put out, more developments of that style will emerge well before the system is capable for high production.  And by then, there's a really good chance the battery quantum leap will have happened, which would render the benefits rahter moot.

alfadriver
alfadriver MegaDork
3/6/20 7:02 a.m.
infinitenexus said:

 

The Freevalves improve engine efficiency at part load by eliminating throttle losses since there is no throttle.

 

I wish people would stop claiming that- it's partially BS.  Gas engines are throttled via control of the air flow- be it from throttling a manifold that all of the chambers pull from OR making the cam timing so that not all of the airflow ends up in the engine.  Either way, the chamber is going to partially pull on a vacuum- as just pumping the air back into the intake is also work....

Sure, it eliminates the losses due to pulling the air across a throttle plate, but it does not eliminate the losses due to pumping a vacuum, which ends up being the same physics.  Otherwise, there's no air flow control, and no power control.

Knurled.
Knurled. GRM+ Memberand MegaDork
3/6/20 7:03 a.m.

In reply to alfadriver :

What if they were "throttling" the engine with Miller/Atkinson Cycle tactics?

alfadriver
alfadriver MegaDork
3/6/20 7:58 a.m.

In reply to Knurled. :

It's still the same effect- just a little less.  There's no "elimination" of pumping losses- there's always going to be some kind of loss when you only want x% of the air pressure relative to volume to combust with.

The only throttling that has the potential of eliminating pumping losses in a positive manner (spark is a terrible throttle relative to efficiency) is fuel.  Which, at the end of the day, becomes a diesel engine.  Throttling the otto cycle really means giving up efficiency due to pumping, somehow.

ProDarwin
ProDarwin UltimaDork
3/6/20 8:07 a.m.
alfadriver said:

In reply to Knurled. :

It's still the same effect- just a little less.  There's no "elimination" of pumping losses- there's always going to be some kind of loss when you only want x% of the air pressure relative to volume to combust with.

The only throttling that has the potential of eliminating pumping losses in a positive manner (spark is a terrible throttle relative to efficiency) is fuel.  Which, at the end of the day, becomes a diesel engine.  Throttling the otto cycle really means giving up efficiency due to pumping, somehow.

You can "throttle" via air density, but only so much.  A lot of the ecomodders make hot-air intakes for this reason.  Allows them to run a higher throttle opening for the same output power.

alfadriver
alfadriver MegaDork
3/6/20 9:06 a.m.

In reply to ProDarwin :

EGR does that a very effectively, and controllably.    

Still, to throttle the engine, you have to give up something in terms of efficiency- nothing is free.  Throttling losses, compression efficiency, combustion efficiency, etc- to make an Otto cycle throttle, something in the ideal function has to be given up, somewhere. 

Knurled.
Knurled. GRM+ Memberand MegaDork
3/6/20 9:17 a.m.
ProDarwin said:
alfadriver said:

In reply to Knurled. :

It's still the same effect- just a little less.  There's no "elimination" of pumping losses- there's always going to be some kind of loss when you only want x% of the air pressure relative to volume to combust with.

The only throttling that has the potential of eliminating pumping losses in a positive manner (spark is a terrible throttle relative to efficiency) is fuel.  Which, at the end of the day, becomes a diesel engine.  Throttling the otto cycle really means giving up efficiency due to pumping, somehow.

You can "throttle" via air density, but only so much.  A lot of the ecomodders make hot-air intakes for this reason.  Allows them to run a higher throttle opening for the same output power.

The ghost of Smokey Yunick nods in approval.

 

IIRC his "Hot Air" engine was supposed to run at intake air temps in the 400F range.  It's kind of a shame that he didn't like electronic engine controls, that had the potential to be interesting in the 1980s.

GIRTHQUAKE
GIRTHQUAKE HalfDork
3/6/20 9:19 a.m.
Knurled. said:

In reply to alfadriver :

What if they were "throttling" the engine with Miller/Atkinson Cycle tactics?

I don't know if you can run the Atkinson cycle on a turbocharger tho; I remember with the Mazda Milenia there's something about it's supercharger where it's real use was consistent pressurized airflow.

alfadriver said:

And by then, there's a really good chance the battery quantum leap will have happened, which would render the benefits rahter moot.

Agreed. Lithium-sulfur have begun to hit the market now, and they've got some serious advantages over standard lithium-ion- and that's not even getting to the possible potassium chemistries OR Goodenough's "glass batteries".

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