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Fully digital valves open up engine possibilities

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Re: Fully digital valves open up engine possibilities

#21

Post by yontherubicon »

thinkingkong wrote: post #6
tomatotomato37 wrote: post #3

I thought koenigsegg was already doing this with their freevalve thing Also I saw an interesting point in an article about the koenigsegg thing that would pertain to this too; environmental laws would be much harder to practically enforce with this as you could run virtually any engine anemic enough to get though the emissions tests (and set it as the default mode to get around the Volkswagen nonsense) and then offer…

Wouldnt the test just need to apply to all modes? If its a matter of automatically tuning through a series of conditions then its reasonable that those could be documented and tested by the facility / standards body.

Sure, but emissions testing after you've got the car would be utterly useless.

Re: Fully digital valves open up engine possibilities

#22

Post by maxxxxx »

hevi_jos wrote: post #15
ak217 wrote: post #11

Earlier quoted context omitted.

> The simplicity advantage of electric will soon take a quantum leap when driveshaft-free 4 motor all wheel drive vehicles hit the market You can't just eliminate the driveshaft because the wheel must be on a suspension. Remove the driveshaft and you have to put the motor on the wheel, increasing unsprung weight, exposing the motor and making high voltage parts subject to damage. 4 motors is more complex than 2 and d…

4 electric motors on wheels is extremely simpler than 2 motors, mechanical differentials and couplings. I actually helped a mechanical engineer to create a simulator for car dynamics in software. Today's cars are over engineered mechanically in order to support and resist the forces and torques from the motor to the wheels. When you put the motors in wheel you basically reduce the required rigidity and the weight of…

" 4 electric motors on wheels is extremely simpler than 2 motors, mechanical differentials and couplings."

Why not 2 on one axle? Do you really need all wheel drive?

Re: Fully digital valves open up engine possibilities

#23

Post by TheSpiceIsLife »

tomatotomato37 wrote: post #3

I thought koenigsegg was already doing this with their freevalve thing Also I saw an interesting point in an article about the koenigsegg thing that would pertain to this too; environmental laws would be much harder to practically enforce with this as you could run virtually any engine anemic enough to get though the emissions tests (and set it as the default mode to get around the Volkswagen nonsense) and then offer…

> environmental laws would be much harder to practically enforce ... and then offer high/sport/cruise modes that runs the engine at full capacity otherwise

Only if your company is ready to willfully break the law.

The vehicle ought to, at the time of testing, meet or exceed all relevant standards, and not have a user accessible option to circumvent the standards.

Re: Fully digital valves open up engine possibilities

#24

Post by perilunar »

mkstowegnv wrote: post #7
rmason wrote: post #2

It seems in tech just when the incumbents seem like they will lose to the upstart they achieve a breakthrough and the inevitable is delayed for a few more years. Combine this breakthrough with what Michigan State is doing in gas powered engines and battery powered cars dominance is delayed for at least another decade. http://www.wkar.org/post/reworking-michigan-msu-develops-lig...

The inherently self destructive nature of ICE's make it likely that ICE vehicles will always be more complex, less reliable/ higher maintenance than comparable all electric vehicles. The simplicity advantage of electric will soon take a quantum leap when driveshaft-free 4 motor all wheel drive vehicles hit the market [1]. On the other hand as long as batteries are heavy, ICE's will have a place in aircraft, and I wou…

> On the other hand as long as batteries are heavy, ICE's will have a place in aircraft, and I would think the OP's technology could be huge for helicopters.

The future of ICEs for aircraft is turbines, not piston engines with digital valves. Most commercial aircraft are already turbines; the only thing holding them back for light aircraft is cost.

Re: Fully digital valves open up engine possibilities

#25

Post by taneq »

jondumbau wrote: post #14

Nitpicky, but compression release for easy (easier..) starting is already a thing. It talks about completely opening the valves so the starter only overcomes friction. Presumably they're talking about having the cylinders that aren't yet fired spinning over freely? Otherwise it's a very efficient way to spin and engine that can't possibly start without "compressing gasses".

I guess it'd lower the starting torque which might let them use a smaller starter motor? You'd spin the engine for a couple of revolutions, then use the stored kinetic energy to kick start the engine.

Re: Fully digital valves open up engine possibilities

#26

Post by Fjolsvith »

jondumbau wrote: post #13
jondumbau wrote: post #12

The temporary 2 stroke idea doesn't sound very well cooked. Fine control over the valves is great, but the exhaust and other aspects of the engine need to be tuned for that use case.

Also the "2 strokes are the future" remark seems a bit off too. The future of enduro bikes and chainsaws maybe.

Yeah, this idea is just in time for the all-electric revolution.

Re: Fully digital valves open up engine possibilities

#27

Post by King-Aaron »

Fjolsvith wrote: post #26
jondumbau wrote: post #13

Earlier quoted context omitted.

Also the "2 strokes are the future" remark seems a bit off too. The future of enduro bikes and chainsaws maybe.

Yeah, this idea is just in time for the all-electric revolution.

The "all-electric' revolution you've got in mind is likely much further away than you expect. There will be a market for internal combustion engines for many more decades before all-electric vehicles can replace the markets in areas that are more remote, or require long hauling vehicles etc.

Re: Fully digital valves open up engine possibilities

#28

Post by jondumbau »

King-Aaron wrote: post #27
Fjolsvith wrote: post #26

Earlier quoted context omitted.

Yeah, this idea is just in time for the all-electric revolution.

The "all-electric' revolution you've got in mind is likely much further away than you expect. There will be a market for internal combustion engines for many more decades before all-electric vehicles can replace the markets in areas that are more remote, or require long hauling vehicles etc.

agree. but you can barely get a 2 stroke passed the existing emission laws, and they're not generally in use in motor racing outside of enduro. ¯\(°_o)/¯

Re: Fully digital valves open up engine possibilities

#29

Post by jondumbau »

TheSpiceIsLife wrote: post #19
jondumbau wrote: post #14

Nitpicky, but compression release for easy (easier..) starting is already a thing. It talks about completely opening the valves so the starter only overcomes friction. Presumably they're talking about having the cylinders that aren't yet fired spinning over freely? Otherwise it's a very efficient way to spin and engine that can't possibly start without "compressing gasses".

Exhaust valves are open during the exhaust stroke anyway. Inlet valves are open during the intake stroke anyway. The strongest plausible interpretation of what ¹ they're saying is to open valves that are partway through the compression stroke, and open / close any other valves as necessary at the best possible time to promote rapid starting. 1. https://news.ycombinator.com/newsguidelines.html

that really makes the most sense. at that point i imagine it would be a more finely controlled compression release. i shouldn't read too much into the wording of what is essentially a marketing statement i suppose :)

Re: Fully digital valves open up engine possibilities

#30

Post by ebikelaw »

This article is pretty much wall-to-wall snake oil. The bit at the end is just completely false. Some people, who hadn't really bothered to do the math at the time, believed fifty years ago that spring-closed valves would float at high speeds and desmodromic valves were the solution. But that isn't true: metallurgy marches on, and nobody has been seriously impeded in making an engine turn at any desired speed with valve springs. Motorcycle engines turn at stupefying speeds without experiencing valve float. In practice it's actually the desmodromic designs that are troublesome, because of all that moving mass.

Anyway, there are lots of other dumb claims in here, like nobody has ever done variable timing of exhaust valves, which is obviously not true.

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