ESE's works engine tuner

[Lightbulb]

A few pages back Frits implied, though did not flat out state, that if we looked in the exhaust port and ran the piston from top to bottom we wouldn't see anything unusual. I think we would see some of what you described above looking in the exhaust port and that would be unusual.

No, looking from the cylinder top down at the bore, you would see regular ports.Likewise looking through the exhaust port, all will look normal. Even taking the carb off, all you will see is the 1st of what I think are actually 3 sets of reeds. Frits has been very kind and told us all way more than he should have really. Think of an upside down Dunelt piston but a bit changed of course. The picture with the superimposed piston needs a small piston diameter through the plate,maybe 30mm diameter, and like a tapered top hat above the plate. Then you just need reeds for the induction to fill the pressure chamber, and reeds to control the out flow to the ports at the right time-these will be in the spacer plate. I think it is these last reeds that are preset to x amount of pressure, that finally mix the fuel to a fog and allow HCCI to become a reality. The main reed block allows the max flow into the pre chamber area, and will I guess stop any negative pipe pressure pulses arriving at the carb, another big plus. It is very possible that a big enough negative pulse could still draw mixture fog through the entire system and into the cylinder but with no pulse back into the carb to disrupt the continual flow.
Neil

[mr bucketracer]

Frits,
Just a simple naïve question. Would the Ryger technology be applicable to a 4 stroke engine?

just a engine from china

[Frits Overmars]

... the assumption, that detonation would be "pressure ignition" caused by violent shock waves..

It's the other way around: shock waves are the result rather than the cause of detonation.

let´s say that compression ratio=pressure of the non ignited charge at TDC.

Let's not say that. A ratio and a pressure are totally different notions. A compression ratio is the ratio between two volumes. Even if those volumes are completely vacuum, it won't change the ratio.

I almost hope that Frits wouldn´t say anything.

Sorry Tunisti .

Frits, Just a simple naïve question. Would the Ryger technology be applicable to a 4 stroke engine?

The mechanical part of it: yes. The thermodynamics part: yes. The gas dynamics part: no.
Get well soon, Ken .

[ken seeber]

The mechanical part of it: yes. The thermodynamics part: yes. The gas dynamics part: no.
Get well soon, Ken .

Frits, thanks for the answer and also your concern re my health.
I do like the answer and, not that I was feeling crook, but I do feel a lot, lot better knowing the answer. It tells us a lot.

[teriks]

Off topic but interesting project non the less, old Volvo Amazon with OMC 4 litre two-stroke V8. Will have to see some drag-racing when that thing is finished.

https://www.youtube.com/watch?v=RoiWpJLokEc

[AndreasL]

You bet me to that post teriks.

It's two friends of mine that is building the car.
Totally insane and a lot of high class craftsmanship.

The biggest concern right now is to sort the drive train.
CVT, auto or manual is the question. Know they have concerns about the crank coping with an ordinary clutch. I'm not sure if it's a real problem or just "a feeling".
Maybe some of you have a clue how to solve this?

Great project!

[d2t]

Even taking the carb off, all you will see is the 1st of what I think are actually 3 sets of reeds.
Neil

Where would the extra reeds be? Somewhere within the crankcase? Unless they're micro small, I don't see where they would be physically placed in relation to the cylinder/spacer. Also, I still don't understand how the piston can withstand 30K RPM. Not doubting anyone's ideas but there's something still missing in this puzzle.

[2005bully]

The picture with the superimposed piston needs a small piston diameter through the plate,maybe 30mm diameter, and like a tapered top hat above the plate. Then you just need reeds for the induction to fill the pressure chamber, and reeds to control the out flow to the ports at the right time-these will be in the spacer plate. Neil

Neil..... I follow and agree with much of your concept but am a little muddy on the above part of it. Am I correct that you are saying that the fresh mixture which is compressed before transfer begins, is done so by a pump that is created through the application of a 2 stage piston? Kermit Buller

[Grumph]

You bet me to that post teriks.

It's two friends of mine that is building the car.
Totally insane and a lot of high class craftsmanship.

The biggest concern right now is to sort the drive train.
CVT, auto or manual is the question. Know they have concerns about the crank coping with an ordinary clutch. I'm not sure if it's a real problem or just "a feeling".
Maybe some of you have a clue how to solve this?

Great project!

Off topic sure, but it's a 2 stroke. I'd be concerned about shock loads too if you used a conventional automotive clutch...
Only 2 optioms IMO. Both provide initial slippage. Auto or a slipper clutch same as fuel dragsters. They're adjustable for static pressure and dynamic pressure too. Should stop the crank twisting - at least on launch....

[Lightbulb]

Where would the extra reeds be? Somewhere within the crankcase? Unless they're micro small, I don't see where they would be physically placed in relation to the cylinder/spacer. Also, I still don't understand how the piston can withstand 30K RPM. Not doubting anyone's ideas but there's something still missing in this puzzle.

It is only my assumptions, but they would be in the spacer housing. The spacer does not have to be only 20mm thick or what ever we see from the outside.
Neil

[Lightbulb]

Neil..... I follow and agree with much of your concept but am a little muddy on the above part of it. Am I correct that you are saying that the fresh mixture which is compressed before transfer begins, is done so by a pump that is created through the application of a 2 stage piston? Kermit Buller

Yes, that is exactly what I think is happening. Even though it may not pump the same static volume of mixture compared to a conventional 2t, I think that the better mixing, creating a better burning fog with less exhaust residue becomes more efficient overall. CO really does kill combustion, so the less CO that is residual in the cylinder, the better it will perform. Also, it is the only way I can see that the engine can get to breath, at higher than the pipe design length, making what we think a pipe does, infact being wrong. But all these ideas are just my own conjecture that seem to fit all the snippets of information that many people have shared. Of Course we all just have to wait and see what they have really done. But the mental exercise and looking at the concept from a different view point is in itself very refreshing. To me it is anyway. If the lower part of the piston is smaller than the bore, so a reversed dunelt piston but changed, then there is not considered by the rules pumping by a displacement greater than the swept stroke of the engine. It also would not be double pumping either. I am not sure of the mechanics of it not breaking itself or how it can handle the high rpm, maybe there is an aspect of the piston design that can be made in such a way I have not thought of, that as a result becomes lighter and stronger at the same time.Certainly a shorter rod is lighter right off the bat, and a lower gudgeon pin will mean that area of the piston will be cooler and therefore stronger anyway.
Neil

[2005bully]

Neil... Thanks to Google I now know that a Dunelt piston is stepped.... . Based on Ryger engine information listed on this forum, your basic principles are quite valid... IMO Simpler methods of implementation may still be available.... Example... Even the most experienced machinist is going to get goose bumps thinking how to machine, locate, and maintain the two bores with the required concentricity. Not impossible, but difficult at best. Another is the design of "transfer" reeds, providing adequate flow capacity in the time available. Your implementation of stiffer reed petals, which would have a side benefit of raising their resonate frequency is a good start. Kermit Buller

[2005bully]

As far as piston breakage. Most often breakage that is caused by piston acceleration starts as cracks in the transfer cut outs. If the piston has no cutouts those related stress risers are eliminated. The stress on the rod and piston are greatest near the top of the stroke. Faster combustion properly timed would to some extent help reduce those stresses. (small effect and only under full throttle) 100 to 135cc kart engines with careful consideration's will give acceptable rod and bearing life at extended run periods of 20,000 or higher rpms. That is a long ways from 30,000rpms. BUT I do not recall it ever being stated that the Ryger makes its most usable power at 30,000rpm's. Just that it is capable of running to that high of rpm's. Maybe acceptable piston life will be in minutes not hours???? Kermit Buller

[AndreasL]

Thanks for your input Grumphy.
I think you are right.

[Leed]

the head may be standard 2T but what screws into the sparkplug hole? see Frits' photo attached hiding air injection/ignition?

Husabergs Honda 4 stroke link http://world.honda.com/powerproducts-technology/exlink/

to make 70hp at 30,000 I think it needs to make 85% of peak torque (assume at 13,000)
with less time it needs improved thermodynamic efficiency and/or greater pressure difference (flow through same port areas), and or later, quicker opening (what we might be hearing as it tears away at high revs)
improved efficiency from insulated cooler charge, at high pressure, with a 4T bottom end (cleaner emissions, burn/work done) cylinder/piston port not crankcase induction
we see a standard alloy crown in mock up - doesn't mean it doesn't run with a ceramic one - if the combustion (chamber and piston) can operate at (higher) flame temperature then less heat energy is lost to surroundings (cooling system) and more work is done on the crank
to achieve high rpm needs less mass (kinda goes against long piston theory) piston and short light rod (90mm, materials? beefy CF rod)
the long piston theory requires lots of crown force to be transferred down a long fragile skirt that may contain windows to a gudgeon at the bottom
if a light weight rod can be used then why is it shorter - is the short rod necessary must be to accommodate a linkage or modification of the stroke cycle

from LinkedIn Lennart van den Doel Lennart van den Doel https://nl.linkedin.com/in/lennartvandendoel
-In partnership with another company: Cryogenic treatment for all kind of metal alloys
-In partnership with another company: Ceramic plasma coating for aluminum, titanium and magnesium
-new kind of diesel injector (PFAMEN, porous fuel air mixing enhancing nozzle)
hollow titanium rods can be easily 'printed' with Additive Manufacturing technologies
a hollow rod with vertical only movement would still allow a sealed 4T crankcase if no long piston was used
a 4T crankcase requires cylinder induction
surely the multiple clues mean the 4T crankcase is a confirmed fact


Modena KK1 thermo insulating insert ... (windage and charge expansion)... 'removable insert built with thermally insulating
material, to maintain mixture temperature and improve volumetric efficiency'


as wobbly has alluded, with every factor involved, perhaps it is blueprinted from a pool best achievable ideas
anyone remember theglobe.com