[Schoenrock]

Hello,
my name is Markus Schönrock. I invented a new kind of Rotary Combustion engine. You can see everything about the RotaTorque on www.rotatorque.com, my privat Homepage. At the moment it is only awailable in German, but there are lots of animations that are easy to understand.
As you can see, the first Prototype is ready and works.
For the next stage of development I want to build the second "evolutioned" Prototype. There are lots of invenstigations to be made, such as electronic ignishion, injektion, some hours Dyno testing and so on.
I need to find people who can help me to start the next stage, so I try to make the RotaTorque-engine as public as posible.

I am looking foreward to your reactions
and hope you understood my bad english

Markus

[smoregrava]

Cool thing. didn't find any pictures of the finnished engine. Have you used it in any application?

[Karl_T]

What are you using for rings? (vanes) That looks like a nearly impossible technical challenge to have a ring that will slide and hold the pressures of combustion.

Karl

[Schoenrock]

Hello smoregrava,

you can find some pictures under http://www.rotatorque.de/page51.htm.
The first engine has only 96 cm³. I had to cool it by dripping water over it.
With this engine I only wanted to test, if my Idea will work. The second Prototyp will be some bigger und with internal cooling.

Markus

[Schoenrock]

Hello Karl,

The engine is completly out of Graphit. Dry operating Vacuum Pumps and compressors work the same way. There is only a very small gap between Rotor and Housing. The sliding vanes need a minimum speed to tighten up.

Sorry, but I really have to refresh my english

Markus

[devincox]

Very interesting design. Any movies of it running?

Devin

[peter.blais]

What would you say are the advantages of this over a conventional wankle type rotary? Odviously, there is no longer an eccentric shaft, but to me it looks like it will complicate the seals somewhat as they are no longer fixed, and we all know the apex seals were always the trouble spot or one of the trouble spots in wankle type engines.

[Schoenrock]

Hello

the oldest version of an rotary vane engine I found, worked with steam:
http://www.dself.dsl.pipex.com/MUSEU...oule/soule.htm
Today there are many different applications for the rotary vane principal:
http://en.wikipedia.org/wiki/Rotary_vane_pump
http://www.everestblowers.com/dryvane.htm
http://home.wxs.nl/~brink494/schpmp_e.htm
http://www.pneumofore.com/technology...vane-principal
http://www.cashflo.co.uk/Vane.html

Nearly in every airplane like a Cessna is a dry running rotary vane vacuum pump installed because of its reliably und they don´t have any seals.
You can also find rotary vanes in industrial compressors and hydraulic pumps.
The only thing I tryed, is to combine the rotary Principal with an internal combustion.

Sorry, I cannot deal with a video. I gave my first Prototype away for some professional Dyno-Testing. A large company (- I don´t want to tell the name at the moment -) that is interested on the Rotatorque, damaged it by turning it much to high. I told them to stop at 3000 1/min but they ignored it.
Now I need to build a new one, as soon as possible.
But it costs a lot of money for a private inventor.

Markus

[RotarySMP]

Schöne Grüßen aus Wien Markus

"Nearly in every airplane like a Cessna is a dry running rotary vane vacuum pump installed because of its reliably und they don´t have any seals." I'd agree that most light aircraft vane vane type vaccuum pumps but wouldn't agree on the reliablity.

How does a graphite housing stand up the combustion process? Have you Chromed your bore?

How do you do side seals? The smallest wankels (model engines) also don't need them if you control the housing thickness to very close tolerances. In a bigger engine, thermal expansion makes these clearances differcult to maintain.

The Apex seal issues of the early wankels were basically solved by the early seventies 12A's. The marketing need to inject a little sump oil rather than a more optimised two stroke type oil also leads to gumming up of the seals in their slots on the Mazda engines. Have you looked into springs behind your vanes to help your sticking issues?

Have you done any dyno work with varying intake and exhaust pipe lengths. Your design should benefit from harmonic tuning in a similar manor to the wankel. Here is a link to a very well done model dyno:

http://gallery.intlwaters.com/thumbnails.php?album=338
http://gallery.intlwaters.com/thumbnails.php?album=351

[Schoenrock]

Dear RotarySMP,

as you can see an the pictures below, the engine is completely made of graphite. Only the drive shaft is steel. The graphite I use is a special mixture for best tribological characteristic. It is also impregnated for high temperature use.
Because there is no material mix with different thermal expansion the gap tolerances from rotor to side housing are very small.
I use only centrifugal force for the vanes. I also tried th pressurize the vanes with compressed air, but it was not necessary. The vanes start tightening up at about 300 rpm. First I tried with petrol-gas mixture out of a small carburetor. When too much unburned petrol is in the engine the vanes may stick.
So I used Propane gas for all my testing.

Markus

[NC Cams]

Sealing has been the thorn in the side of ANY/ALL internal combustion engine designers/builders.

Reason: the violent temperature and pressure in concert with the notorious corrosive properties of the various fuels at the elevated temperatures make it VERY difficult for sealing to occur and to remain viable.

Piston rings use residual tension to force the ring against the wall. They also use gas pressure in concert with uneven cross sectional areas to affect side sealing of the ring within the grooves.

A combination of precision fittting and machining along with controlled slippage allows the rings to maintain a seal with the wall as well as the ring grooves in the pistons

A vane seal relies on two things to make it seal. The most obvious is centrifugal force. This shoves the vane out against the wall/bore to affect a seat at the vane face.

However there is also a pressure differential between the high and low pressure side of the vane. This comes into play so as to force the SIDES Of the vane against one side of the wall. When this occurs, however, a space exists on the high pressure side of the vane. Gas pressure (or fluid pressure in a hydraulic system) is then free to become applied to the BACK face/side of the vane so as to force the vane outward against the wall thus generating a pressure enhanced seal of the vane against the face and sides.

You need either centrifugal force or gas/fluid pressure to hold the ring out against the bore and against the ring land/groove to affect a good seal. Otherwise, compression loss WILL occur and the engine can't/won't run.

The lack of a natural spring in a lip seal in a rotary engine has been a real problem over the years. This is why they have come up with various mechanical spring designs so as to force the seals outward to affect a seal - the natural "spring" (aka outward tension) in a piston ring does this.

Air turbines and power steering pumps use this vane type of pump system to create pressure or extract work out of compressed or expanding fluids. However, in these cases, the operating environment is nothing like that in an IC engine. Stick a vane and these vane pumps won't work which, likewise, will occur if the concept were used in an IC engine.

Over the years, all sorts of neat IC engine ideas have been developed that SHOULD do all kinds of neat things to increase power and efficiency.

However, the simple addition of spark and fuel to the concept quite often brings doses of reality that have prevented the engines from reaching anywhere's near what their creators had envisioned.

Yes, the vane pump concept works in theory but sealing during cranking and under the duress of the combustion process will be your major challenges.

I would NOT count on vanes a pictured in post #8 as being sufficient for the proposed concept. They're probably going to need supplemental springs to affect a seal during the induction cycles to say the least.

[Schoenrock]

Thank you NC Cams for your statement.

In case of the second Prototype I want to calculate the centrifugal force pushing the rotary vanes. The vanes measure 60 x 40 x 6mm an they weight about 30 grammes. The possible continuous turning speed should be 2500 rpm. At this rpm the vanes will be pushed with 16 kg or 35 lbs against the housing. How much load do you think to need for tightening up?
In beginning I thought I need to pressurize the vanes from outside. With the first Prototype I tried it with different air pressure, but it was not necessary. The engine turned even slower because of the rising friction.

I know there will come problems to be solved. No one can aspect to develop a perfect new engine in such short time with only one person.

In 1876 as Nicolaus August Otto invented his Otto-engine he surly did not think about the complicated engines we have in our car today.
Any common rail diesel pump is more complicated than the RotaTorque-engine. The question is, if it is the right way to make the Otto-engine more and more costly by mechanic, just to save a tiny little bit fuel, or to think about another kind of combustion engine.
It is a difficult way because leading engineers will newer admit, 130 years of work may have gone into the wrong direction.

We all have seen what human intelligence is able to build. If I can get the manpower and the money to develop the RotaTorque for series, I am sure everyone wants to get this smooth enormous power the RotaTorque produces without any vibrations or oil change.

Markus

[InspirationTool]

The graphite is interesting.

Doesn't graphite oxidize at high temperatures?

-Jeff

[NC Cams]

Markus: Forget your 2500 rpm vane load calculations and answer this:

How do you plan to have generate sufficient vane tension to be able to seal the engine adequately to crank start it and then have it idle smoothly and reliably???? Even race engines have to start and idle.

Yes, the increase of dynamic seal drag is a real problem when it comes to sealing any IC engine. This is why narrow face, low tension, gas assisted rings were developed and used. They too have their problems associated with them and heat, distortion and pressure are but a few - you know, the nasty things associated with spark and fuel.

Keep in mind that the vane concept you're using works readily at relatively low pressure differentials (50-150psi)across the seal and at very high speeds. But at cylinder pressures of 900-1300 psi peak firing, forces change DRASTICALLY as do component reactions.

Vane type systems also rely on speed as opposed to torque to develop their power. Thus as you try to create a higher pressure differential and run at a low speed, these engines can have some real shortfalls in power output. This is why idle performance can NOT be overlooked when any engine is undergoing development.

I'd encourage you to do a "rotary engine" search on this webside. About 3-4 weeks ago, a fairly long message thread was exchanged regarding the sealing issues faced by a piston port timed engine. Many other issues you may find helpful were also addressed.

Although the thread involved a "build it/machine it yourself wankel", the technological challenges that affect piston sealing are IDENTICAL to those you'll have to deal with.

Yes, there are better engines than the reciprocating IC. BUT, it has survived the challenges of those that have tried and failed to overtake it. Not becauses of revolutionary progress, but rather, evolutionary iterative development.

Besides, unlike a fixed port engine, the poppet valve style engine, as inefficient as it may seem to be, has the unique ability to be adaptable to either low or high speed operation simply by changing the valve timing - not something that piston ported engines can do.

The beauty of the reciprocating engine is NOT in its elegance, but, rather, in is adapability and robustness - brought about by generations of iterative devlopment.

EDIT: No oil change? Absolutely NO engine has perfect and complete combustion. Thus, residual contamination must be dealt with and eliminated. Moreover, even rings and the contact surfaces of the vane and bore need some forme of lubrication. Even so-called adiabatic engines with ceramic lace components had to have lubrication and it had to be changed due to contamination/corrosive remnant issues. Leave this claim or potential benefit on the shelf until you can get past the sealing issues which WILL be formidable.

END EDIT

Best and most engine? hardly.

Robust, affordable and adapatable? definitely.

[jderou]

Geez, give the guy a break. Markus, if you look at the other posts where someone is woking on desiging a new engine, you will see that they are ALWAYS met with people trying to shoot them down.
NC Cams, although I agree with some of your points, what are you doing in your spare time?
It may never beat a piston engine, but its still pretty darn cool to design something different and see it run.

Joe

[Schoenrock]

Thank You jderou,

the last hours I just thought about what I should reply Mr. NC Cams. If my writing hurt anybody this was not my intention. I don´t earn any money with my activity and I don´t dream of millions to get someday.
I am only a bit proud of what I have done the last years and want to tell someone.

Markus

[Schoenrock]

Oh, I have vorgotten to give Jeff-InspirationTool a link to graphite:

http://www.sglcarbon.com/gs/pdf/mecha_data.pdf

Here you can see for instance Type V 1626 this is the material for my vanes

Markus

[balsaman]

Markus,

Very cool. I would love to see a video of it running when you get another built.

Eric

[NC Cams]

If anyone wants to, "...design something different and see it run...", as an engine designer has a want to d, the individual just MIGHT want to pre-solve some inherent problems that that they inadvertently design in that may/will keep if from running in the first place. vane sealing is one of these issues.

Sealing is of a PRIME concern with any IC engine and worrying about 2500 and above rpm sealing is eventually critical, if you can create enough compression to even get it started.

By pointing out the thread where another member and myself entertained literally thousands of readers by going over these exact same issues, albeit as it pertained to a DIY rotary, I felt that I did give the guy a break and simply point out the thread as opposed to restating the same sollutions to essentially the same problem - creating a sliding seal in an irregular shaped housing where the sealing member is constantly seeing a speed and pressure change.

It was his choice to either research it or ignore it. I"d think however, that anyone who went to the trouble of making solid graphite components and obviously go as far as he did to design the geometry as he did, a bit more research in to solutions for issues that he might/would face would be a welcomed offering.

What do/did I do in MY spare time? Studied IC engines for many years. All kinds. Race them too. It was my passion that became my hobby that eventually became my livelihood.

As a result of learning what I did, I try to share it with folks who are embarking down the same path as I only without the 30+ years of experience that I've gained along the way. And doing so while working for some noted suppliers of automotive engine components.

How did I get where I did and in fairly short time (for my age)? I learned from some hard a$$ed senior engineers who were 'kind' enough to share their hard earned knowledge about valves, pistons, rings, bearings, cams and all sorts of other moving parts in IC engines. And this was WAY before the politeness of message boards became the norm and expected - those ******** were down right mean at times BUT they knew their stuff. I learned the electical/electronics side of engines along the way as a side interest.

A budding engine designer has essentially two choices when they start down that path as a hobby or as a profession:

a. they can reinvent the wheel, re-discover and and re-solve each and every sealing, function and/or development problem that has been found and solved over the past 50 years or so of rotary and/or piston engine development (the tecnologies are often intermixed and therefore interchangeable).

Needless to say, an expensive process that is a very inefficient use of time and precious resources.

or

b. learn from the experiences of others regarding what TO do and what NOT TO DO. You can see MUCH farther and learn MUCH faster if you stand on someones shoulders than to stand and gawk around by yourself.

I am NOT trying to shoot the member down. I'm trying to point out the problems that he faces via his enthusiastic albeit oversimplified design efforts.

I feel that the member needs to be made aware of any sealing or design short comings in his design. Why? So he perhaps may choose to solve them BEFORE he does a WTF and tries to start it and finds that the damn thing won't run and then doesn't have a clue why.

After all, it DID run on compessed air but won't run under the duress of spark and fuel. And he did see that as pressure rose, parasitic drag increased (keen observation by the way - don't forget it). Gee? What could be different with spark and fuel? it should be working. Ask know or later but surely they will ask... They always do....

The joy of seeing your creation run can be trashed into ruins innumberable times by poor design and/or development choices that one makes. These are often due to a lack of knowledge and/or experience. I'm only trying to facilitate the attainment of success by eliminating deficiences that are there due to a lack of experience.

It has been my experience that inherent design deficiency issues are NEVER solved by best wishes nor well intended words of encouragement. The proper use of technology and/or problem solving/prevention skills is whats needed.

Markus: I encourage you to find and read the wankel post mentioned above. It may save you YEARS of dead-end development efforts as well as thousands of dollars of needless expense. You WILL encounter them as a developer of a piston ported engine.

On the other hand, you can ignore any of my suggestions and cruise on as you are. Your choice.

BTW: there are some problems developing that are in their infancy:

"When too much unburned petrol is in the engine the vanes may stick.
So I used Propane gas for all my testing."

Low speed sealing is usually achieved by residual tension and/or mechanical excitation of the sealing member. Gas pressure can be more effective and/or dependable as speed and/or cyl pressures increase.. Sticking vanes and/or rings is a real problem in ANY engine. Yes, propane may mask the symptoms but it does little to address the cause.

There is/was a reason why your predecessors used springs to affect a mechanical seal. It won't hurt for you to learn/find out why.

[Schoenrock]

Mr. NC Cams,

about one year ago I heard my Baby breath for the first time. You can be sure that nothing in the world will stop me from bringing some more of these baby´s to earth.

My RotaTorque has run under Fuel and I only tested to pressurized the vans from the outside to the center of the rotor because I wanted to see differences. I thought about putting some engines in a row to get more power. When only half energy is needed I want to uncouple the second stage by sucking air out of this bore. This functions perfect - just little suck and the engine stops immediately.

http://www.rotatorque.de/bilder/druckluft.jpg

My shool english makes it very difficult to translate exactly what you say, but somehow it sounds unfriendly to me.

Thow you seem to know everything about engines, what about useful help instead of criticizing.
My engine has run, just until some high graded German engeneers broke the engine by turning it over 3500 rpm.
The first engine had some mistakes and I wrote them in my Homepage.
Everyone can see the evolution from first to second Prototype.

So If there is anybody who likes to help me completing the engine with a cheap and functional electronic ignition or a programmable gas injection he is welcome. The others may stop making a problem out of everything.

Markus