The Bourke Engine Solved Virtually All Imbalance Problems In 1930 With Only 2 Moving Parts! 20

[Cryptoman]

thread71-376751
Anyone seen the CMC Sytek Scotch Yoke Engine? Completely kills the imbalance problems that conventional direct couple conn rod types suffer from. Interesting how it resembles the Original reverse cam effect Bourke Engine invented by Russell Bourke back in the early 1930's!
But what about utilizing only half the scotch yoke and applying it to conventional inline 4 and 6 cylinder engines? I thought this up decades ago when I was first introduced by a friend to the Bourke Engine Documentary written by Lois Bourke back in the early 70's. Have wondered what the real world result would be for a very long time and due to lack of resources, have not yet been able to find out. Would be easy enough to simulate on today's super fact computers.
It is very easy to realize that this solves imbalance and piston side loading problems associated with conventonal conn rod setups due to lack of direct coupling of the conn' rod to the throw. This advantege is obvious to anyone who can see and think.
One of Russell's main goals was to cure all vibration problems inherrant in conventional engines.
Also, there is a free piston engine design called the Bourke Engine, invented by Russell Bourke back in the 1930's! Basically a dual 2 stroke cylinder design with pistons fixed to a ridged inline connecting rod through a scotch yoke mechanism that simply imparts power to the rotating mass as it is not directly coupled thereto. Sort of the mechanical version of passive agressive!
Russell Bourke designed the worlds first HCCI engine without realizing it or at least without naming it correctly. His primary discovery and goal was to achieve clean cool environmentally friendly exhaust emissions via an inverted combustion process known in conventional terms as pre-ignition! He so acheived these goals in his design. His purpose was to do away with multiple parasitic power robbing parts and that's exactly what he achieved way back in the 1930's! It's still the worlds most efficient piston I/C engine ever too!
For free info -

http://www.bourke-engine.com

/

http://www.projectbourke.com

 

[BrianPetersen]

All claimed advantages were debunked LONG ago.

And there is zero chance that this design has a higher thermal efficiency than a good modern piston engine, while not having downsides that the inventors never mention.

 

[BrianPetersen]

A search of this forum for "Bourke" reveals quite a few past threads, some of which date back 15 years. If the concept has been known for that long, and nothing has happened by now, it's not going to. It's an easy search, I'm not going to bother linking to all of them.

 

[waross]

"1/4 pound of fuel per HP hour"
Can someone check my math?
That looks like about 47 gallons of diesel per KWHr.
I'm used to seeing consumption figures around 13 gallons per KWHr for gen-sets.
Thirsty.

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[GregLocock]

"Completely kills the imbalance problems that conventional direct couple conn rod types suffer from"

http://www.autospeed.com/cms/article.html?&title=The-SyTech-Scotch-Yoke-Engine&A=0948

Yeah, engines with balancer shafts do tend to have fewer imbalance problems. Gosh, this must be rocket science.

Cheers

Greg Locock


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[GregLocock]

waross, you've lost me. The best engines I know manage around 0.25 lb/bhp hr

https://en.wikipedia.org/wiki/Brake-specific_fuel_consumption

The reluctance of the enthusiasts to actually allow proper witnessed tests of the engines speaks volumes.

Cheers

Greg Locock


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[waross]

Thanks Greg I didn't think my numbers looked right.
I'll look for my mistake.

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[RodRico]

The Bourke engine depends on reversing sliding bearings, and they are its Achilles heel. These bearings operate at high peak speed under heavy load with one of two minimum speed regions (where hydrodynamic lubrication ceases) occurring near TDC where pressure is high. These issues can be mitigated using linear roller bearings, but they add a lot of weight and thus increase materials stress in reciprocating assemblies. Furthermore, its obvious the connecting rod and bearing arrangement results in forces being asymmetric around the connecting rod axis and there *is* a crank arm, so the claim of "balance" eludes me. To the extent the engine exhibits balance, it's due to the arrangement of its pistons, not its characteristic Scotch Yoke mechanism. Finally, the claim "It's still the worlds most efficient piston I/C engine ever too!" is unsubstantiated and thus unwarranted.

 

[enginesrus]

If it only ran maybe 100 rpms max it may work. RodRico sums it up nicely.
The most efficient piston IC engines are the large 2 stroke marine engines not the one of this thread. And the Op engine made by Fairbanks Morse likely is as good as the large marine engines as well. Note for those sliding bearings to come close to lasting there would need to be some sort of flexible hose or sliding tube to feed oil pressure to them, even if they were a roller system like some cnc machine tool linier roller bearings are. Opps I see Rod mentioned them first.
They look like a manufacturing nightmare, I don't think that system would be very compatible with the now common practice of all aluminum engine block/ head construction. Recip engine balance seems to be a non problem nowadays, in automotive applications. I am guessing that the reason we have not seen this design being used is because of the excessive wear that it would cause, and the high costs of machine work and materials needed to make them last. The old crank train we are all used to is very difficult to replace when it comes to reciprocating pistons, it is efficient and works great even into the 20K rpm range maybe even more.

 

[Cryptoman]

Hah! Sounds like a Piston Slapper Club chat group!
I know exactly how you feel!
I would love to see conclusive test results myself some day!
Like Russell Bourke say's in the Documentary "you have to throw out everything you know about conventional engine design to understand the Bourke Cycle!"
The Bourke Cycle is what I call an Inverted Combustion process. The entire combustion / thermal cracking process is 100% complete before the piston gains mechanical advantage over the throw and begins its downstroke with the resulting pressure charge which cools during expansion rather than a flame front pushing the piston downward! That should tell you everything you need to know with regard to why you need to re-think the process hence design!
See for yourselves gents'!
We also have access to the original Bourke 400 4 cylinder prototype discussed and shown along with the 30 and various configurations thereof as well as his low rpm high torque naturally quiet 4 cylinder radials! All are direct drive except for the 30 twin.
The 400 boasts over 200HP at 2000 RPM. Same low EGT's!
Peace!
It's free!
Enjoy!

http://www.bourke-engine.com/engine/video.htm

 

[BrianPetersen]

I see spark plugs.

 

[RodRico]

Hmmm... it seems the OP wasn't really asking a question but promoting a website where one can buy Bourke Engine paraphernalia. If anyone is interested, the primary item ("Bourke Engine Documentary by Lois Bourke") is also available on several free energy sites, so make sure to shop around for the best price. Completely unrelated but rather interesting is the dialog between GregLocock and someone attempting to spread the unsubstantiated claims regarding the Bourke Engine via Wikipedia. See

https://en.wikipedia.org/wiki/Talk:Bourke_engine

 

[SomptingGuy]

Whenever I hear terms like "mechanical advantage" and "pushing the piston downward" when describing an IC engine, I wonder whether the inventer uses PV diagrams or just relies on thought experiments.

Steve

 

[GregLocock]

We've had various enthusiasts pushing Bourke on eng-tips as well. Predictably absolutely nothing has been heard of them since. I'm not sure how much a dyno session at a calibrated dyno facility costs, I'd guess $800 for a day, which would be ample time to generate a bsfc map demonstrating the claimed wonderful economy of the Bourke engine. The fact that NONE of these blowhards has ever even demonstrated a running engine, never mind putting one on a third party dyno, is fairly telling.

So far as piston slappers goes, actually that was a job of mine once, solving piston slap, on real production engines.

Cheers

Greg Locock


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[RodRico]

The tale of a "successful" test of the Bourke Engine by the men who inherited the engine from Russell Bourke himself. In the very last paragraphs of the tale, the "remarkable" results are revealed to be the product of an error in measuring horsepower.

http://www.niquette.com/books/sophmag/bourke.htm

 

[GregLocock]

I actually emailed the author of that piece, he confirmed that it was an accurate account in his recollection.

Cheers

Greg Locock


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[BrianPetersen]

A flat-four arrangement of a Bourke engine requires a first-order counter-rotating balance shaft. A flat-four conventional engines (with the pistons moving in a "boxer" arrangement) does not. The first-order balance situation is the same as an inline-twin with a 180-degree crankshaft. I have an engine like that in one of my motorcycles ... it has a balance shaft.

A flat-six arrangement has the same first-order balance situation as a conventional inline-three. Again, it requires a counter-rotating balance shaft in order to run smoothly. A flat-six "boxer" does not.

For that matter, a flat-twin arrangement of a Bourke requires counter-rotating balance shaft(s). A BMW flat-twin motorcycle engine does not!

Yeah, the piston motion is sinusoidal. The higher-order vibration effects are irrelevant if the first-order vibration is bad.

So, the claimed solution to "imbalance problems" is a crock.

Now, for the combustion system.

Yes, with purely sinusoidal motion, the piston spends less time near TDC than a conventional engine with swinging con-rod does. So what? It fundamentally doesn't change anything. Alternate combustion systems can be used with a conventional crank-and-rod arrangement just as well (or just as badly). The slight change in motion profile isn't going to drastically change the combustion process and its resulting efficiency, and its resulting emissions. It just isn't.

I suppose there is a slight theoretical benefit of connecting the piston in the middle rather than at piston pins, to conduct heat out of the middle of the piston and to take the load right in the middle - shorter load path, shorter heat transfer path. But, this is splitting hairs.

 

[Cryptoman]

"The Bourke engine depends on reversing sliding bearings, and they are its Achilles heel."

W R O N G ! ! ! ! The CMC Sytek uses a slider and worka perfectly! The lubrication issues were fully addressed and solved. The Sytek engine was proven viable via thousands of hours under load on a fully outfitted dyno/emissions etc. test rig AND was also test run in a few different vehicles on the roads for 10's of thousands of miles and has been ready for mass production and consumption for years now.

It was blackballed by the Cartel's because it was just too darn efficient killing Bourke's dreams of seeing his engines in broad use across the world staving off the now polluted biosphere we suffer from that he envisioned way back in the early 1900's and set out to avoid through 'complete thermochemical combination of carbon and oxygen basically yielding air and water as it's exhaust products @ substantially lower egt's as a result thereof, which were evidently achieved in the Bourke Cycle! Hence the arrangement of parts and form of engine. The use of ported valving was practical due to ultra high combustion temps' which back then would melt poppet valves but with today's high temp' materials, the Bourke Cycle can also operate safely in an overhead valve configuration both 5 cycle 2 stroke and 4 cycle 4 stroke mode.

The Bourke engine utilizes what Russel Bourke called the Tripple Slipper Bearing. See animation:

http://www.bourke-engine.com/ani

As you will see, a 3 layer high speed rotary bearing that SPINS on it's own axis in the opposite direction while spinning on the crankthrow and rolling across the shoe faces of each connecting rod that is solidly coupled through the yoke plates yielding a 1 piece assembly.
Debunked? I don't think so, not if you know the differences between opinion, rumor, fact and fiction and of course what 'constitutes actual proof'!
Please witness accordingly....
Watch the video clips of the Bourke 30 001 production engine hand made by Russell Bourke, acquired by Bourke-Engine.Com on behalf of Roger Richard linked in this thread.
Roger's prototype 30 is also feature which he made from scratch for want of an actual Bourke 30, running the Bourke Cycle itself! The man is a genius mechnaic, machinist and engineer just like Russel Bourke was!

And, True, the Bourke Engine Documenary is available all over the place but none of the other products offered are or should be due to copyright protection.

Not saying nor has I ever claimed the Bourke Engine is the end all be all form of IC piston engines but it's a damn good step in the right direction any day and I am not aware of any engine in production that is anywhere near as efficient as it was! Please correct me of I am wrong for I am keenly aware that inventors are coming up with new innovations all the time, which is great!
GodSpeed!

 

[BrianPetersen]

The combustion system doesn't "know" the mechanics of what's moving the piston. The means of air, fuel, and ignition delivery into the cylinder don't care that the piston is being operated by a Scotch yoke rather than a connecting rod. It doesn't make any difference. The slight difference due to pure sinusoidal motion is splitting hairs.

As far as I can tell, the Sytek demonstration engine was a four-stroke, spark ignition, stoichiometric air/fuel charge, Otto cycle.

Carbureted (premixed-charge) piston-ported two-strokes have awful fuel consumption and emissions. END.

Direct-injection spark-ignition two-strokes are in production (with normal connecting rods) - see Bombardier/Rotax/Evinrude E-tec - and although they are considerably better for fuel consumption and emissions than carbureted (or, at least, premixed-charge) two-strokes, they still use spark plugs, they still need a catalyst in the exhaust system, and they are not capable of meeting current automotive emission standards. (They are used in applications not subject to those standards.)

The "detonation" cycle, a.k.a. HCCI, doesn't work outside of the laboratory.

The video of the Bourke engine that I saw somewhere on the internet, had spark plugs.

Spare me the hand-waving (in the above post). Show me the P-V diagram, show me the means of ignition, show me how it achieves reliable ignition at any combination of engine temperature, ambient temperature, and engine load. Show me how it's preventing premixed-charge from being trapped in crevice volumes (and I will fully grant that the two-piston arrangement may be capable of reducing, but not eliminating, the crevice volume above the top compression ring). Show me how it's preventing premixed-charge from being quenched (stopped from burning) adjacent to chamber walls that are inherently at a temperature lower than ignition temperature (by quite a bit). If you are also claiming that combustion goes all the way into the boundary layers and crevice volumes because the temperature in those places is kept high enough for ignition, show me how it's preventing pre-ignition.

 

[RodRico]

Cryptoman,

As the one asserting the superiority of the Bourke Engine, it's incumbent on you to provide objective evidence, not on everyone else to prove it can't work. You arguably have more information than anyone, and promote a web site selling that information, yet you've produced no actual evidence. I note you've also conveniently skipped over discussing the fact that a simple error in measuring horsepower by the Bourke team has been identified that explains it's alleged performance better than any measured test results you've produced thus far.

I love how folks pushing free energy or super-efficient engines that never caught on always turn to conspiracy theories; "Big oil suppressed it!" How do you explain the very public interest in the Achates Engine, Liquid Piston, Mazda's Spark Assisted HCCI, or Infinity's VCR engine?

Unsubstantiated absurdity. I don't have time to argue mythology any further.

Rod