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

 

[gruntguru]

Rod, without going back to check, your specifications seem to have moderated somewhat. They are now all sitting in a realistic zone - except - thermal efficiency. If 52.8% BTE was possible in such a small engine (52.8 is the same BTE as the biggest, most efficient recip' engines in existence), your target market would be every internal combustion engine application on the planet.

je suis charlie

 

[RodRico]

gruntguru,

My numbers constantly evolve as I tweak the detailed build parameters (for things like minimum wall thickness), but I don't recall any big changes recently... biggest was a drop in peak combustion temp from 2150K to 2100K to reduce NOx formation. I know models are only approximations, so my predictions are just approximations. They do suggest, however, that there's a reasonable chance this engine will be worth the effort. Unfortunately, I won't have real numbers for quite some time (I only last week started ordering fabrication equipment and still haven't finished fuel injector design). I don't find the mathematical predictions too surprising, however, because the engine processes as much air mass per revolution as a 49.5cc two-stroke (because each cylinder completes four full cycles per revolution) yet produces only 14% more HP and torque than a Honda GXH50 four stroke geared down to the same RPM. The big gain should be in fuel consumption and volume where the math indicates 45% and 73% improvement of the GXH50... if I come anywhere close to those figures, I'll call it a success.

Rod

 

[Cryptoman]

Tmoose (Mechanical)14 Jan 19 13:17
According to the old Hot Rod article it seems likely it was not Mr Bourke who called it a "one stroke." As I read thru what Cryptoman has provided, David Wolfe, Founder, Bourke-Engine.Com, is the originator of the "one stroke" .

Unfortunate.

WRONG! Dude, read the Documentary!

Dave Kirk!
Thank you, brother! Excellent work! I had no idea this had finally been done empirically!
Has anyone heard of John Allens' scotch yoke engine called the VLB for Very Lean Burn?
It was a single overhead exhaust valved / ported induction with variable under piston transfer pumping....supposedly was successful but due to harrassment and attempted circumvention of his authority and ownership of his patents, he evidently destoryed the entire project and dumped it in the river thames!
I like the design. I think it was much more viable than the original Bourke engine design.
I know of Melvin Vaux's diatribe on Russell but he too was a hot head know it all and continued with Russell's design making small modifications such as a modified cast crank out of a compressor and z cut slots in the piston skirt for relief and smoothing out sharp transfer pumping losses.
I personally interviewed Melvin. Smart guy but was mentored by Russell, evidently.
Melvin ran a 200 cu in 2 cyl. version of the Bourke engine utilizing a square cup in place of the 2 piece yoke plate setup and a half shaft where the cup had a backing plate to prevent warpage under pressure by both cylinders. It was supposedly started on 1K then transitioned over to natural gas and ran a field irrigation pump unattended for thousands upon thousands of hours where he lived in Nevada until he passed on.
Russell also stated that "engines will forever be improved upon" when he admitted his design was not the last word as such!
Snake oil salesman, someome said? What are YOU trying to sell buddy?
You need to read the documentary or stfu!
Again, love your work and report Dave Kirk! Well done!
I have access to Russell's experimental 400 4 cylinder truck / tow boat engine by the way.
Cryptoman

 

[RVAmeche]

I'm not selling anything while you continually advocate support for a design that has no justifiable explanation (a mysterious new cycle counter to known physics, and no actual explanation by the supposed inventor) and no actual data showing it works as advertised (see Dave Kirk's personal tests and the lack of data by every other proponent). Videos of engines running without data are not acceptable.

No one is saying engines aren't continuously being improved as that's clearly not true. There are actual, real, quantifiable improvements being made. But this entire thread, and your comments, imply that "the man" is hiding some super efficient engine in a barn in an effort to...not make money by selling the most efficient car?

 

[BrianPetersen]

Two-stroke uniflow-scavenged engines with ported intake and valved exhaust are known in history ... notably, Detroit Diesel two-strokes were like that.

The combustion concept is independent of whether the mechanism underneath uses a Scotch yoke or conventional connecting rods. Quite a number of more modern two-stroke engines have been developed, and some have been in production or are in production. If we confine the discussion to spark-ignition, several notable examples include the Orbital air-assisted direct-injection concept (in production by Aprilia/Piaggio and Mercury Marine), and the above-mentioned Ficht direct-injection system (in production by Evinrude, which was bought by Bombardier, and its successor is used to this day in snowmobiles and outboard motors using the E-Tec name). Bombardier had another concept called SDI (Semi Direct Injection) which involved using a more-or-less conventional automotive fuel injector located in the transfer port so that injection could be timed late enough to minimise fuel crossover.

These concepts generally use some form of stratified charge in order to facilitate ignition at partial engine load. They generally have large efficiency gains beyond carbureted (or premixed-charge) two-strokes due to less fuel short-circuiting out the exhaust port and more reliable ignition. They are not, however, magic bullets. None of these have found automotive application ... even with catalytic converters, they are still not capable of compliance with automotive emission standards.

These engines don't use uniflow scavenging ... but uniflow scavenging isn't a magic bullet, either.

 

[Dave Kirk]

Gentlemen –

I thank you all who responded favorably to my X-4 engine endeavor. Your comments are greatly appreciated! It may have commercial value as an RPV (remote piloted vehicle) engine but I would not want to pursue any man-carrying aircraft due to the liability situation.

Rod – your engine sounds interesting. I’m sure we would all like more details but understand that you may not be in a position to share at this time. Remember, Carnot-cycle efficiency determines the maximum thermal efficiency and for most all IC engines, 65% is maximum. Best mechanical efficiency is around 85% so these are realistic limits. Best of luck and please share what you feel that you can.

Cryptoman – by all means, get the Bourke 400 restored to operational condition and attempt to run it. Should be an excellent demonstration as to why the engine project mysteriously vanished back in the heyday. My prediction is that vibration will be extreme due to the 180 degree crank arrangement and simultaneously firing cylinders will make coupling to a dyno a real challenge. Just be sure to post your findings, no matter how disappointing they may be.

Brian P – thanks for your excellent post on DFI 2-strokes. I worked at Mercury Marine during the ‘90’s and our group was responsible for adapting the Orbital DFI system to the 3-liter V-6. Turned out to be an excellent product. The Orbital is considered a dual-fluid system; compressed air delivers fuel into the combustion chamber in close vicinity to the spark plug, enabling fully stratified operation right down to 650 rpm idle, with no misfires. At WOT, fuel trapping efficiency was around 96% which enabled the engine to easily match 4-stroke engines in bsfc. The engine could be calibrated such that a catalyst could be fitted but max power took a hit. Since there were no regulations at the time requiring a cat, we went for the max performance calibration. Air/fuel mixing was so complete that A/F ratios of 15:1 (stoichiometric) could be run at WOT and thus engine would match a carbureted engine at full power.

 

[Cryptoman]

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

I cteated the animation on a 2D cad program called Disney Animation Studio and filled in the colored gaseous movements frame by frame in Paint! It was created based on John Allen's critiques over the net...
Invented by John Allen in the 1980's..

Ficht Bourke Engine...
It is an exact replication of Russell's engine and it's running with very little vibration per Ficht's claims. One can tell it's producing torque as it's driving a full size prop' / air pump via direct drive. Just like Russell's radials did back in the day.

https://www.youtube.com/watch?v=2139YQElqIA

Dave, your tests although well done, were flawed by using 100 octane fuel. Russell specifically stated NOT to use such fuels to achieve the Bourke Cycle! Not attacking your excellent work, just stating facts.
There is evidently a fuel mixture Russell used to achieve the stated results!

The Bourke 400 has been completely restored to original condition and due to the engineers that got hold of it after it was wrested away from Russell, the cylinder heads are being redone to original specs'.
Testing should occur sometime in the forseeablek future. One of the orignial 400
investors and witness who should still be alive, stated it was running great for many hours. It was indeed running the Bourke Cycle! 200HP at 2K rpm's as stated in the Documentary.

Melvin Vaux had a 4 cylinder 500cc boxer driving a genset under load in video which I do not have on hand. One also shows him running his 2 cylinder 200 irrigation pump.
I still refuse to believe that Russell was some sort of snale oil salesman/huckster. There's just no way he and many others would put so much time and money into the projects if it was bullshit! NO WAY!

http://www.rexresearch.com/vaux/vaux.htm

The vaux engine animations were done by me also.
I witnessed a test run in PA years ago. It was a noisy clattering thing due to the radiuses that followed the arc of crank rotation cut into the shoes which caused a definate bearing slap at the beginning of each power stroke! The alteration to the shoes was an attempt to optimize dwell time to achieve a more complete combustion cycle.
Melvin's original boxer version had flat shoe faces and evidently ran fine on multiple fuels.

GodSpeed!

 

[Tmoose]

Hi Cryptoman,

On Jan 17 you said -

Tmoose (Mechanical)14 Jan 19 13:17

[According to the old Hot Rod article it seems likely it was not Mr Bourke who called it a "one stroke." As I read thru what Cryptoman has provided, David Wolfe, Founder, Bourke-Engine.Com, is the originator of the "one stroke" .

​

Unfortunate.

WRONG! Dude, read the Documentary!

=================================
I based my speculation on the link you posted back on Jan 13. Since the author of the Hot Rod article called it a two stroke, apparently after interviewing Mr Bourke himself.

http://www.projectbourke.com/hotrod.htm

The "Original author of this (Hot Rod) article, George Hill, calls the Bourke engine a 2-stroke. It is not a 2-stroke engine.

It is a 1 stroke engine taking care of all 4 cycles in one stroke 2 times per revolution!

​

Edited and reformatted for clarity and content by David Wolfe, Founder, Bourke-Engine.Com."​

 

[waross]

Same word, different definitions.
Different strokes for different folks!

It is a 1 stroke engine taking care of all 4 cycles in one stroke 2 times per revolution!

Are we down to one half stroke now?
I can see a double acting steam engine being classified as a one stroke.
Each stroke in either direction produces power.
Now how can we implement that in an internal combustion engine?
Seriously the main point is that there is a chamber above and below the piston and isolated from the crank case. That is also done in the big Wärtsilä-Sulzer RTA96-C
The second chamber requires a rigid con rod and seal.
The Wärtsilä-Sulzer RTA96-C uses a cross head and a second con rod to transform this linear motion into rotary motion.
The Burke uses a Scotch yoke.
I imagine that this could also be done with a cam arrangement.
I am wondering about the efficiency of compressing the pre-charge and losing heat to the cylinder walls or crank case housing and then losing a little pressure and volume as the pre-charge cools as it expands. Lost heat that must be made up in the compression and power strokes.
How does that compare to the efficiency of a low pressure scavenging blower as used on the old Detroit 2 cycle lines?

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

 

[malbeare]

here is another ultra short stroke twostroke con engine.
Link

Link

A tidy mind not intelligent as it ignors the random opportunities of total chaos. Thats my excuse anyway
Malbeare

http://www.sixstroke.com

 

[gruntguru]

This talk of "one stroke" engines is nonsense. Even a double acting steam engine is a "two stroke". The space above the piston (a "working volume") is driven down by steam on the power stroke and exhausts the steam during the upstroke where the cycle recommences. The space below the piston is a second "working volume" executing a separate thermodynamic cycle. Likewise a scotch yoke engine with two pistons combined to form a single rigid body, has two working volumes and is effectively a two cylinder engine.

je suis charlie

 

[BrianPetersen]

Wasn't the only nonsense spouted by that engine's inventor or its proponents.

 

[RodRico]

malbeare,

It was only after clicking your link that I realized you meant to say "here is another ultra short stroke twostroke cam engine." Reading the two articles you linked, I must say I found a good number of surprising technical statements and claims. Far too many to go into, frankly.

The comments about the Split Cycle LLC engine made by the firm's president in 1998 at this page are damning and lead me to think the project was doomed to failure (though only after several changes in ownership... Split Cycle LLC -> QVEN Limited -> Industria Limited -> ??).

The tale of woe surrounding this particular split cycle engine is reminiscent of the Scuderi Split Cycle Engine that was the subject of an SEC investigation and lawsuits against the company by Hino Motors, a subsidiary of Toyota, back in 2015 resulting in seizure of Scuderi's bank accounts. The Scuderi Group (

http://www.scuderigroup.com)

lists all the associated patents but doesn't appear to offer a product.

The only split cycle I know of that's still being pursued is the Tour Engine (

http://www.tourengine.com)

which is currently working a couple of DARPA and Department of Energy contracts.

Rod

 

[Dave Kirk]

Examples of 1- stroke engines - pistol, rifle, shotgun, cannon.

The engine business has a rich history of inventors taking money from uninformed investors. Remember the Fish and Pogue 200 mpg carburetors? More recently, the Rand-Cam engine? How about the "Mighty yet Tiny" engine?

https://www.youtube.com/watch?v=wPc06A8FwN8&t=31s

Talk about a snake oil salesman! Most of these guys have convincing stories of how their engine is smaller, lighter, more fuel-efficient, etc., without ever constructing a running prototype. They may have a model that runs on compressed air but this is a long step away from a running engine. And of course, test data is never to be had.

I believe that most of these inventors start out with an idea (the easiest part) which they legitimately believe in, but have absolutely no training or education in the field. They quickly get in over their heads after extracting money from the gullible, then quietly disappear into obscurity.

 

[BrianPetersen]

Another common theme is that the inventor somehow gets the idea that a conventional crankshaft and con-rod arrangement is "inefficient", that moving the piston one direction and then the other somehow has a lot of lost energy, etc. Or that there is a lot of friction in the piston rings ... which has an element of truth, and yet the means by which their own inventions are sealed has not only a comparable situation but is usually a nightmare to seal and lubricate properly.

The "split cycle" engines all brag about overexpansion - more fully expanding the power stroke. This is another thing with an element of truth to it. They never talk about the heat and pressure losses associated with their crossover valve, which also has to live in hellish conditions of heat and lack of lubrication. But there's another way to achieve overexpansion ... Fiddle with the valve event timing on an otherwise-conventional engine. It's called the Atkinson cycle. Lots and lots of current production engines use valve timing trickery to achieve this, particularly at part load. There's two such engines in my driveway right now. Sure, it's less glamorous.

 

[RodRico]

Dave Kirk,

I agree 100%. The primary value of math models, in my opinion, is to educate the designer regarding the interactions between a very large number of variables contributing to engine performance. The absolute accuracy of the models isn't very good until a couple of loops of model, build, test, refine, and repeat cycles are complete. Even on the first iteration, however, they provide valuable information that can prevent an engine designer from getting seduced by one aspect of the design without considering the impact on the other design elements. I can't count the number of times I was *sure* I was onto a great improvement when considering only one aspect of the design only to discover it didn't work well with other design elements in the models!

Sadly, there are many "engine designers" lacking sufficient knowledge and experience to even know what they *should* know but don't (ignorant of their own ignorance). The result has been a very long string of failures and widespread skepticism by potential investors. This history is what led to my decision not to even *bother* seeking investment until after I had build a prototype and seen encouraging results in testing by a 3rd party. One reason I decided to build the smaller prototype was because it allows me to build a second and possibly third test platform (motoring dyno, sensors, controls, etc.), each complete with an engine, that could be affordably constructed and shipped to testers.

Brian,

The magic being worked using computer controlled valves, spark, and fuel injectors is astonishing, isn't it? Heck, I think even Mazda's Spark Assisted HCCI engine is pretty much a common engine with clever control over its key elements.

Rod

 

[Cryptoman]

Hey Guys!
So, the infamous 1 stroke, myth?
Look, it's quite simple.
The scotch yoke plates, conn rods, pistons arrangement of parts all connected together = 1 piece!
2 two stroke cylinders on either end.

Come on now....think!
During 1 stroke i.e. 180* of crank rotation we get -
Left end = up stroke = right end = down stroke...
Left end cycles = compression and intake = 2 cycles
Right end cycles = power and exhaust and transfer = 3 cycles
All five cycles simultaniously occuring during 1 stroke = Mono Stroke...

No such thing as Mono cycle, unless you're riding one!

Loved the 6 stroke engine! What a torque monster!
Love all the other cool renditions out there too! Especially the ones that actually work!
Russell's goal, which he achived in his design, was zero parasitic moving parts!
I'm sure any of you will agree, the less parasitic losses, the better!
We're all interested in maximum efficiency i.e. adiabatic operation which is the ultimate goal in any thermal energy converter!
Near to full adiabatic operation was evidently achieved by the Bourke Cycle.
That's the rumor and I'm sticking to it!

Peace!

 

[BrianPetersen]

No, it is not a one-stroke engine. It is a two-cylinder two-stroke engine in which you are stuck with an opposed layout. By your same reasoning, the conventional inline-four 4-stroke engine in my car is a one-stroke engine. (All four events - intake, compression, power, and exhaust - are simultaneously happening distributed amongst the four cylinders.) Accept it ... the Bourke design is a two-cyilnder two-stroke engine. It has two chambers in which the operating cycle occurs separated by 180 degrees of crank rotation.

While your concept statement of "the less parasitic losses, the better" may be true, the problem is that (as RodRico alludes to) just focusing on the number of moving parts ignores a whole series of consequences. For example, the Bourke layout over-compresses the precompression chamber and then throws that work of compression away during the subsequent scavenging of the power chamber, thus encountering a parasitic loss associated with the gas transfer. (Dave Kirk alludes to this as well, and rectified that by simply allowing additional volume for the scavenging-pump cylinder. But doing so deviates from Bourke's dimensions ...)

Adiabatic operation may indeed be an "ideal" in some ways but that also has a series of consequences. Some decades ago, there was an attempt to construct an engine out of ceramic components that could operate at high temperature so as to eliminate the cooling system "losses". Problem is ... you still can't stop the heat transfer between gases and surfaces. High-temperature surfaces pump heat INTO the working fluid in the intake and first good part of the compression stroke. Aside from reducing volumetric efficiency, it increases the temperature at the end of the compression stroke. That is not a big problem for a diesel engine since there is no fuel in the intake charge (aside from raising NOx emissions!), but it is a big problem for a normal premixed-charge spark-ignition engine, probably forcing the compression ratio to be lowered.

I see nothing about the Bourke engine that would cause heat transfer between gases and surfaces to magically be stopped. (And if there is such a thing, it could equally be applied to an engine with conventional layout. It's independent of the use of a Scotch yoke. It's independent of the use of two linked opposing cylinders.)

For what it's worth, if adiabatic operation of a diesel engine were really a desirable thing, you would think that ceramic piston-tops would show up in production engines, since there is no issue with detonation or preignition. And yet ... the automotive diesel engines that I am aware of, all use aluminum pistons ... not even steel or cast-iron, which have lower heat transfer coefficients and can operate at higher service temperatures.

Maybe there's a reason for that. Hmmm, what could it be??

 

[RodRico]

cryptoman,

We get it. Nobody is confused. We're just objecting to your distorting the commonly accepted use of the term "stroke" in reference to engines.

Neither I nor, I suspect, anyone else will agree "the less parasitic losses the better" without comprehensive analysis showing the *cost* of eliminating those losses in other aspects of the design. That's what both Kirk and I were alluding to when mentioning folks who get fascinated by one aspect of a design without comprehending the whole system and all its variables.

Yes, renditions are cool. They're even cooler when they explain the operation of a working engine. The ultimate, however, remains engines that have been tested by third parties using established methods. That's how engineers separate ideas that actually work from appealing *looking* ideas with no substantiation other than flowery words and high expectations from non-engineers lacking any knowledge of thermodynamics, friction, air flow, and so forth.

Rod

 

[Cryptoman]

Acadamia! The art of being right!

https://youtu.be/J2weoTGsi5c?t=204

Russell also brought up, if not created the idea of the Free Piston engine!

Russell put his money where his mouth was and was evidently successful in proving his theories in many ways!

The game goes on!

Peace