Bourke Engine

[ConnClark]

Originally Posted by GreenHornet

Its popcorn time everyone

Now looking at the engine from an emissions perspective it is my opinion that it would show decreases in all levels except NOx. This is the Achilles heal of the HCCI engines of today.

Actually HCCI has lower NOx emissions than a diesel which is why it is attractive to car makers.

The Bourke design is for all intent and purposes an HCCI engine that helped pave the way for modern designs. So it would not surprise me one bit if we were able to test a prototype and see elevated levels of NOx similar to what we find today in modern HCCI engines. When you run an engine lean this is what you get and this is the reason we do not see these engines to often currently. Honda has lean fuel burning engine technology such as in there Insight Gen1. They can use it because they provide proper catalyst technology to help keep the NOx emissions in check.

The main effort to control NOx is to not generate it in the first place. Trying to remove in the exhaust creates back pressure and eats in to fuel economy not to mention costs more money and adds weight to the car.

The mechanical weak link has always been considered the scotch yoke. Many have tried to overcome and improve upon this and have failed. As of recent there are a few who have succeeded in improving upon the design. The article links below detail just how they improved upon the Bourke design and its significance. These two engine designers obviously feel that the Bourke engine was more than just a scam or lost cause! You can also see my thread how to increase diesel engine efficiency where Mr. Pattakon was kind enough to post more about his genius engine designs.

#1. Advanced Technology for Piston Engines
#2. http://www.pattakon.com/pattakonOPRE2.htm

Again I am going to throw this out when something is not well understood people will be quick to judge and often discredit. When things don't go as planned people tend to give up and throw in the towel way to soon! The Bourke engine is not perfect nothing ever is! I could write a page on how inefficient our current gas and or diesel engines are. However we spend millions on improving them every year! The 2 inventors I provided article links for above believe conventional engine design can be improved upon as do I. What is interesting is they both used the simple Bourke engine design and principles as a basis for conventional improvement go figure!

Things are well understood about the scotch yoke. Collins Motor Corporation built a few engines based on their "improved" scotch yoke design in the 90's. They made a big deal about how it made a more compact engine with less vibration and danced all around to avoid talking about what a fuel guzzler it was and its emissions in SAE papers. For their comparisons they used simulated conventional engine designs that showed much higher fuel consumption and emissions than was being achieved with real engines of the day. Needless to say the hype didn't hold up, people got wise, investor money dried up, they went broke, and nothing became of their technology.

Sinusoidal piston motion and extended dwell time at TDC is not a way to save fuel but just a way to waste it. Any company associating itself with the bourke engine is a scam. They can't get conventional development funding because science and actual experimental results show it won't work out the way they say it does. So how do they get funding for it? They bilk dreamers with false claims of being repressed and accept donations.

The Bourke engine has more than just an incredible short list of parts going for it. The engine can idle extremely low and have almost instant power.

A 19th century steam engine can idle at a complete stop and have instant power but that doesn't make it efficient.

The engine is not dictated by RPM but rather engine load similar to what you would find in an electric motor. At idle it uses a very small amount of fuel unlike our conventional engines.

You made me spit water out of my mouth from laughing at this claim.

The engine can run very lean and to very high rpm. The engine can run a plethora of fuels

( Readily dissproven hype and double speak omitted )

However there are limitations and areas that need worked on and improved that the people who have worked and experimented with these engines will tell you. They will also tell you that even Mr. Bourke new it had limitations and was quietly working on improvements as most all great inventors do. He ran out of time before he could implement his improvements. Had he had more time who knows where we could be today!

I know where he would be. He would be hyping the Bourke engine with a bunch of other scammers because his patents ran out.

Engine control and fuel injection are 2 areas that could really use improvement with the Bourke engine and modern fuel injection has matured to the point this could definitely be a possibility. Also engine electronics has improved and matured as well so this could have potential in helping control the Bourke design.

This still won't fix the problems of wasting energy compressing the intake charge twice and extracting power only once or wasted heat due to extended dwell time at TDC.

Now a few things I would like to make clear. First I am no engine design expert and second I am no Bourke engine expert either. I have come to my own opinions and conclusions from research not only from internet readings but also by talking with people who have far more experience in engine design than I as well as people who have first hand knowledge and experience in Bourke engines and the like.

Does the Bourke Engine deserve the Unicorn Corral maybe for some but for me I think it has much potential and sometimes it takes looking out of the box to see such potential. I can appreciate others opinions such as ConnClark and he brings up very valid arguments. Good arguments are constructive for improvement in anything and is something I highly value.

At this point I am so immersed into my kit car project Tigon that there is no way I have the time to build a prototype engine and perform testing to help us gain better knowledge into its claims. However once the car is complete and tested I will have much more time on my hands and would be willing to put my time and energy into such a task of helping us to understand the Bourke engine design much better. Until then the best I can do is talk to others and try to gain insight that way. Which to this point has showed me that The Bourke engine design is very real and not a scam. Also that it has helped us gain valuable insight to HCCI design and other engine design platforms that will help us to improve our current conventional engine designs and theories way into the future.

Oh and as far as the point about poor piston ring lubrication which I did not forget to mention btw because they are more than adequately supplied with oil by a small hole in the cylinder wall at bottom dead center However I do love the Frantz by pass oil filter for our current conventional engines and will utilize it in my small 2 cylinder diesel in my Tigon hybrid design...

GH

Regardless of the location of the lubrication hole it will still be exposed to blow by from the piston rings and that is going to contaminate the oil. A small hole might mitigate it to some degree but will likely foul and plug up.

The patents on this engine have been expired for decades. No one has made it work to be competitive with existing decades old technology. Glaring flaws from an efficiency stand point cannot be overcome to make it work efficiently. Getting rid of the flaws means omitting the scotch yoke and the compression of the intake charge by the piston. Doing so leaves you with a conventional two stroke with scavenging done by an external blower which is no longer a Bourke engine and thus has promise.

If you want something that is considered thinking out of the box try a rotary Atkinson cycle engine. It has thermodynamics working in its favor.

File:WikiDartEngine.gif - Wikipedia, the free encyclopedia

[freebeard]

That's interesting. It's like a Tesla turbine with the flow reversed. Has anyone gotten that sliding inter-connector to work? Do you like that better than Scuderi's approach?

Do these require spark plugs? I'm not seeing any on the Rotary or the Bourke.

Who wouldn't want frickin' lasers in the heads?

[GreenHornet]

HCCI yes can have lower NOx emissions than a diesel however a diesel with little modification can greatly reduce its emissions as well. Just utilizing a biodiesel blend will reduce emissions greatly in all categories!

"The main effort to control NOx is to not generate it in the first place. Trying to remove in the exhaust creates back pressure and eats in to fuel economy not to mention costs more money and adds weight to the car."

Completely agree with this 100%

"Things are well understood about the scotch yoke."

I agree with this also!

The lubrication system in a nutshell uses oil seals to prevent the pollution from the combustion chamber (created by piston ring blow-by) from polluting the crankcase oil. This helps extend the life of the oil as it is used slowly for keeping the rings full of oil to hold and use to lubricate.

As for fuel economy that is up for debate but from my brief readings I can confirm the 400 cubic foot model did suck an awful lot of gas. I will post what I find in details to this thread later as I have to get going now.

I will definitely look into the rotary Atkinson cycle engine so thanks for sharing that! Another engine I thought looked interesting was the Fre-Piston design but that is for another thread entirely.

GH..

[Teemo]

Hello!

The Bourke engine seems indeed genial. Having put a lot of thought into it I must conclude that:
-It is so much misunderstood because it uses RESONANT effects that are not propery documented. This is why it is hard to duplicate, all the air and exhaust channels must be exact length and shape.
-It uses some kind of partial internal EGR that makes it so efficient
-The Bourke left some important aspects to himself because of the fear of being rejected from manufacturing the engine.
-The engine may be unstable at low or changing loads, this may be why it is not had wider use.

Let's hope that we can soon hear about successful refabrication of this magnificent engine, and have better proof of its real value.

Regards

[rmay635703]

Originally Posted by ConnClark

The Bourke engine is a joke when it comes to fuel efficiency.

First lets look at one of its most touted features, the scotch yoke. It keeps the piston around top dead center longer. This does allow more combustion to take place before the downward power stroke and burn more of the fuel, however it also keeps the combustion gasses hotter for longer causing much more heat loss (and thus energy) to the cylinder head and piston. In fact if you look at some of the engines Russell Bourke built you will see they have giant cooling fins on the head for this reason.
.

Looking at this thread (because I have long ignored looking at the Bourke engine) I have often wondered how we might use ceramic on the head and walls to keep the hot exhaust gasses there while also not bothering to dissipate them through the material. An ideal engine would not have any active cooling at all

Ah well pipe dream just like the Bourke engine.

[ConnClark]

Originally Posted by rmay635703

Looking at this thread (because I have long ignored looking at the Bourke engine) I have often wondered how we might use ceramic on the head and walls to keep the hot exhaust gasses there while also not bothering to dissipate them through the material. An ideal engine would not have any active cooling at all

Unfortunately an engine that does not allow heat to escape to the cooling system won't pass emissions these days. The NOx emissions would be too high. In the 80's in Japan they made a ceramic diesel engine once and put it in a test car. It returned very very good mileage numbers, but no way would it pass emissions.

Also NOx emission was the main reason for aluminum heads to appear on production cars and not weight savings. Aluminum conducts heat much much better than cast iron.

You just can't win :P

[samwichse]

Originally Posted by ConnClark

If you want something that is considered thinking out of the box try a rotary Atkinson cycle engine. It has thermodynamics working in its favor.

File:WikiDartEngine.gif - Wikipedia, the free encyclopedia

I don't know, that thing looks pretty thermodynamically terrible. The combustion chamber design has a relatively huge surface area to volume ratio and there's friction points all over the place. Seems like a while lot of work to achieve what a plain old turbo can accomplish.

[rmay635703]

Originally Posted by ConnClark

Unfortunately an engine that does not allow heat to escape to the cooling system won't pass emissions these days.

Also NOx emission was the main reason for aluminum heads to appear on production cars and not weight savings. Aluminum conducts heat much much better than cast iron.

You just can't win :P

Nox can be stored in a sold metal state the same way that solid hydrogen tanks can, perhaps Nox production will someday be considered an excellent side effect allowing you to "boost" your car off self produced Nox when you have to hit the go pedal.

Ah well.

[samwichse]

You're confusing NOx (meaning NO2, NO3, etc) with nitrous oxide (N2O).

[rmay635703]

Originally Posted by samwichse

You're confusing NOx (meaning NO2, NO3, etc) with nitrous oxide (N2O).

No, N2O cannot be stored in solid form that I know of...


NO2 (Nitrous dioxide) is more effective than N2O at lighting a fire

It should work very well if it can be delivered in a non-corosive way.

Nitrogen dioxide, NO2, Physical properties, safety, MSDS, enthalpy, material compatibility, gas liquid equilibrium, density, viscosity, flammability, transport properties

It would accelerate the flame front, if it could be stored in adequate QTYs it would work very well at leaning out WOT enough that one could add some more fuel.

Ah well.