Experimental Engine Designs
 

Over at this thread there's a discussion of the HCCI engine.

This got me wondering -- what else is being tested out there for purposes of FE?

RH77

In another thread, Telco mentioned this 6 cycle engine: https://www.autoweek.com/apps/pbcs.dl...THISWEEKSISSUE

Idea is simple enough. Typical 4 cycle is of course "intake, compress, power, exhaust". The 6 cycle adds 2 more, "steam power, exhaust", by squirting some water in, which provides a lot of push when it turns into steam. And it cools the engine so much that the traditional cooling system is not needed.

I got to thinking about this. Sometimes, especially in cold moist climates, water can collect in the gas tank. Engines run poorly when this happens, as gas and water do not mix. The number one technique for dealing with this problem is adding some alcohol which will mix with water. But I wonder if water could be a help instead of a problem. Would a 50/50 ethanol and water mix still burn? If it does, would that give the same benefits as the experimental 6 cycle engine, and with more convenience?

Conventional steam vehicle propulsion went by the wayside with the "Dieselization" of the Railroad industry -- and it looks like we forgot about it. It doesn't require a dangerous boiler to extract steam power. The 6-cycle engine has some promising advantages, but it looks like the trucking industry would benefit the most from an air-cooled or ultra-high thermal efficiency engine. Its application in automobiles? ...and how soon? It looks like it may be a few years off from accepting load.

What I'm finding is that tech of the past, which has long since been abondoned, could be researched today. With the advent of microprocessors and advanced electronics, old-school ideas may be able to be controlled -- where they gave up on it before due to this lack of technology.

I like the Scuderi engine as well, but I'm wondering how they're handling the 100:1 compression ratio. I need to read-up on it more... Again, the scavenged, compressed air could be used on pneumatic brakes of the trucking industry or in stationary applications. Where it comes into play for cars wasn't mentioned...

Neat ideas...

RH77

RH77 -

Here is a "toroidal" engine, aka a "donut engine" :

New Toroidal Internal Combustion Engine Promises 20:1 Power-to-Weight Ratio
18 April 2006
Attachment 876

Here's the company :
https://www.angellabsllc.com

I saw this company at the LA Car Show (basement section) :
https://www.angellabsllc.com/2006-02-...uto_photo.html

It's promising to be a smaller, lighter engine with the HP of bigger engines :
https://www.angellabsllc.com/Scenario.html
Attachment 877

However, if you notice, in the news section, the last update was April 3, 2006. Sooooooooo, they may have hit a snag.

CarloSW2

Other possible attempts at HCCI
 

There have been anomalous claims of engine efficiency over the years that related to better ways of burning fuel. I think these were unwitting efforts at HCCI and I am glad to see this finally making the main stream. I had thought for years that we were missing the point in the way our engines ran but I never quite managed to get my mind around the issue until I read about Honda's Active Radical Combustion process. I had experienced something like this combustion process as a kid on a 2-stroke motorcycle but just thought it was a hot spot in the head triggering the combustion. I cut the ignition and the engine continued to run quite well. When similar happened to old man Honda he had the brilliant insight to investigate further.

Here is an interesting engine that the inventor claimed ran on a detonation combustion cycle many years ago. I don't think the claims were ever demonstrated in front of a third party. If it ran as claimed at the efficiency claimed it was a fore runner of the modern HCCI engine. It ran with restricted exhaust and was manually leaned out to what was called detonation after it was running. I think it may well may have been HCCI on some occasions.

https://bourke-engine.com/

Here is a more sanguine analysis of this engine.

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

Here is a modern attempt at this combustion process. I have talked to this inventor. He is a very decent and intelligent person. He is a rational experimenter and generally quite practical. He has achieved very lean burn but there is little reason to believe this engine will achieve any commercial success.

https://www.rad-cam.com/_wsn/page2.html

There used to be a patent application that gave considerable detail of the engine. It dwelled at TDC for about 18 degrees. It used a clever cam arrangement rather than the Scotch yoke. It ran a little higher head temperature and cooler exhaust. I don't think he ever made any claim of any specific fuel consumption. It could be brought to idle RPM at WOT by leaning out the mixture. This was simply a working prototype. I suggested to him at the time that it looked like HCCI but he did not respond to that point. Anyway it is a very cute engine. If he had just ran normal combustion the engine seemed very practical to me. He knew he had to go to MPFI for even fuel distribution and I think he ran out of money at about that point. It is darn cute anyway.

On the subject of HCCI I have long thought that Smokey Yunick's "Hot vapor engine" was burning fuel in a process similar to HCCI. Most conventional engine engineers said it should detonate it self to destruction. For some reason it did not. The fuel economy claims were on par with HCCI combustion also. As a college student I called up Smokey and he talked to me for 15-20 minutes about that engine. This was a few years after it had fallen out of the news. I asked how he was controlling detonation and he insisted there was no secret other than uniform cylinder head temp. He spend a great deal of effort to keep the intake and exhaust sides of the combustion chamber within about 15 degrees of each other as I recall. I asked specifically if he was using EGR to control detonation and the response was generally negative. In any case he got darn good mileage.

https://schou.dk/hvce/

https://www.dieseltech.cc/

It is apparently very hard to get something like this into the market. They have been trying for several years now.

Not sure if it's been posted yet -- but I'm sure there's an engine out there that uses a scotch yoke mechanism. You wouldn't need counter weights, wrists/pins, etc. - Just 1 solid connection to the piston.

Here is one plus the other I mentioned earlier in this thread.

https://www.autospeed.com.au/cms/A_09...ntArticle.html