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Interesting engines

Discussion in 'The Pub' started by Mr Flibble, Aug 2, 2011.

  1. I like hearing stuff like this, just a bloke tinkering and coming up with something a bit different:

    1) The Edwards Winged Rotary - would be interesting to see an actual working prototype, but will it end up in the same dustbin as the Sarich Orbital Engine?

    2) The Di Pietro Motor (compressed air - this one looks like it's actually going places) http://www.engineair.com.au/

    There's a plethora of steam engine designs around too, I like this one:
    3) Green Steam Engine
  2. I watched that whole clip, and I'm speechless.
  3. THat winged thing is fascinating.

    Poor bugger, not only can he not get investment backing, it sounds like he can hardly breathe too.
  4. If I win the lottery I'm giving that guy $10mil to develop that engine. that thing is awesome. I could only be bothered watching about a minute of it but it seems absolute genius.
  5. Mmh, I'm not sold on the winged rotary.

    It's hard to separate the errors in terminology or one-sided explanations from the basic underlying concept he's describing, though. (e.g. "600% more efficient" - he's describing power/displacement 'efficiency', in the same sense a 2-stroke or conventional rotary engine is 'efficient' for having more bangs per revolution than a 4-stroke. Or saying that centrifugal force aids the compression phase, yet saying nothing of the centrifugal force consuming energy from the expansion phase.)

    No discussion of the actual or effective compression ratio either. :S

    And instead of 3 apex seals to get right like a conventional rotary, there's 4... 8... umm.. Potentially 12 or more surfaces that have to seal perfectly? I'd like to see a working prototype, heh.
  6. I'm sure there would be plenty of independent analysis when/if there is a functioning prototype.

    In theory, the thing is pretty cool.
  7. And in theory the Wankel was supposed to revolutionise internal combustion. Sure it produced a series of excellent sport cars, but it was also the power source of several not so excellent not sports cars.
  8. I'm not sure it would be a goer - I reckon sealing the wings would be difficult, and the 'cam' (the grove that guides the wings up and down) would be subject to excessive wear.

    Be happy to be proved wrong though. It is a very interesting design.
  9. I tend to be sceptical of air motors for general use. Not because they don't work. They do, very well, for many specialist purposes. However compressed air is a completely shite medium for energy storage. It just doesn't hold enough. This site has a good explanation of its shortcomings and also has extensive details of a wide variety of other weird and wonderful ideas, some more successful than others. I particularly like "Non-Circular Wheels" myself :D.
  10. The issue with rottery engines, as i understand it, is the seals always wear out very quickly. Unless I missed something he hasn't solved this. He's also got a hella lot of moveing parts where friction and wear are going to be big problems - Wankels have very little moveing parts, that's one of thier big advantages. Spend a few hours around the net and you can find some more really interesting (and confuseing) engine ideas.

    Though with the millions and billions invested into conventional 4S engine R&D and technology, I wouldn't be supprised if said big companies, or elements there of, are doing something underhanded the stump research into new and different tech.
  11. Yeah, seal wear (and sealing in general), the compared-to-a-4-stroke terrible compression ratio which is fairly critical to combustion efficiency, and the ginormous amount of overlap between intake and exhaust ports - though admittedly the RX8's RENESIS fixes that a bit with the peripheral port design. That and the inability to adjust the timing of the ports short of attacking the engine with a die grinder.

    For compactness and power-to-weight and power-to-displacement they're pretty good though, provided fuel efficiency isn't a concern!
  12. The story goes that owners of the NSU ro80 would greet each other on the road by holding up a number of fingers to show how many times the engine had been rebuilt. :)

    It cost NSU so much in warranty claims that it precipitated their merger with Audi.

    Still one of the nicer looking cars though.
  13. Orbital direct injection 2-strokes were interesting, the dodge neon and ford ka were both slated during development to have 2 stroke engines. The performance in the SR50 ditech was startling for it's size. I think we'd see these in lots of cars, were it not for market conservatism.


  14. Conventional 4 stroke engines have gotten very good, and it is a technology that's very mature and very well researched. Trying anything different is getting very hard indeed, because you're starting at a point where conventional engines were 100 years ago.

    Secondly, industry and consumer buyers are becoming incredibly conservative. Give them something new that does the same job as a machine they know, and they stay away in their droves. Go read the history of the Beech Starship. Sometimes, if you build a better mousetrap, the world beats a path to your door so they can burn your house down. The Starship failed because it was revolutionary, it was a game changer, and too many people didn't want the game to change.

    I have a friend, engineer, racing car designer / builder / driver, who came up with an idea to connect the pistons to the cankshaft via two light weight rods and a bell-crank. Although it means more parts, they are lower stressed parts and cheaper to make. The engine can be made more compact, because you can do clever folding inside-itself tricks with the geometry. But best of all, like the rocker / link arrangement of a modern rear monoshock, you can do creative things with how long the piston spends in the power zone and how hard you accelerate the piston and so on.

    After absorbing 25 years of his spare time and hundreds of thousands of dollars of his money, and investors, he's thrown up his hands in disgust, because the big companies don't want anything new that's game changing, and the high stakes chance men are all in it for the process of business and chicanery - they don't want a new engine selling millions - they want court cases and take overs and sell outs and business piracy. They're just not interested in machines, they're interested in rip-off.
  15. The Sarich Orbital Engine?

  16. That's just plain sad.

    There's a chap in the States who is tinkering with a six stroke engine, which re-compresses the exhaust and sprays water into it. The resulting steam adds another power stroke and also extracts heat from the engine.