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Efficient Rotary Engine Lands Million-Dollar Darpa Contract

76 pointsby craigjbabout 10 years ago

7 comments

digitalzombieabout 10 years ago
Did they fix the reliability and oil consumption for Rotary? The rx8 ate a lot of oil cause the oil lubricating it evaporates. Also the Rx7 rubber hoses tends to wear down over time.<p>While the rotary did won Le Man 24 hr endurance race, it is still plagues with problem. These problems isn&#x27;t because Pistons are better but because Pistons had tons of time refining it. Rotary so far have been neglected and it seems like EV&#x2F;battery technology will be the future while hybrid is just an intermediate step between oil and electric.<p>Another interesting engine that GM tried was Turbine, jet engine for cars. It sound like a vacuum cleaner.
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aidenn0about 10 years ago
I know the intent for this engine isn&#x27;t for road-legal cars, but...<p>This runs on Diesel, and advertises a low-temperature exhaust; can someone who knows more tell me if diesel&#x27;s need hot exhaust for emissions reduction? I know that they tend to use EGR for NOx, but every car with a diesel I&#x27;ve seen still has a catalytic converter to do <i>something</i>.
mattlutzeabout 10 years ago
The benefit and trouble with rotary engines is their reliability -- fewer moving parts means they&#x27;ll generally fail less during their life cycle, and running them under higher loads &#x2F; higher output, within their specifications, will generally not reduce the life expectancy (as in, run a 100HP rotary continually at 30 or 100, nearly the same running life).<p>But they will have a shorter overall lifespan. That large moving inner chamber and the outer chamber walls around it will wear down, and when they fail you replace a significant amount of that combustion chamber (or just junk the entire motor).<p>It&#x27;s a neat application of the technology, and particularly in contexts where either the motor is going to run for long periods at a specific speed or not be used all the time, it could make a great option for power generation.
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x0054about 10 years ago
From Another Article: The compact design of LiquidPiston&#x27;s lab engine currently tips the scales at 80 lbs for the 40-hp model. It would weigh less than 50 lbs in production, the company claims, far less than a comparable 40-hp diesel that would tip the scale at around 400 lbs. [1]<p>How on earth do you get a 400lb diesel engine that ONLY produces 40HP. First, when comparing engines for power production, you should really talk about kW production capability, not HP. Engine&#x27;s HP is only half the story, you also have to talk about it&#x27;s torque.<p>I know rotary engines are a cool technology, but something about this smells like BS.<p>[1]<a href="http:&#x2F;&#x2F;www.popularmechanics.com&#x2F;cars&#x2F;a8174&#x2F;liquidpistons-hyper-efficient-engine-turning-the-rotary-inside-out-13817971&#x2F;" rel="nofollow">http:&#x2F;&#x2F;www.popularmechanics.com&#x2F;cars&#x2F;a8174&#x2F;liquidpistons-hyp...</a><p>Edit: citation added
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dietricheppabout 10 years ago
The efficiency is mentioned, but I don&#x27;t see any numbers telling how efficient it is, which is what I really wanted to hear. (Just numbers about how small it is.)
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negativityabout 10 years ago
This is a version of a Wankel Engine, right?<p><a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Wankel_engine" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Wankel_engine</a><p>Originally invented and patented way back in 1929.
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raverbashingabout 10 years ago
A better chance at Darpa than selling it to the doofuses at the big motor companies, where it would certainly be shelved.