A Radical New Engine Shows Why Internal Combustion Still Matters

[question everything]

I don't know the first thing about auto mechanic but thought someone here may be interested.

============

Reports of the death of the internal combustion engine have been exaggerated.

(snip)

A century-old engine, reinvented

Alexander Shkolnik is founder of LiquidPiston, a company attempting a nearly impossible feat: developing a liquid-fuel-powered alternative to the traditional piston engine. He says his company has cracked the problem, at least for limited applications.

The key is the rotary engine. Unlike a traditional gasoline or diesel engine, it has no pistons. Instead, it has an oddly shaped chunk of metal at its heart, spinning inside an oblong chamber in which the usual cycle of compression, combustion and exhaust takes place. LiquidPiston’s engine can run on everything from diesel to jet fuel, while being a fraction of the size of a comparable diesel engine, and up to 30% more efficient than a comparable gasoline one.

Shkolnik and his team didn’t invent this. The first rotary engines were pioneered in the late 1800s by French and American inventors, and made their way into early motorcycles and airplanes. In the 1950s, German engineer Felix Wankel updated the concept to include the spinning triangular rotor. LiquidPiston calls its engine an “inside-out Wankel” to acknowledge the commonalities.

The U.S. Army and Air Force are both watching. Over the past decade, the Defense Department, including its cutting-edge research-funding body Darpa, has pumped tens of millions of dollars into the company. Whether LiquidPiston’s engine is up to snuff as a portable power station for front-line troops will become evident by sometime next year. That’s when the Army should have results from tests of the latest prototype, says Matthew Willis, director of Fuze, the Army’s new venture-capital-style funding body.

LiquidPiston’s rotary engine is also suited to powering long-range hybrid drones, says Shkolnik. The company built and flew a prototype of one such drone, in which batteries power the vertical takeoff and the rotary engine takes over for long-range horizontal flight. The company is now working on a second, updated version for the Air Force. The hope is that eventually such a drone could fly farther and run quieter than one powered by a piston engine.

More..

https://www.wsj.com/business/autos/rotary-engines-liquidpiston-f055e6fb?st=1HwyCK&reflink=desktopwebshare_permalink

free

[bucolic_frolic]

1. Wankel Wankel been around a long time.

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

I've not advanced past the stage of trying some molybdenum additives in motor oil.

[mitch96]

2. My girlfriend had a Mazda RX 7 that was powered by a Wankel engine. Kinda turbine like sound

Wankel engines are hard on seals that the rotor uses to seal combustion chamber.
Suzuki also had a motorcycle that was a Wankel.. If anything went wrong with it they just replace the whole engine..You got a new one and .Sent the bad one back to Japan. I've heard of development of a Wankel/hybrid concept also...
m

[Old Crank]

3. A version of the wankel

A couple of friends had mazdas when they came out with teh wankel engines.
Smooth running but thirsty for their size. Power output was good also but you were firing like a six cylinder.

I don't know how long they lasted.

They could make sense for long range drones because of the power to weight ratio should be good.