2 cylinder, 4 piston, turbo, 2 Stroke

Reminds me of the 8 piston 4 cylinder 2 crankshaft 2 stroke marine diesel that we had in school.
 
Of all the 'new' engines people design that one looks like it may actually have some benefits over what is out there now. It will be interesting to see how they deal with the ring lubrication while meeting emission standards though, piston crown cooling could also be a bit of a challenge.
 
Compared to a 2 stroke, there's a lot of friction in the 2 extra strokes of a 4 stroke.
2 strokes, on the other hand, lose efficiency to their whacky method of crankcase pumping of the air charge.
Both 2 strokes and 4 strokes whare the ineffiiciency of pumping fresh air charge out the exhaust port.

The main benefit of this new design, it appears to me, is that the primary inefficiencies of a 2 stroke - intake charge going out the exhaust port before port closing, and intake flow/energy losses due to the typical 2 stroke's crankcase charge air pumping system, can be eliminated by forced induction made after the exhaust port closes. High pressure direct fuel injection into the combustion chamber adds still more efficiency.
 
Possibly the biggest friction contribution of a 4st over a 2st is the oil control rings, these usually have a pretty high contact force and are narrow so they do not develop any sort of hydrodynamic lubrication (which would reduce friction). Looking at this engine it is almost certain that it will be a wet sump or dry sump much more like a conventional 4st engine so it will also have oil control rings, this design consideration would be almost entirely driven by the need to meet emission standards, burning oil like a conventional 2st makes this very difficult. The asymmetrical port timing is a big advantage although also not new, the Roots TS3 had a similar opposed piston externally scavenged design. Another possible advantage of this engine (maybe, I didn't look too closely at the animations) is the asymmetrical nature of the piston movement will allow energy to be extracted through a larger crankshaft rotation.
 
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