I think I saw this exact design years and years ago in Popular Mechanics. GE's UDF reminds me of it too. https://en.wikipedia.org/wiki/General_Electric_GE36

IIRC, ducted fans are almost always more efficient than open fan designs. It's curious the Celera 500L doesn't use a ducted fan along with a propeller specifically-optimized for such a configuration. (It's an ICE, not a turboprop.)

Unpopular opinion: We need to get away from FF motors, turbines, and airborne transportation unless they can be made GHG negative.