3 Spool vs 2 Spool
unmanned transport
Thanks for your post, it was very accurate and informative.
tuna hp
The real key is not only the compressor rotational speed, but the aerodynamics that is designed into to both blades and vanes throughout the compressor and for that matter, the turbine. Also, don't forget the combustor efficiency, a big part of good, efficient fuel burn. A 3-D highly swept, light weight fan also helps immensely, as much of the thrust comes from the air passing through the fan which by-passes the core engine.
Faster doesn't = fuel efficient as "Bear" pointed out, except the Concorde with its engines were very good.
As I understand it, Rolls Royce is developing two new engines (concepts): One is an open fan design, not unlike the GE36 and the other is an engine that could compete if Boeing carries through on developing a total new replacement for the B-737. This engine is being designed at Rolls-Royce Deutschland Ltd & Co KG, and is a two spool design. This is where their two spool design expertise resides.
As in everything, you have to think outside the box at times to successfully move forward.