Comment by direwolf20
Comment by direwolf20 7 hours ago
Is this not... a propeller? A turboprop engine?
Comment by direwolf20 7 hours ago
Is this not... a propeller? A turboprop engine?
> the distinction is that the blade tips in these reach supersonic speeds like in turbofans
Commercial engines are not designed to have anything to supersonic.
Sorry, you’re correct. You want to avoid supersonic tips as much as possible.
Modern turbofans permit supersonic tips during high-thrust regimes. (Part of the work in these new designs is releasing that constraint since those supersonic tips are a bastard.) It’s something sought to be avoided. But not at all costs at all times.
I’m not an expert but I think the distinction is that the blade tips in these reach supersonic speeds like in turbofans. That is a hard problem to fix because you don’t have the duct to contain the noise and catch the blades if one were to break.