I understand that turbofan powered aircraft can reach much faster speeds than turboprops like the C130 Hercules, and I can't imagine a
turbofan turboprop powered 737 would be of any use really, but as to the logic behind that, I'm a bit confused.
I've read up that a turboprop draws in more air but at a slower speed and a turbofan draws in less air but at a higher speed. But if you have more air in a turboprop, can't you compress it to great amounts, whereas in a turbofan you have less air so you cannot compress as much? And to my understanding (and I may be wrong) the low pressure compressor in a turbofan regulates not only the pressure but the speed of the air, so how is the entry speed of the air relevant to the engine's performance? It just seems a bit counter-intuitive to me. More air = more to compress, but lower speed = less being sucked into the engine per second?
Somewhere online it said that turboprops aren't great at high altitudes unlike a turbofan, because the air gets thinner and the turboprop can't suck as much in then. But then my question is, if a turbofan sucks in less then how does this statement work?
I'm just completely stuck with this at the moment, and I've had a bit of a mindblock. If someone could help me out with this I'd really appreciate it.