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- How do turbofan nacelle lengths compare? 2 answers
One thing that is plainly obvious about the design and configuration of jet airliners is how little they tend to differ.
It's surprising then that even on the same airliner, you will see two quite different-looking engines.
I've seen A330s with "fully-enclosed" engines, and "open" engines:
(Trent 700 with exhaust mixer, image from Wikipedia).
(PW4000 with unmixed exhaust, image from Wikipedia).
The fact that both designs are used suggests that one isn't simply better than the other, but the difference seems fairly significant.
Why would an engine designer or a customer opt for one design over the other, and why do they arrive at such apparently different solutions for the same use-case?
I assume, perhaps incorrectly, that each has its own advantages and that for whatever reasons different manufacturers and customers value different ones.