The problem you (and others) have, is in perception of the engine.
The engine isn’t a core with “glued” bypass as many of you apparently think, but is a profile (a bore) of which some percentage of airflow goes through a core and some through bypass.
Take a look at J79 and F100 engined F16 and comparative top speeds, which is a subject here for those who missed it.
I’ve noticed this kinda thing many times over, but I can understand that since you look at the engines linearly and in your book the turbofan is a turbojet with bypass, which it isn’t.
Ramjet is a turbojet without a “turbo” part, though.
I bet you’ll ask me why now, won’t you? 😀
Whilst the F100 is a bypass (fan) engine, the J79 is a turbojet. The reason for using a fan engine for a fighter is that it gives you a better sfc (and less thrust) than a comparable turbojet and still a higher thrust when reheat is applied. Because the air is cooler in a fan engine the percentage of thrust increase with reheat is far higher before it encounters buzz or thermal limitations. There are however difficulties with mixing the air in the reheat pipe
Bypass air does not cool the turbine. If you look closely at the sectioned drawing you’ll see it does not come into contact with the turbine otherwise it wouldn’t be a bypass engine, it would be a twin spool. Compressor air is used (in general high stage)to cool the turbine, even Avons had that so it’s not just bypass engines.
I find it interesting that you quote MigL as being unknowledgeable about gas turbines. He might not use all the correct terms, but what he says is essentially correct. Perhaps you should read a few books again, or listen to someone who actually knows haw a gas turbine works.
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