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Old 30th Jan 2013, 20:14
  #45 (permalink)  
peter kent
 
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If the airflow feeding what you term the Ramjet "section" of the J58 is isolated from the internal machinery of the turbojet in toto, there would (technically) be a Ramjet "component" to the engine's power. If the source of this air is the compressor section, you are completely, and patently, wrong. I do not care who endorses the definition, Ramjets operate from passive air, not mechanically enhanced air.
I think this makes sense.
Too many classifications add no value . They require explanations. Just say what it is.
Engine A is a dual cycle. What does that mean? Well, above a certain speed it bleeds off some air.
Engine B is a dual cycle. Oh you mean... No! It's got variable stators...
Engine C is like a ramjet at high speeds. Right, that's because.... No It's got a spike like ramjet intakes. Oh, thanks.
J58? Just tell it like it is.

However there is an audience that wants classifications and intuitive 'understanding'.
KJ knew this (Discovery video for public consumption). Why didn't he call it a flow inducer on the program? Wrong audience. He saved that for "Our good friends at Pratt and Whitney do not like us to say that at high speeds their engine is only a flow inducer and that, after all, it is the nacelle pushing the airplane".

Continuing, the inventor actually suggests possible options to the turbojet problem. His "Option 3" he actually labels the "Turbo-Ramjet", which he rejects as too heavy. This option involves bypassing completely the Turbo machinery.
Exactly. He defines what a turboramjet is. He worked in the aero engine industry. He created a world beating engine. He didn't write textbooks or work at a think tank coming up with schemes and definitions that would never see the light of day. Some textbooks had the same definition BTW, eg Hesse and Mumford "jet propulsion for aerospace applications"' written by LTV engineers.

the purpose of the bleed air is to cool the compressor then reinject the bleed into the ejector to be "reheated"...
Don't understand, I'll read again.
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