You call that a Ramjet? THIS is a Ramjet! (Do 217 with Sänger Ramjet)
Posted Jul 13, 2018, 10:20 PM UTC
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What do.
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zoom
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that's the cannon shell
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So that's where Blofeld got his Spaceship-swallowing rocket from.
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That picture seems inspected by this situation.
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This is what that Top Gear episode would’ve looked like if they’d been asked to turn planes into camper vans instead.
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So when will this be added?
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I'd love some really experimental aircraft in thr game.
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Gaijin, Me 410 with MG213 when?
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[deleted]
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The dornier is actually the parasite here.
in actuality I can probably assume it only produced the equivalent thrust of one of its engine
Apparently the ramjet in the photo produced 20,000hp, which sounds impressive, but horsepower isn't a very good way to measure jet engines.
Assuming typical ramjet exhaust velocity of ~mach 3, it would only produce ~17kn of thrust, or about the same as the two Jumo 004s on the Me 262.
Each engine on the Do 217 would, as best I can figure, produce ~16kn, so if my math is correct, then your assumption is also correct.
How does one measure that? I get a feeling that was dug out of someone's butthole. Ramjets work better the faster you go until it melts from pouring too much fuel in it, so it's not quite top-end speed limited. There isn't a shaft to measure horsepower from either, just the pylon force it exerts on.
Those were tested with an initial supersonic speed I'm fairly sure. A Do 217, well, does it like supersonic flight?
Also, by "only" I was refering if they basically dumped a shitload of fuel with the oversized casing pre-heated to facilitate the expansion and consistant ignition near the 217's top end speed. Which I'm fairly confident that it won't last long.
Horsepower is a measure of power. Power is the rate of doing work, or energy transfer. A jet engine accelerates mass, and thus does work. Thus we can use the following basic equations:
d=vt \ w=fd \ p=w/t
To derive the equation:
p=fv
That is, power equals force times velocity. Take for example a turbofan with an exhaust velocity of 250m/s, and a thrust of 100kn. That gives us 25,000,000 watts, which is about 33,500 horsepower.
And this isn't something I've just made up, propulsive power of a thrust engine is a concept that dates back at least as far as Hermann Noordung's 1929 contribution to rocket science.
A jet engine's exhaust velocity is largely independent of it's operating velocity, aka airspeed. Or are you proposing that a jet engine fired on a test stand has an exhaust velocity of zero?
Now granted, the ramjet does rely on incoming air to operate it's compression, and thus it's thrust will vary by airspeed quite a lot. But it's exhaust velocity will remain about the same across most of it's operating range.
A ramjet can operate at speeds as low as mach 0.13, or as high as mach 6, though typically won't produce near full thrust below ~mach 0.5 due to low compression, and will struggle to overcome drag much above mach 3.
Nonetheless, the Do 217 testbed was able to reach 720km/h (mach 0.63 at 5700m) which is inside the ramjet's comfortable operating range.
For subsonic aircraft yes, but ramjets reach peak thrust at around mach 2.3, yet have been operated at mach 3.3 in practice, meaning they went fast enough to start working less better.