A while ago I suggested increasing rocket thrust through the

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they did

>>7664545
link? why did it flop?

The issue is your exhaust has momentum and won't hug the conada surface tightly when its moving at a mach multiple.

Also it's hot, nozzle bells have active cooling.

>>7664656

expensive and very fuel intensive like all early VTOL jet projects. Also had more complicated systems which required expensive computers to control. There's a reason why the F-35 has a glass cockpit

Wings work by pushing air down not bernouli

>>7664456

It was your specific understanding of the Coanda effect we criticized, not the existance of the Coanda effect itself.

In your original thread, you suggested that bending the exaust multiple times would result in effectively limitless thrust. "Bending the exhaust down makes lift, so why not do that multiple times?" But each time you bend exhaust from vertical back to horizontal you lose any lift you had gained by bending it down. You handwaved this away by saying that, "the spike turning the exaust sideways has a smaller radius than the skirt bending it downward," but this has nothing to do with the lift that would be negated or produced.

I don't see any of these details in your post for the current thread. Have you let go of the magic version of the Coanda effect in favor of the real one?

>>7664678
I was in that original thread, and if I may interject, I believe the specific misunderstanding was that the Coanda effect *multiplied* thrust by entraining external air into the exhaust stream, thereby increasing the effective reaction mass. Basically, that the tendency of air to flow along a surface was enhanced if there was already air flowing along that surface.

If this was how the Coanda effect worked, it would indeed do that, even with conservation of energy: If you double the mass flow while keeping exhaust power the same, the flow velocity goes down by [math] \frac{ 1 }{ \sqrt{ 2 } } [/math], and so thrust increases by [math] \frac{ 2 }{ \sqrt{ 2 } } [/math].

So I would disagree that OP is an idiot who can't into basic physics. I think it's more that there was a misunderstanding of the specific aerodynamic effect involved - I found myself thinking that was how it worked for a while there, because some of the pages I looked at seemed to claim that it did multiply thrust this way.

>>7664678
Dont put words in my mouth i never said anything about limitless thrust. So the drawing was flawed, the concept is still sound with modification

>>7664677
>lift at zero angle of of attack
Wings work by a mixture of the two.

>>7664698
As a matter of effect, the Coanda effect *does* do that. It's how those Dyson bladeless "air multiplier" fans worked - a small Coanda-effect jet was blown over the interior of the ring, which (through inducement and entrainment, well-known hydrodynamic effects) caused a much larger mass of air to follow the stream.

The Dyson fans are essentially just the Coanda-effect craft turned inside out. Instead of the jet following the *outside* of a disk with an airfoil-shaped profile, they have the jet follow the *inside* of a ring with an airfoil-shaped profile.

>>7664731
It's also pretty obvious why that would be.

Inducement just means that because there's a stream of fast-moving air going in one direction, this creates a low-pressure zone, so the air behind the stream is also pulled in that direction.

And entrainment just means that because air friction exists, air next to the jet is also accelerated to follow the jet.

The reason OP's idea wouldn't work is different. In order for these effects to work smoothly and not waste a shitload of energy in turbulence, you have to have laminar flow, which means you need a low Reynolds number, which means you need a low flow velocity relative to the viscosity of your fluid. This is exactly what hypersonic jet of rocket exhaust doesn't have. It's just going too damn fast for atmospheric pressure to smoothly stick it to a surface.

>>7664717
>the drawing was flawed, the concept is still sound with modification
This kind of shit is what makes your type of crackpot so infuriating. They post something stupid, get BTFO, make minimal to no acknowledgement of having put forth an utterly ridiculous proposition, and then present something entirely different claiming it's the same thing and they were, at the heart of it, right all along.

>>7664760
>>7664456
In this case, the original proposition was insane, and now you're just splitting hairs over an especially impractical variant of the air-augmented rocket.

>>7664760
It's not stupid it has been done this guy>>7664545 literally posted what I was getting at. I don't see why you are latching onto the fact that I drew it wrong as if that makes it pseudoscience-tier
>>7664731
Oh is that how that thing works? I've always wondered. Clever guy.
>>7664755
Alright fair enough the Avrocar did fail due to turbulence but I don't think Coanda craft are dead in the water there could still be a place for it in modern electric UAVs which have a low flow velocity.

>>7664656
adjustable 'venetian blinds' wings
bad range (no wet wings)
bad radar cross section
limited to ground support

>>7664811
>It's not stupid it has been done this guy>>7664545 # literally posted what I was getting at.

You said the Coanda effect could be used for rockets lifting to orbit.
He posted a picture of a plane.
>See?? I was right!

Your kind is always are "right," because you possess a large enough capatiy for self-delusion that you can always change the definition of "right" to whatever the outcome happens to be.

In this case, you have taken the existance of a trashed airplane program as proof that the Coanda effect would work for orbital launch vehicles.

There is no amount of being wrong that a crazy person cannot reinterpret as being right.

>>7664811
>literally posted what I was getting at

Yes, except it's different in every important way. It's like suggesting that perhaps we could launch orbital vehicles into space by taking balloons all the way up to geostationary orbit, and pointing to stratospheric balloons as proof of concept.

>>7664958
>someone posts an idea
>"ree! deluded nut!
I swear it has got to be the same,dogmatic asshole every time. It was just an idea is there a law against new ideas? are we /catholicism/ now? I never claimed it would work for orbit, I just asked if it would. Why are you so assblasted? You claimed you cant get extra thrust this way so I pointed to the plane as proof. So i admitted my idea was too far out but could,still be good for normal planes and you are attacking me for even this saying im movingbthe goalposts? The SSTO idea was dropped long ago, I never even mentioned it in this thread, this is just about general rocket thrust which could be anything sub orbital which planes can totally achieve. If you are going to be a negative angry asshole just fuck off.

>>7665133
Are you thick? that was to show you can boost lift from a reaction engine using coanda surfaces, i never said that that particular design could get to orbit.

>>7664958
See these guys >>7664698
>>7664755
calmly explained the flaws without being a fuckhead, why could you not do this? are you autistic?

>>7665728
I'm one of the guys you referred to as "calmly explaining the flaws", so I think you can trust that I don't think you're a nut.

So can I just let you know that erupting about dogma, and how people are too closed-minded to respect your brilliant ideas, REALLY isn't doing you any favors? That's the sort of thing that sets off the crank detectors. I know that's probably not what you're trying to say, but it's really how that post comes across.

Also, the lower a rocket jet's speed, the less efficient it is as a rocket. "Effective exhaust velocity" is a critical term in the rocket equation, because it determines how much momentum you can get out of each kg of fuel. Because of the exponential growth of fuel requirements in the rocket equation, even small reductions in exhaust velocity can dramatically reduce fuel efficiency.

So really, trying to use the Coanda effect as a thrust multiplier for rockets in atmosphere just doesn't work. At low enough exhaust speeds that this actually works, there's no point using a rocket at all instead of a jet.

>>7665734

I'm one of the guys who answered like a fuckhead, but truly, my patience with this OP is long spent.

I was in the thread the first time around, and went so far as to draw things in photoshop to better explain why the Coanda effect did not work the way he thought it did, and could not be used to limitlessly multiply thrust.

At the end of that thread, OP had the same condescending overconfidance he's displaying now. His posts turned more and more to, "I'm just *sure* this would work for rockets, and if you don't think so, you must be dumb." And now here we are again going over the same ground, and again OP is interpretting and using all evidence that the Coanda effect exists as proof that it would work for rockets.

In the previous thread, when someone said it wouldn't work for rockets, he posted a picture of a model airplane, treating it as irrefutable proof that his idea was sound.

I tracked down that model airplane, gathered ALL data on it, calculated the thrust of that propeller, with that motor, using that battery, and showed him that it was already capable of lifting the model, and thus, that the Coanda effect was not magical. This was dismissed with a snarky comment. "It doesn't matter when the things I'm putting forth as proof of my idea are disproved, because I'm just sure I'm right!" was the sentiment he did not realize he held.

I'm responding to him like a fuckhead now because he does not respond to calm explanation, to diagrams explainging things gently, or to calculated data with all work shown and sources given. He doesn't respond to any of it, and my patince with him is spent.

I'm responding to him like a fuckhead, because he will not change either way, and at least this way makes me feel good.

>>7664456
I doesn't lift pointing it horizontally, dumbass,