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Mysterious Sound Waves Can Destroy Rockets

Soulskill posted about 6 years ago | from the scientists-get-the-best-toys dept.

Science 193

Ponca City, We love you writes "Scientists believe that powerful and unstable sound waves, created by energy supplied by the combustion process, were the cause of rocket failures in several US and Russian rockets. They have also observed these mysterious oscillations in other propulsion and power-generating systems such as missiles and gas turbines. Now, researchers at the Georgia Institute of Technology have developed a liquid rocket engine simulator and imaging techniques to help demystify the cause of these explosive sound waves and bring scientists a little closer to being able to understand and prevent them. The team was able to clearly demonstrate that the phenomenon manifests itself in the form of spinning acoustic waves that gain destructive power as they rotate around the rocket's combustion chamber at a rate of 5,000 revolutions per second. Researchers developed a low-pressure combustor to simulate larger rocket engines then used a very-high-speed camera with fiber optic probes to observe the formation and behavior of excited spinning sound waves within the engine. 'This is a very troublesome phenomenon in rockets,' said Professor Ben Zinn. 'These spinning acoustic oscillations destroy engines without anyone fully understanding how these waves are formed. Visualizing this phenomenon brings us a step closer to understanding it.'"

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193 comments

Good news! (5, Funny)

bluephone (200451) | about 6 years ago | (#23032430)

This means rocket science is once again hard. You may now resume saying "Well, this isn't rocket science" until they solve this.

Re:Good news! (3, Funny)

fractoid (1076465) | about 6 years ago | (#23032664)

Bah, this isn't hard. These rockets are just getting speed wobbles, any 8-year-old boy with a bike will be able to tell you all about them!

I've been a member of slashdot for some time (5, Funny)

JeanBaptiste (537955) | about 6 years ago | (#23032434)

and the subject line for this article has finally convinced me that cowboy neal is in fact art bell.

Vibrator?? (2, Funny)

AmigaHeretic (991368) | about 6 years ago | (#23032438)

Is that a rocket in your pocket? Finally I could satisfy a woman! :(

Re:Vibrator?? (0, Troll)

russlar (1122455) | about 6 years ago | (#23032486)

Is that a rocket in your pocket? Finally I could satisfy a woman! :(
Do you even know what a woman looks like?

Re:Vibrator?? (5, Funny)

compro01 (777531) | about 6 years ago | (#23032506)

of course. we've got lots of pictures. =D

Re:Vibrator?? (4, Funny)

AmigaHeretic (991368) | about 6 years ago | (#23033066)

>>>> Do you even know what a woman looks like?

>>of course. we've got lots of pictures. =D

Yeah, and I know all about womens emotions and stuff. Like, chicks HATE it when you call them broads.

Re:Vibrator?? (0)

Anonymous Coward | about 6 years ago | (#23032572)

Is that a rocket in your pocket? Finally I could satisfy a woman!

we're not interested. Thanks in advance,
Women.

Re:Vibrator?? (0)

Anonymous Coward | about 6 years ago | (#23033094)

You just ruined sequence of funnies, asshole.

I can finally be of use to science (5, Funny)

Profane MuthaFucka (574406) | about 6 years ago | (#23032446)

I wonder if they'd be interested in analyzing the smoking ruins of at least 5 toilet bowls I have personally destroyed with mysterious oscillating rocket powered sound waves.

Re:I can finally be of use to science (5, Funny)

Tablizer (95088) | about 6 years ago | (#23032528)

I wonder if they'd be interested in analyzing the smoking ruins of at least 5 toilet bowls I have personally destroyed with mysterious oscillating rocket powered sound waves.

Oh great, Mr. Goatse himself is now posting on slashdot.
       

Re:I can finally be of use to science (4, Funny)

NevarMore (248971) | about 6 years ago | (#23032604)

Oh great, Mr. Goatse himself is now posting on slashdot.


Thats impossible. In order to get a good sound out of that it'd have to be a bit tighter and able to make a good PHHHHHHBBBBBTTT sound. The way Mr. Goatse is now it would just kind of go phooooo. Even then I doubt if there is enough of a seal left to keep it from leaking out long enough to build up sufficient volume and pressure to do anything noticable.

Re:I can finally be of use to science (5, Funny)

PitaBred (632671) | about 6 years ago | (#23032920)

It scares me that you have devoted that much time thinking about the physics of that.

What TFA leaves out (2, Funny)

garett_spencley (193892) | about 6 years ago | (#23032452)

When analyzing the acoustic oscillations scientists discovered something quite striking. The sine wave was exactly identical to the master recording of Britney Spears' "Hit Me Baby One More Time".

Re:What TFA leaves out (0)

Anonymous Coward | about 6 years ago | (#23033042)

Amazing, since it was previously believed that the resonance of those waves could only cause a career to crash and burn.

Nothing new here (0, Offtopic)

EmbeddedJanitor (597831) | about 6 years ago | (#23032496)

The Tacoma Narrows Bridge http://www.youtube.com/watch?v=AsCBK-fRNRk [youtube.com] was essentially destroyed by low frequency sound waves.

Re:Nothing new here (0)

Anonymous Coward | about 6 years ago | (#23033192)

wind?

Somthing Wrong Here. was Re:Nothing new here (5, Informative)

FlyingGuy (989135) | about 6 years ago | (#23033296)

Ok, before parent gets any farther this has to be de-bunked. Sound waves did not destroy the bridge. A sound wave, in any medium consists of a compression and a rarifraction ., that is a leading pressure wave followed by a area of lower pressure that propagate in a known fashion. The intensity of a sound wave obeys the inverse square law.

What happened to the Tacoma Narrows Bride was caused be an error in aerodynamic calculations on the part of the design engineer. Air passing around the bridge deck acted exactly like air does when presented with a crude airfoil, it formed an area of low pressure leeward of the bridge deck and a low pressure area leeward and below the bridge deck. Th resulting high pressure and low pressure vectors imparted a twisting moment to the bridge deck.

The twisting moment was resisted by the torsional rigidity of the bridge deck. This caused the deck to twist to and build torsional tension. The twisting caused the aerodynamic profile of the bridge deck to change. The resulting change allowed the bridge deck to revert back to its original shape and aerodynamic profile, rinse and repeat. Thus the repeated twisting caused enough of the riveted and bolted joints to fail which led to a cascade failure as the remaining joints failed under the bridges weight and twisting motion.

This was not "low frequency sound waves" although the structures oscillations did cause some very low frequency sounds waves, it was destroyed by nothing more then bad aerodynamics.

Re:Nothing new here (1)

interiot (50685) | about 6 years ago | (#23033334)

What uses 0.2hz [vibrationdata.com] waves for acoustic communication? Even an elephant on sulfur hexafluoride doesn't get that low.

No, those are not sound waves (0)

Anonymous Coward | about 6 years ago | (#23033340)

Those weren't sound waves. Waves on a jumprope aren't sound waves and neither were those on Tacoma Narrows Bridge.

Re:Nothing new here (0)

Anonymous Coward | about 6 years ago | (#23033392)

No, it was not. The effect was in reality an areodynamic vortex sheding(sp?) problem.

Defense System? (4, Insightful)

BountyX (1227176) | about 6 years ago | (#23032498)

Could be implemented in a way to defend against rocket\missle attacks? Possibly in a better way than Star Wars program.

Re:Defense System? (4, Insightful)

evanbd (210358) | about 6 years ago | (#23032600)

No. We're talking about pressure waves inside the engine, at pressures measured in tens or hundreds of psi, that resonate with the injector to build power -- think about blowing across the top of a beer bottle. The small power input from your breath induces a higher power oscillation. Same effect, where the bottle is replaced by the combustion chamber and your breath by the injectors. Except the power involved is a hundred million times higher (maybe more, I didn't do the math very carefully).

These waves can't be set up unless the engine will support them, and if it will then they'll happen on their own. If you could deliver that much energy to the engine remotely, you could just as easily destroy the rocket. It's the *resonance* that's the problem, not the fact that there's a crapload of sound energy available.

Re:Defense System? (0)

Anonymous Coward | about 6 years ago | (#23032804)

No. We're talking about pressure waves inside the engine, at pressures measured in tens or hundreds of psi, that resonate with the injector to build power



These waves can't be set up unless the engine will support them, and if it will then they'll happen on their own. If you could deliver that much energy to the engine remotely, you could just as easily destroy the rocket

What about those ultrasonic sound wave inducers that sea vessels use against pirates? (No joke intended, it was on /. a while back). IIRC, they use a directed ultrasonic beam. Could those be used to create resonance inside an incoming rocket engine, or would a frickin' laser beam be more feasable?

Re:Defense System? (5, Interesting)

evanbd (210358) | about 6 years ago | (#23032918)

The laser beam is way more feasible, even if you ignore considerations of range. Not to mention that when a liquid-fueled military rocket is operating, it's going to be either over the horizon or in vacuum -- we're not talking about small tactical missiles here.

We're talking about loud sounds here -- and not just a little bit loud. 1 pascal of pressure wave is 94dB SPL -- a fairly loud sound. 1 psi is 6894 pascals; we're talking about many psi of pressure variation. A 10 psi wave would be 190dB. That's not just loud enough to cause hearing damage; that's well past loud enough to knock over buildings. Overpressure from large bombs is less than that at the edge of the blast radius.

It should be obvious why that's destructive when it happens inside a rocket chamber, especially since oscillations like that tend to start small, grow *rapidly*, and not stop growing until something breaks. It should also be obvious why you won't be able to create such a wave via external influence unless the chamber can already resonate in that mode. When developing the F1 (Saturn V main engine) NASA had trouble with instability; in order to see whether the engine was barely stable or had plenty of margin, they had to find techniques to induce these waves. What they developed, and still use today, is a set of techniques for putting an explosive charge *inside* the engine, bringing the engine up to normal operating conditions (making the charge survive this is nontrivial), and *then* detonating it to see how the engine responded.

Re:Defense System? (1)

RKBA (622932) | about 6 years ago | (#23033208)

So they need to find a shape for the combustion chamber/nozzle that has no single large fundamental resonance frequency, but without sacrificing too much thrust efficiency. It will be interesting to see what sort of shape, or baffling system, they devise. Maybe they could use some of the expertise from the manufacturers of firearm sound suppressors [wikipedia.org] who face similar problems, though less serious and demanding. Although resonance isn't the problem firearm suppressors are designed to address, they do considerably reduce the sound levels as the exhaust gases exit the barrel. Maybe tomorrow's spacecraft will launch with a Paladin Armory [paladinarmory.com] sound suppressor attached to it. ;-)

Re:Defense System? (2, Insightful)

Hojima (1228978) | about 6 years ago | (#23032654)

Almost instantly you can see that it would be very impractical to use sound to destroy rockets. Unless you blast the sound waves constantly, you wont be able to destroy the rockets since they travel much faster than sound (that and air is a terrible medium to transfer the waves through with the Doppler effect hindering it, so they'll never reach the missiles with enough strength). Lasers are still tricky, but there wont be a better alternative to them in the future, when their strength and our tracking systems will be at a prime. Though the best missile defense is undoubtedly diplomacy.

Re:Defense System? (1)

Johnno74 (252399) | about 6 years ago | (#23033164)

Could be implemented in a way to defend against rocket\missle attacks? Possibly in a better way than Star Wars program.
Yeah, all you'd need to do is mount an extremely hardy, remote-controled loudspeaker inside the combustion chamber of every rocket your enemy had.

That sounds WAY more easy than star wars, as long as you arrange it all before they launch.

Actually, maybe there isn't as much in it as I thought.

If you play them backwards (4, Funny)

xs650 (741277) | about 6 years ago | (#23032548)

If you record them and play them backwards they will install Vista on your computer.

Didn't Nikola Tesla talk about something like this (-1, Redundant)

Draped Crusader (1174049) | about 6 years ago | (#23032552)

I remember reading about Nikola Tesla using sound waves to demolish a building or something like that.

Re:Didn't Nikola Tesla talk about something like t (1)

Tablizer (95088) | about 6 years ago | (#23032566)

I remember reading about Nikola Tesla using sound waves to demolish a building or something like that.

Wow, he invented Britney Spears also?
     

Re:Didn't Nikola Tesla talk about something like t (0, Insightful)

Anonymous Coward | about 6 years ago | (#23032656)

well hey, thanks for posting. something you might have heard about somewhere about a subject you very likely have no knowledge about whatsoever. i can guess that by the complete lack of anything useful in your post. let me go way out on a limb here and guess that your age is 14 years or less. 15 tops. in the future, be useful or silent. thanks!

Re:Didn't Nikola Tesla talk about something like t (1)

SiriusStarr (1196697) | about 6 years ago | (#23032868)

While the power of standing waves is well-documented, (see the aforementioned Tacoma Narrows Bridge) this story is commonly considered to be an urban legend, as far as I can tell. They did try it on Mythbusters, though. There were issues with Tesla's designs, so they were forced to build their own. While they were unable to even slightly harm a small-scale model, they did have some success making an actual suspension bridge vibrate. Still, vibration is far from destruction; while much damage to buildings during earthquakes is due to standing waves, in those cases we are talking about faarrrr greater amounts of energy than Tesla's oscillator.

Re:Didn't Nikola Tesla talk about something like t (0)

Anonymous Coward | about 6 years ago | (#23032906)

The point of Tesla's experiments were that you didn't need a huge amount of force, just a small force at just the right frequency for the particular object. The small oscillations would reinforce the previous ones and grow into a more powerful force that eventually cause collapse... Even mythbusters gave this a plausible.

Re:Didn't Nikola Tesla talk about something like t (1)

SiriusStarr (1196697) | about 6 years ago | (#23032948)

Of course. I never denied the theory behind it, and I do know they listed it as plausible (see "some success making an actual suspension bridge vibrate"). My point is simply that Tesla didn't actually destroy a building. He simply showed that it is theoretically possible.

Re:Didn't Nikola Tesla talk about something like t (2, Informative)

GuNgA-DiN (17556) | about 6 years ago | (#23033014)

From the New York World-Telegram -- July 11, 1935:
http://www.rastko.org.yu/rastko/delo/10896 [rastko.org.yu]

[Nikola Tesla:] "I was experimenting with vibrations. I had one of my machines going and I wanted to see if I could get it in tune with the vibration of the building. I put it up notch after notch. There was a peculiar cracking sound.

"I asked my assistants where did the sound come from. They did not know. I put the machine up a few more notches. There was a louder cracking sound. I knew I was approaching the vibration of the steel building. I pushed the machine a little higher.

"Suddenly all the heavy machinery in the place was flying around. I grabbed a hammer and broke the machine. The building would have been down about our ears in another few minutes. Outside in the street there was pandemonium. The police and ambulances arrived. I told my assistants to say nothing. We told the police it must have been an earthquake. That's all they ever knew about it."

Watch Out, Mr. Smith

Some shrewd reporter asked Dr. Tesla at this point what he would need to destroy the Empire State Building and the doctor replied: - "Five pounds of air pressure. If I attached the proper oscillating machine on a girder that is all the force I would need, five pounds. Vibration will do anything.- It would only be necessary to step up the vibrations of the machine to fit the natural vibration of the building and the building would come crashing down. That's why soldiers always break step crossing a bridge."

And then... (2, Funny)

adona1 (1078711) | about 6 years ago | (#23032564)

Dr No will fish them out of the water and pass the rockets on to SMERSH....I don't like the sound of that!

Summary is a bit off (5, Informative)

evanbd (210358) | about 6 years ago | (#23032568)

The new result here isn't acoustic instabilities; those have been known for a long time. The interesting result is a new set of imaging techniques that give a better understanding of *why* they occur, rather than simply observing on pressure traces that they *do* occur. After a bit more research, this may turn into techniques to more reliably avoid them in the design stage, rather than having to go through various tweaks on the injector / combustion chamber to remove them should they appear.

This is very cool work. Of course, it's rocket science, not rocket engineering, so it's unlikely to impact new designs for several years yet.

Re:Summary is a bit off (3, Interesting)

Nefarious Wheel (628136) | about 6 years ago | (#23032680)

A problem with dealing with acoustic resonance is just how to manufacture the rocket nozzle to avoid the buildup of these dangerous resonances. Modelling them is the first step, but how can you build the nozzle with sufficient strength while building in structure to interrupt the phase of the wave repeats? Experimentation is a lot cheaper when you can simulate the results. I could imagine moving to non-round shapes might solve the problem, or heterogenious structures - possibly by introduction of dissimilar materials in the bell, perhaps a strapped interspersion of titanium and stainless? I wonder how difficult that could be to model.

Or I could be full of crap, which is also a distinct possibility.

Re:Summary is a bit off (4, Informative)

evanbd (210358) | about 6 years ago | (#23032968)

No, you're on the right track, but not quite there. Computational techniques are only barely able to simulate rocket chambers well; combustion dynamics are complex and not well understood. That's a large part of what makes this work interesting (the other part being the imaging techniques to actually photograph the waves).

The problem isn't actually the chamber or nozzle walls resonating, it's the acoustic cavity -- exactly analogous to an organ pipe. There are a variety of techniques used to de-tune the resonance modes. (It also happens in the chamber, not the nozzle -- gas in the expansion portion of the nozzle is locally supersonic, so sound can't propagate backwards, which means no resonance.) For example, the SSME has some of the injectors protruding further into the chamber than others, creating interruptions in the flat surface of the injector face. There exist other techniques, and some google searching will turn up some. Also, playing with the metals in the chamber wall is probably right out -- they're basically already decided by thermal considerations, and high performance engines almost universally use copper.

Historically, the design process has involved experienced engineers, rules of thumb, and lots of testing. Computer models will help, but they'll never really replace the "lots of testing" stage. At least for small engines (up to several thousand pounds of thrust), it's cheaper, easier, and more accurate to just build the thing.

Re:Summary is a bit off (0)

Anonymous Coward | about 6 years ago | (#23033292)

High performance rocket engines use copper combustion chambers b/c of thermal considerations? Why not titanium (melting point of ~1900K > copper's at ~1350K)? Or even just steel, since the chambers are regeneratively cooled anyway, iirc?

Weapon (2, Interesting)

MrGHemp (189288) | about 6 years ago | (#23032612)

I can't help but wonder if understanding this won't lead to some powerful weapons... think about it a sonic cannon, that might make some interesting CNN coverage during war time.

Missile defense? (1)

Laughing Dog (913885) | about 6 years ago | (#23032676)

So is gangsta rap going to be the new missile defense? Instead of dedicated stations, we could have a volunteer rapid response unit consisting of Honda Civics.

More importantly (1)

game kid (805301) | about 6 years ago | (#23032796)

...will the Civics play Soulja Boy, and will "Superman that" be slang for attacking an incoming warhead?

Misprint (0)

Anonymous Coward | about 6 years ago | (#23032696)

Should read:
and bring scientists a little closer to being able to understand and generate them.

Interesting (1)

mjaworsk (1271170) | about 6 years ago | (#23032698)

I wonder if these sound waves might be put to good use... such as setting off a series of timed explosions creating a "traveling wave" that induces rotation... This might come in real handy if, say, the core of the earth were to stop spinning for some reason... hmmmm... oh crap, this justifies a terrible movie.

Turn it inside out. (5, Interesting)

camperdave (969942) | about 6 years ago | (#23032748)

Rocket engines typically have a round cross section, which, if it doesn't aid the production of these circular waves, probably does little to dampen them. I wonder if the "inside out" design of a linear aerospike engine [google.com] suffers from the same problem.

Re:Turn it inside out. (3, Interesting)

evanbd (210358) | about 6 years ago | (#23032980)

Aerospike engines still have an enclosed chamber; it's only the nozzle that's been changed. The chamber is where the problems occur, not the nozzle. The odd chamber shapes certainly make things complicated, but I have no idea whether they hurt or help overall. The usual technique to get rid of these involves various ways to de-tune the engine -- for example, some of the SSME injectors protrude deeper into the chamber to interrupt the otherwise flat injector face.

Re:Turn it inside out. (0)

Anonymous Coward | about 6 years ago | (#23033046)

If the reason why has more to do with closed chambers than symmetry, probably so. However, that leads to the interesting question of whether an annular aerospike would also suffer in similar ways.

Repeat after me (0)

Anonymous Coward | about 6 years ago | (#23032784)

Sim-harmon-mosh :) You had to be there around '93 to get it.

Look, I can see science media dumbing it down (1)

onion_joe (625886) | about 6 years ago | (#23032798)

for the masses, but this is unacceptable! "Acoustic" waves? Puhhhhhhllleeeezzzzzzzzzzz. High temperature pressure waves in a gas medium constrained by a metallic cone is the proper description.

For crying out loud (sorry;) we are talking ROCKET SCIENCE HERE!!!!

Re:Look, I can see science media dumbing it down (2, Insightful)

Forbman (794277) | about 6 years ago | (#23032908)

pressure waves...acoustic waves... Hmm... I'm having a hard time seeing the difference. I think they use "acoustic" because of their frequency is probably between 20Hz-20KHz... otherwise known as "acoustic".

I'm wondering if the waves are just something related to how the energy goes out at such high pressures and it being a bit opposite in how the soda bottle "vortex generators" work. Pressure is high enough so that all the fluid flows out axially instead of rotating around the axis to some degree, but these rotating acoustic waves are just a form of conservation of (angular) momentum in the fluid flow that under less pressured circumstances would want to make a vortex?

Dr. No (1)

breadlord (827860) | about 6 years ago | (#23032806)

Yeah, yeah, we've been through this before. Dr. No, evil genius with his own Caribbean island, guano empire. Bond on the beach with Honey Rider, bang-boom, no more "interference" with our rockets. Guess we throw the Russkies a bone on this one, in the name of our newfound cooperation.

Pogo Oscillations (4, Interesting)

orospakr (715849) | about 6 years ago | (#23032808)

This phenomenon sounds very similar to Pogo Oscillations, which incidentally caused the engine 5 shutdown on the Apollo 13 Saturn V.

  http://en.wikipedia.org/wiki/Pogo_oscillations [wikipedia.org]

Re:Pogo Oscillations (3, Informative)

evanbd (210358) | about 6 years ago | (#23033030)

Similar, but different. Both are oscillations, but pogo is characterized by low frequency variations in chamber pressure coupling through the thrust structure and into the propellant feed system (and from there back to the chamber pressure). These are high frequency (kHz, no tens of Hz) acoustic modes, contained entirely within the chamber. They're much harder simulate and much harder to get rid of, and much less well understood. They couple from local chamber pressure to the injectors, and operate much like an organ pipe.

Energy? (0)

Anonymous Coward | about 6 years ago | (#23032832)

Could this exploding power be used to generate power?

Re:Energy? (0)

Anonymous Coward | about 6 years ago | (#23033048)

Yeah, but just the one time.

"Strange wave phenomenon" = resonance (1, Informative)

Anonymous Coward | about 6 years ago | (#23032834)

The summary makes it sound like this is a new and mysterious phenomenon. It isn't.

Resonant frequencies inside the fuel pumps and associated plumbing is one of the major problems of getting a real rocket engine run in a stable cycle. This is a 50-year-old problem. There are also 50-year-old solutions, mostly involving re-shaping the plumbing so that resonances are dampened.

See also Pogo oscillation [wikipedia.org] and the famous case of Apollo 13 [wikipedia.org] .

Re:"Strange wave phenomenon" = resonance (3, Informative)

evanbd (210358) | about 6 years ago | (#23033000)

Pogo, pump-related oscillations, and plumbing related oscillations are all low frequency (tens of Hz, sometimes less). These are acoustic modes internal to the chamber, in the kHz range. They're very distinct phenomenon, with distinct causes and distinct solutions. They're still a 50 year old problem with 50 year old techniques to solve them, but they're by no means understood in any meaningful sense -- the current technique mostly involves testing the engine and then tweaking it until they go away.

The new and interesting work here is the modelling, combined with the photography techniques. Seeing pressure waves at the injector face through the chamber full of flame is not trivial.

hmm (1)

thatskinnyguy (1129515) | about 6 years ago | (#23032836)

Doesn't everything have a frequency at which it breaks? I mean, human rib cages, crystal glasses have been known to break with just the right tone. In the case of a former engine of mine (non-rocket), it was right around 133Hz (8000rpm/60seconds=133 Cycles per second).

Wierding Modules? (0)

Anonymous Coward | about 6 years ago | (#23032872)

I can now revive my hopes having a wierding module...and that my name will be a killing a word!

'Cisco-- (1)

ciscoy2g1 (715647) | about 6 years ago | (#23032874)

This is amazing. It's incredible how the accoustics of a barrel can make the physical state of a metal to something that's entirely unknown because it is being bombarded with such energy that it is entirely unknown. The heat radiation that it gives off, as well as the amount of energy released as light, those waves are just bouncing off. Of course, I surely don't mean that it may be a complete possibility, but we simply don't know. What if a total chaotic environment throws off the marks of physics once more to a completely different level, the sound spectrum, the beyond. String theory is portrayed as strings or strands of energy in acoustic resonance with itself, or not, some are broken, making some sounds as neutral. Maybe I'm getting off track here. Whatever, this is all new, so let's begin!

The Sound Village Ninjas (oh no!) (1)

prajjwal (965508) | about 6 years ago | (#23032880)

I know, its the sound village ninjas from Naruto upto their old tricks again!!!

Addicted to bass... (3, Funny)

roxtafari (1256480) | about 6 years ago | (#23032910)

Looks like an audio engineering issue. While not being a rocket engineer myself, I assume the combustion chamber is somewhat symmetrical. It is likely acting as a resonance chamber and increasing the amplitude of the soundwave to the point of physical damage. I shattered the rear window in my '96 Camaro twice with a 1200W Fosgate and a single 10" bazooka tube. Tell NASA to crack the window when they turn up the bass!

Tell me about it... (1)

DamienRBlack (1165691) | about 6 years ago | (#23033060)

Whenever my x-girlfriend started singing, it would destroy my rocket, she had a voice like a crow. Wait, that isn't what we're talking about is it?

Anonymous Coward (0)

Anonymous Coward | about 6 years ago | (#23033072)

Houston,
Whats the story on the center engine cutoff?? ...(beep)...

How simple can this be? (1)

Whiteox (919863) | about 6 years ago | (#23033102)

All you've got to do is to wrap the rocket in sound deadening materials - or negate the sounds by amplifying the same sound out of phase.
What's so hard about that?
Rocket science.... Hrumph!

Muad'Dib (0)

Anonymous Coward | about 6 years ago | (#23033116)

We Fremem have known the secret Bene Gesserit ways of harnessing destructive sound waves for centuries.

"My own name is a killing word. Will it be a healing word as well?" - Paul "Maud'Dib" Atreides

These killer sound waves come in really handy when some obese Harkonnen swine tries to make off with YOUR spice!

More technology to misuse (1)

SEWilco (27983) | about 6 years ago | (#23033132)

"excited spinning sound waves" sounds like something which will be sold next year to the owner of the car ahead of us.

What does sound have to do with it? (0)

Anonymous Coward | about 6 years ago | (#23033134)

Honest question. Isn't sound merely an organic perception of certain frequencies of vibration? Talking about sound waves seems to only make sense in the context that it affects the ear. I assume these rockets broke apart due to intense vibration, not the particular noise that was being made.

Combustion instability is an old problem (3, Interesting)

Animats (122034) | about 6 years ago | (#23033238)

Combustion instability is an old problem with rocket engines. The Saturn V main engine had serious combustion instability problems, which were fixed by trial and error testing. The Apollo booster people had to resort to setting off small bombs inside engines on test stands to induce instability, then trying different patterns of holes in the plates the distributed fuel to find a stable configuration.

The SR-71 engine had serious combustion instability. That, too, was fixed with something of a hack, an automated "sympathetic unstart" system which, when one engine had a stall, would stall the other one, then restart both.

Better simulation tools in that area can't hurt. Not many big supersonic engines are designed any more. As Scott Crossfield pointed out just before he died a few years ago, every aircraft that went significantly over Mach 3 is now in a museum.

My 2 cents (1)

borat4president (1083997) | about 6 years ago | (#23033270)

Talking of rockets and waves, I was at the launch pad at the Baikonur cosmodrome on Tuesday and our crew almost got arrested for using Motorola walkie-talkies. They told us we had been interfering with telemetric systems and the live TV feed from the rocket.

I Call It The "Dutch Oven" Effect (1)

Skeetskeetskeet (906997) | about 6 years ago | (#23033272)

Farting in an enclosed area under a quilt will result in the almost immediate destruction of any relationship.

Master Blaster (0, Offtopic)

Doc Ruby (173196) | about 6 years ago | (#23033330)

"Mysterious sound waves" like years of speeches by a lying president who cancels NASA programs, lies about a Mars mission, and instead converts NASA to Star Wars "missile defense"?
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