Does Rocketry Work beyond Earth's atmosphere?

[patrix]

This guy does an experiment to prove rockets work in vacuum
https://youtu.be/uf6158lBjGo

[hoi.polloi]

This guy does an experiment to prove rockets work in vacuum
https://youtu.be/uf6158lBjGo

full link: http://www.youtube.com/watch?v=uf6158lBjGo

And fails to prove that rockets work in infinite vacuum. All this experiment shows is that a propulsion can destroy a vacuum scenario by activating. I would like to see an experiment showing that rocket propulsion works in an absolute vacuum that can take on a great more many changes.

There is no infinite vacuum in a tiny pressurized or depressurized chamber where propulsion is changing the conditions.

If you'd read this thread or actually shown that you've used your brain and not borrowed official stances in thinking about this subject, you might have already noticed this argument and its failure to address the problems.

Now regardless of all the vacuum discussion (and perhaps to save you from this and other equivocating you are doing on the forum) why would you be arguing for the lying scam agency? Your presence is growing tiresome and you're not adding anything to the discussion except a rather useless baseless belief in liars.

[hoi.polloi]

The comment section of that video does contain the classic gems of either side, which basically go something like this:

Doubter: Why is NASA lying?

Believer: It's not just NASA lying. It's many organizations around the world backing up NASA's stories.

Doubter: Let's not change "lies" to "stories". You still haven't addressed the fact that NASA has lied about its space missions.

Believer: (plugs ears) la la la la la

Doubter: Okay, that's not really an argument.

Believer: My dada works for NASA* and he would never lie.

Close curtain

* substitute for:
- I've had military training
- I've looked in a telescope
- I've watched a lot of television
- etc.

[hoi.polloi]

This comment in that video seems to make a bit more sense than the palaver offered by patrix so far:

So, yes, the nozzle opens at the bottom. Completely. There may be steering vanes or shutters (like the German V1 pulse rocket) or platinum catalytic grids, etc, but, yes it's open to space. If you look at videos of rockets being fired

... if you start from NASA's videos, you're already in for brain hurt from having to justify and explain how special effects are real photography. Luckily, that's already happened to this (possibly brain damaged?) fellow.

the combustion plume comes from inside the nozzle and goes out beyond the nozzle opening by some considerable distance

perhaps 5 to 50 X the length of the entire motor. What are we looking at?

Indeed. What are we looking at? Here's this salesman's take:

a bunch of burning rocket fuel rapidly exiting through the nozzle opening.

... and combusting in open space as well as it has in atmosphere, while remaining just as effective and orderly and shaped as if it were operating in atmosphere!

It is a very highly dense, pressurized plume of burning gas stuck right on the end of the nozzle, and in fact the external burn is part of the motor system.

Right, that's what the graphics depict, but would it happen in real life and would it remain effective? Faked evidence does not make it so.

Just looking at the rocket you're holding in your hand you'd think that all of the fuel would just dump out with no effect.

Uh, really?
That's what we would think? He doesn't seem to understand the arguments of his intellectual opponents.

In reality, every new inch of thrust generated exits the nozzle and quickly expands giving a massive cloud of combustion material to push against.

Yes, it quickly expands to ... a nice shapely cone, because hand waving NASA reason.

I wonder why he's chosen inches. Just a turn of speech, I suppose. Like "screaming" fuel he mentions later ...

This accounts for much of the efficiency of the rocket, but most of the thrust is from the rapid burning of the fuel sending it's mass quickly to the exterior. We do have conservation of momentum where M1*v1 (plume mass) = M2*v2 (spacecraft mass). I'm not ignoring you, am writing an appropriate response to your question, if I thought you were in a hurry I would have just sent you an insult.... Feel free to write back with any other questions. I carefully picked these white papers I sent you as they describe operation in layman's terms but also includes the calculus based derivation so you can easily compare one paper with the next. I have to admit, I found no papers or discussion on the open web or the tech subscriptions about the derivation and formulae you are using. Perhaps I need to refine my search? So, you make some accusation that I don't understand how the earth's ambient air causes something or other or not?. Go back to the equation:

F = q * Ve +( Pe - Pa ) * Ae

Where F=Force generated by the total motor thrust q = mass flow in motor Ve = Ejection speed Pe = Ejection pressure Pa = Ambient air pressure (0 for space, 15 psi sea level) Ae = Exit area Pe is very large compared with ambient air Pa. Ae is very large compared with ambient air Pa So, Look at the term (Pe-Pa) and note that there is very little change in thrust from sea level to space. Look at the term (Pe - Pa) * Ae, there is very little effect of having the earth's atmosphere present or not! In fact, the motor will operate a very little bit better in space, ceteris paribus [other things equal].

Funny moment.

The video comments above this lengthy and ineffective argument refer to this old link as an "answer":

We know, the rockets in space use Newton's 3rd law to increase their velocity and hence move. What I don't understand is how it is possible in space aka vacuum-state without air? From what I know, Joule's "Free Expansion of Gas" says that free-expansion compresses the gas and is therefore "affected" by vacuum so it can't make the rocket move as the gas will have zero press/force. Could someone please explain me how rockets do really work and the above-mentioned statement?

Actually, please have a look at this site: http://cluesforum.info/viewtopic.php?f=23&t=1632

Not: The site appears to include some conspiracy theory thingummies, but made me wonder anyway.

-http://physics.stackexchange.com/questi ... ion-of-gas

This thread!

---

This entire discussion is old news, patrix. It's failed. As you browse earlier posts in this thread, you'll see we are still rather cutting edge for posting these questions, and NASA still hasn't come up with a better response than defending and arguing from their fake videos. Now, why would that be I wonder?

Could it be because their best "argument" is ... fake evidence?

[patrix]

All this experiment shows is that a propulsion can destroy a vacuum scenario by activating. I would like to see an experiment showing that rocket propulsion works in an absolute vacuum that can take on a great more many changes.

I agree. And I also agree that NASA and the other space agencies are lying through their teeth about everything, but as I said, I'm interested in finding out the extent of the lie.

And I know science, especially medicine and physics, have been poisoned ad absurdum throughout the 20th century. But I still believe the scientific method works:
I observe something and set up an hypothesis and to try to disprove it by controlled experiments. If I perform a sufficient number of experiments that all fails to refute my hypothesis, the hypothesis holds. If it is not possible to design experiments to refute the hypothesis, I'm out of luck. Then you have to use other tools to figure things out.

For example: Since NASA is lying on just about everything, I set up the hypothesis that rockets don't work in vacuum. I perform an experiment that others can repeat and discover that rockets seem to work in vacuum. If others can repeat the experiment to confirm my findings, then the hypothesis should be considered refuted.

Of course the design of the experiments is of importance. This only shows that a rockets work in a confined vacuum. But since the title of the thread was "Does Rocketry Work in the Vacuum?" I figured this experiment would be interesting. I don't know anything about how the video was made and I have not verified this experiment myself.

Edit: A comment to the other things you write hoi: Yes of course this experiment is made by a true believer in all the space fakery, but I still think it is an interesting experiment. Lets not do the discredit by association thing.

[hoi.polloi]

Of course. Well, when we and legitimate scientists can rent one of those giant vacuum spaces we've mentioned earlier in the thread, we can actually conduct things that barely approach experiments close to what NASA proposes happens in space. Even that would not be right because we would need to get above and stay above the Karman line.

Unfortunately, following developments in real science is tricky because we must train people to also be skeptical of so-called "peer reviewed" massively accepted lies. Do you really believe you are helping people do that with your present contributions to this thread?

In any case, I would appreciate your eye on subjects where you can actually help.

[Flabbergasted]

You are completely missing (or avoiding) the point, patrix. In order to be propelled, rockets must transfer energy to an external medium which offers some degree of resistance. Experiments in vacuum chambers, even huge ones, provide such a medium (the walls of the chamber). The void of space does not. This has been expounded over and over in this thread, if you´d care to read it.

[patrix]

You are completely missing (or avoiding) the point, patrix. In order to be propelled, rockets must transfer energy to an external medium which offers some degree of resistance. Experiments in vacuum chambers, even huge ones, provide such a medium (the walls of the chamber). The void of space does not. This has been expounded over and over in this thread, if you´d care to read it.

Well if the hypothesis that rockets do not work in vacuum can only be refuted by an experiment performed in an infinite vacuum then I guess we're out of luck. Maybe you could put sensors on the walls of a big vaccum chamber to see if anything happens there when the rocket moves?

[hoi.polloi]

Yes, refer to the title of the thread.

"Does Rocketry Work in the Vacuum?" Rather than a vacuum.

[Flabbergasted]

Maybe you could put sensors on the walls of a big vaccum chamber to see if anything happens there when the rocket moves?

It´s not that "something happens to the wall when the rocket moves". A rocket will move in a vacuum chamber (or any chamber, for that matter) because the exhaust bridges the space between the nozzle and the end wall of the chamber, pushing against it. No experiment is necessary to understand that.

[molodyets]

I might not have spent the sufficient time to go through all the comments on this thread, but from the hours I did spend, I do not think anyone has properly explained the free expansion idea. This concept has been incorrectly used to claim that rockets cannot work in a vacuum. I am not, however, giving nasa any credibility.

To understand the concept of free expansion, the situation needs to be viewed molecularly, at the boundary of the compressed gas and the vacuum. At these boundaries, 1 side faces the other gas molecules and the other side faces the vacuum. When a molecule bounces off another, in the direction of the vacuum, it flies off into space. For elastic collisions, then no energy is lost and hence no work has been performed. This process will continue, until all the gas has been dispersed. The big but in all of this, is that with rocket propulsion, there is only a limited space (haha) where free expansion is happening. Therefore, this concept cannot be used to discredit rocket propulsion theory in a vacuum.

In a vacuum, if one side of a container is opened and gas is being expelled, there will be a pressure difference between the closed side and the opened side. The acceleration of the container can then be calculated by the momentum of the escaping gas. If the same situation is performed in a fluid medium (gas/liquid/fluidized bed...) there are so many other factors to take into account. That situation is not as simple. A significant difference in a fluid medium is pressure of the medium. In a vacuum, this is zero. If the pressure is greater than zero, it might aid in the propulsion which could explain the decreasing thrust at higher altitudes. This cannot be extrapolated to zero....

[Flabbergasted]

I think you got it wrong.

To understand the concept of free expansion, the situation needs to be viewed molecularly.

The trendy word "molecularly" adds nothing new to the discussion.

For elastic collisions, then no energy is lost and hence no work has been performed.

That is a bit hazy. Would you care to explain?

The big but in all of this, is that with rocket propulsion, there is only a limited space (haha) where free expansion is happening. Therefore, this concept cannot be used to discredit rocket propulsion theory in a vacuum.

What "limited space" are you referring to? The nozzle? The combustion chamber? If energy has to be transferred to an external medium for propulsion to happen, it makes no difference how many "limited spaces" you create inside the rocket. The conclusion does not follow from the premises.

In a vacuum, if one side of a container is opened and gas is being expelled, there will be a pressure difference between the closed side and the opened side.

I am not, however, giving nasa any credibility.

In what way is that different from NASA´s claim that rockets are propelled by recoil (pushing on the roof of the combustion chamber)?

A significant difference in a fluid medium is pressure of the medium. In a vacuum, this is zero. If the pressure is greater than zero, it might aid in the propulsion which could explain the decreasing thrust at higher altitudes. This cannot be extrapolated to zero.

I don´t follow you. If pressure is zero in a vacuum (your words), then what is your argument?

By the way, pressure is so low at a mere 50 km altitude that no type of aircraft (that I am aware of) can remain air-borne. The difference between theoretical zero pressure and the actual near-absolute zero pressure in outer space can be dismissed as utterly insignificant. Molecularly speaking.

[molodyets]

I think you got it wrong.

You made some good points so I rewrote it for better clarity.

I might not have spent the sufficient time to go through all the comments on this thread, but from the hours I did spend, I do not think anyone has properly explained the free expansion idea. This concept has been incorrectly used to claim that rockets cannot work in a vacuum. I will also attempt to explain why rocket thrust would decrease at higher altitudes. I am not, however, trying to defend NASA.

To understand the concept of free expansion, the situation needs to be viewed at the molecular level, at the boundary of the compressed gas and the vacuum. At these boundaries, 1 side faces the other gas molecules and the other side faces the vacuum. When a molecule bounces off another, in the direction of the vacuum, it flies off into space. No energy is transferred outside the gas/vacuum system, and hence no work has been performed on any other matter. This process will continue, until all the gas has been dispersed. The big but in all of this, is that with rocket propulsion, free expansion is not occurring at the combustion chamber surfaces. Therefore, this concept cannot be used to discredit rocket propulsion in a vacuum.

I agree with the official explanation of why a rocket can work in a vacuum. To convince me completely, I would have to see experimental evidence from a credible source, but I do not consider the people at NASA as a credible source. If one side of a container is opened in a vacuum and gas is being expelled, there will be a pressure difference between the closed side and the opened side. The acceleration of the container should then be calculated by the momentum of the escaping gas. This makes sense to me.

If the same situation occurs in a fluid medium (gas/liquid/fluidized bed...) there are so many other factors to take into account. That situation is not as simple. In the atmosphere, the atmospheric pressure is probably the most significant factor. I suspect that the atmospheric pressure adds to the thrust of the combustion chamber which would explain the decreasing thrust at higher altitudes. As explained above, the thrust cannot be extrapolated to zero outside the atmosphere, but again, only experimental evidence would completely convince me. Considering the large mass of the rocket, however, the thrust might not be sufficient to transport it all the way into space...the reason for all the lies.

[hoi.polloi]

I don't disagree with your conundrum, but I think you are right to assume there is no adequate thrust from rocket chambers. Here is why. I think we are meant to understand the "free expansion of gas" concept in, let's say, at least three problems:

1. There is some difference between "inside" the rocket and "outside" but that delineation is not clear to everyone (or anyone?). It is therefore magical reasoning until the point is clearly discussed. Already we have a problem with the functions of the rocket just by trying to understand the so-called design. Where is the one-way diaphragm? How is this osmosis mechanically controlled at different atmospheric pressures from 1 to 1/2 all the way down to 0?

2. In the case of explosive combusting fuel, you have molecules belonging to that process and the unrelated solids of the chamber. The third party is the atmosphere. In atmosphere, the exploding gas can push already impacted gas between atmospheric gasses and the solid chamber. Without atmosphere, the exploding gas cannot be as impacted from the start. You need greater explosions to begin to simulate one atmosphere's worth of pressure on the exploding gas. This robs the exploding gas of a great deal of the formula that works in Earth's atmosphere "for free", as it were. Just how much the fuel explosions must be "stacked" to attempt to create the same effectiveness is largely in question. I agree that solid experiments must be done to determine this; but at least with language like this the average person can begin to conceive of better ways of phrasing it, and designing experiments. This explosion concept is already a problem because of how an ignition behaves differently with or without air about it.

3. The very point of the reaction (the combustion at the moment the chemicals mix/transform/ignite) will not be determined as much by atmosphere (or lack thereof) as much as the time immediately following the beginning of a reaction process will be. That is to say, the fuel is supposed to be mixed at a specific location (presumably, for durability already "outside" the mysterious osmosis process of the chamber — see: the first problem), at which point the reaction is "released" to do its job in whatever environment is "outside". Unfortunately for NASA's theories of "space travel", the greater time this reaction is "in vacuum", the less and less effective the combustion will be, as you can not only fail to push the explosion against the atmosphere (which would give it more power bouncing around inside this vacuum-exposed chamber) but you cannot even get the molecules to keep as close together to remain a potent pushing force against each other. This may sound like the same argument as the second problem but I think there is an important difference, and that is our knowledge of how explosions react within vs. how they react against a vacuum. In vacuum, the entire force of the explosion is supposed to be this fuel propelling from pure chemical reaction alone what was previously aided by all the forces that ordinarily create the "buoyancy" effect of this vehicle lifting through atmosphere.

The argument NASA makes is that the shape of the thrust cone or the shape of the fuel ejector plus the certain balancing of their fuel and/or their other devices is enough to compensate and adjust for all effects from a whole atmosphere to none at all, while maintaining effectiveness in space for days. To me, without their proofs (and I believe the onus is on them to explain why they fake videos of their so-called achievements in the first place) people just accepting this concept, and accepting the videos as authentic without examination, indicates that we have a great deal of faith (perhaps too much) in the power of NASA to solve issues they themselves admit are too complex for them to explain as simply as I have just done. And I trust you'll understand what I mean when I say that is pretty pathetic of them, coming from a 20-some billion dollar annual budget.

[Intothevoid]

Would it not make more sense to use water as a fuel in the upper stages of a rocket in a vacuum as it easily boils when exposed to said vacuum? Perhaps the "cold" of space prevents it's feasibility . On a side note, what stopped the Apollo astroNots from being pushed around by their sublimation cooling apparatus? Where did the vapor and or ice particles from these systems go? I didn't notice any steam or ice coming from their suits.