Does Rocketry Work beyond Earth's atmosphere?

[hoi.polloi]

A funny idea for an experiment! But flawed and naive in terms of proving NASA's rocketry beyond Earth's atmosphere.

As we have already gone over countless times in this thread, liquid is not gas and a tiny vacuum chamber is not the exponential void above Earth's atmosphere.

Furthermore, a lightweight tin can ejecting its entire liquid contents at once is not the same as what NASA's fuel injected gas explosions are said to be doing.

Finally, it is also wrong to say that the single frame reviewed by the experimenter shows any behavior of invisible gas.

I won't move this to the Derailing Room because it demonstrates how hard it is for the average person to wrap their minds around the concepts already over-explained.

[Flabbergasted]

Furthermore, a lightweight tin can ejecting its entire liquid contents at once is not the same as what NASA's fuel injected gas explosions are said to be doing.

Exactly.

What we see in the first frame of the experiment is simply the recoil effect of an "explosion" of liquid through one extremity of the can. Akin to a gunshot, not like a steadily propelled 'gas rocket'.

Cute experiment, by the way.

[Flabbergasted]

In this excerpt from the 1989 "documentary" For All Mankind (http://www.imdb.com/title/tt0097372/?ref_=nv_sr_2), we get a good view of how the Saturn V rocket was propelled into infinity and beyond, viewed in profile (at 0:38) from a very special vantage point.

https://www.dropbox.com/s/pm2x0nvh9emij ... o.avi?dl=0

[pov603]

and the "g-force" experienced by those "super-strong" astro-nots wasn't a problem for them, letting them use high-tech ring-folders without resistance...

[kickstones]

A funny idea for an experiment! But flawed and naive in terms of proving NASA's rocketry beyond Earth's atmosphere.

As we have already gone over countless times in this thread, liquid is not gas and a tiny vacuum chamber is not the exponential void above Earth's atmosphere.

Furthermore, a lightweight tin can ejecting its entire liquid contents at once is not the same as what NASA's fuel injected gas explosions are said to be doing.

I won't move this to the Derailing Room because it demonstrates how hard it is for the average person to wrap their minds around the concepts already over-explained.

Hoi, I would class myself as a fairly average person and at the risk of appearing foolish, can you explain what would happen if you released water in the vacuum of space?

Because in a tiny vacuum chamber it turns to ice.


full link: http://www.youtube.com/watch?v=UG7nsZkVZc0

If the same reaction in the above experiment occurred by a rocket releasing water on entering the emptiness of space would that not give a solid base for outpouring molecules, released by let's say a kind of steam explosion, to meet resistance resulting in thrust thereby maintaining momentum?

[kickstones]

I just found the report linked below which may give an insight to what might happen to water released in space...

The release of the water caused the development of a "cloud" which expanded turbulently with an Initial average expansion rate velocity of 1,05 km/sec. however, expansion rate velocities as high as 3.60 km/sec were observed. Extensive cooling was also encountered with the water release. The estimated temperature of the cloud was -110 C.

An Analysis of the Second Project High Water Data
https://ntrs.nasa.gov/archive/nasa/casi ... 078055.pdf

[patrix]

If the same reaction in the above experiment occurred by a rocket releasing water on entering the emptiness of space would that not give a solid base for outpouring molecules, released by let's say a kind of steam explosion, to meet resistance resulting in thrust thereby maintaining momentum?

Hi kickstones,
I don't think so since space (to the best of our knowledge) is an unrestricted vacuum. This in turn means that no pressure buildup can occur since all gas molecules released in that frictionless vacuum will merrily float away at the same speed without being able to interact with each other. So the example is not transferable to a rocket in vacuum.

[hoi.polloi]

Hoi, I would class myself as a fairly average person and at the risk of appearing foolish, can you explain what would happen if you released water in the vacuum of space?

Don't worry, kickstones. I'm the fool, here. I have no idea what would happen in the vacuum of space since I don't think we've been there. We may theorize, though (or fantasize, like in so-called "science fiction").

[kickstones]

If the same reaction in the above experiment occurred by a rocket releasing water on entering the emptiness of space would that not give a solid base for outpouring molecules, released by let's say a kind of steam explosion, to meet resistance resulting in thrust thereby maintaining momentum?

Hi kickstones,
I don't think so since space (to the best of our knowledge) is an unrestricted vacuum. This in turn means that no pressure buildup can occur since all gas molecules released in that frictionless vacuum will merrily float away at the same speed without being able to interact with each other. So the example is not transferable to a rocket in vacuum.

Hello Patrix, I understand the logic of no pressure and gases, what I'm trying to fathom out is what would happen to a sufficient body of water (liquid) emitted out of the rocket in space?

If a means such as a steam explosion (see below), would the foremost water molecules emitted turn to ice, and if the latter molecules met the ice mass would enough thrust force be created to maintain momentum of the rocket?

From Wikipedia.....

Steam explosion

A steam explosion sprays steam and boiling-hot water and the hot medium that heated it in all directions (if not otherwise confined, e.g. by the walls of a container).

If a steam explosion occurs in a confined tank of water due to rapid heating of the water, the pressure wave and rapidly expanding steam can cause severe water hammer. This was the mechanism that, in Idaho, USA, in 1961, caused the SL-1 nuclear reactor vessel to jump over 9 feet (2.7 m) in the air when it was destroyed by a criticality accident.

Many large-scale events, including foundry accidents, show evidence of an energy-release front propagating through the material, where the forces create fragments and mix the hot phase into the cold volatile one; and the rapid heat transfer at the front sustains the propagation.

https://en.wikipedia.org/wiki/Steam_explosion

[kickstones]

Patrix, working on the assumption that a water carrying rocket managed to get into space, what influences would vary in that medium to the ground level vacuum water / ice experiment?

For example, two phenomena documented to occur in space are solar radiation pressure and solar wind pressure, would they have any significant influences in water transformation and rocket mobility?

[patrix]

Patrix, working on the assumption that a water carrying rocket managed to get into space, what influences would vary in that medium to the ground level vacuum water / ice experiment?
For example, two phenomena documented to occur in space are solar radiation pressure and solar wind pressure, would they have any significant influences in water transformation and rocket mobility?

Dear kickstones,

I'm flattered you ask me, but I can only speculate as much as anyone. Supposing space is as described, I have no idea if that is the case since most likely nothing man made has went above the atmosphere, and if something have, the last thing the people responsible would probably do is to give us any factual information of the nature of space. Anyway, if space is a vacuum, a water mass would “cold boil” (dissipate to a gas in low temperature), this in turn will make it colder as it’s losing heat in that process. And if space is very cold in itself I’m not sure if the water will freeze instantly or if it will be able to dissipate first and become small ice droplets. If water was ejected with pressure behind it, there might be some Newtonian inertia enabling the object ejecting the water to move in the opposite direction. But I find the “Newtonian explanation” of rockets laughable since inertia alone cannot produce any significant movement. To achieve that, there has to be an energy release that can react with the surrounding environment. Say, for example, you have a ship and instead of using the diesel to fuel the engines you start throwing or catapulting the diesel barrels from the back of the ship. That would hardly produce any motion.

[The_White_Lodge]

Patrix,

You have oversimplified this "barrel thrown off of ships" thought experiment. If you are wondering why a bunch of people chucking barrels off a ship would produce very little motion in the opposite direction despite Newton's laws of motion being correct it is because most of the force generated by the throwers of the barrels when transferred to the ship would be along the vector perpendicular to the horizontal motion of the barrels flying off the ship. This is because the throwers of the barrels are connected to the ship via their feet which primarily push through the vertical plane. So, the ship would experience an increasing bounce, but not much directional motion, and indeed were you to carry this experiment out you would notice much greater bobbing of this respective ship immediately during and after these barrels were being thrown.

[patrix]

Dear WL,
Yes, I may not be very good at giving thought experiments around this. Earlier ones in this thread have been better. But the point is that Newtonian laws are perfectly fine, it's just that they cannot do much in terms of propulsion. Another example would be if the ship was a destroyer and you directed and fired all cannons aft. High energy, high velocity, but not much propulsion.

[The_White_Lodge]

Patrix,

If you don't believe in the laws of classical mechanics, I don't have a problem with that, but if you do believe in them then I do have a problem with you claiming they don't cover all forms of motion.

The ship destroyer example you cited has the same flaw in logic as your barrel example, except a ship firing a cannon will generate considerable directional motion in the opposite direction of the cannonball, the amount of this motion would depend on several factors the weight of the ship being one of them.

However, let us turn to a much simpler example of propulsion, the fire cracker. Are you suggesting that firecrackers are not driven upwards by propulsion?

[Flabbergasted]

Are you suggesting that firecrackers are not driven upwards by propulsion?

TWL and patrix, if you read the entire thread you will see those scenarios have been covered ad nauseam. Each force (wheels, water, air) pushes most efficiently against an external medium of the same nature. No need to go there again, unless you have found something that pushes against the void.