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What Happens to the Balloon?

07/21/2009 9:47 PM

Dear all

I had a discussion the other day. Just small talk really. A friend of mine had tried to answer this question off the top of his head and soon we were off with speculation regarding anticipated reactions. Here is a diagram for your convenience and an excuse for maybe not phrasing this right.

1. I have a cylinder of a given size and filled with water and made of a material that can with stand high pressures.

2. Inside this cylinder I place a balloon filled with atmospheric air. It is positioned in the center of the cylinder and is equally far away from any side of the container, in mid water. (No strings attached in the diagram)

3. I now introduce a piston sealing the cylinder and exerting pressure on the water.

Q: What happens to the balloon?

1. Does it shrink in size?

2. Does it expand?

3. Does it stay the same?

4. Are the processes inside the balloon of physical and chemical nature at the same time? Would not the heat and pressure, to the nth degree, cause phase changes of the gases inside the balloon and thereby causing chemical reactions?

If 1. is the case then the air in the balloon would heat due to the pressure exerted by the surrounding water.

If 2. is correct I will eat my hat.

If 3. is correct then the amount of heat generated by the pressure, which would expand the gases, will be at equilibrium at one stage.

If 4. is the case were and when to draw the line?

As many of you know I am not any good with complicated formulas and if at all possible, could the consequences of this experiment be explained in simple terms? If need be I'll get some help with understanding the formulas, so feel too discouraged to use them.

I am using atmospheric air which might complicate matters. If using only one gas there would be no possibility of chemical or catalytic reactions at high temperatures/pressures which is what I am really after. How would the gasses combine, if at all, and would they separate after pressure is released? You see, I am one confused man and my neighbor is in the same state of mind.

I hope that this is not seen as homework. It could prove that I had the measles when this was a subject in physics so sorry if this is insulting your intelligence. I mean well, and am trying to put the results into a practical application in the end. Maybe some thing similar has been asked before on CR4 but how to find it?

Hope you can help us out, thanks, Ky.

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#81
In reply to #63
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Re: What Happens to the Balloon?

07/23/2009 5:01 PM

Don't want it to float.

That's the idea.

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#56
In reply to #50
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Re: What Happens to the Balloon?

07/23/2009 4:35 AM

Okay. speaking of spaceships I read about a material 57% harder than diamonds, any one for a bean stock.

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#82
In reply to #56

Re: What Happens to the Balloon?

07/23/2009 5:05 PM

Lonsdeleit is 58% harder than Diamond.

Wurztite is 18% harder than Diamond.

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#79
In reply to #50
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Re: What Happens to the Balloon?

07/23/2009 4:57 PM

Good idea.

At least it should be treated as a sea level atmospheric pressure located in space.

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#30

Re: What Happens to the Balloon?

07/23/2009 12:21 AM

Being compressible fluids both the water and air(inside the ballon) will be compressed when pressure is exerted.Being more compresible the rate of compression of the balloon (I mean, air) will be more and I beleive it will be proportional to it's viscocity.Here,it's assumed that a).the shape of the balloon is a perfect sphere b).it's placed at the center. and c) the the shape of the inner wall of the cylinder is perfect so that the pressure exerted is equal from all sides.

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#83
In reply to #30

Re: What Happens to the Balloon?

07/23/2009 5:07 PM

Water is compressible?

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#36

Re: What Happens to the Balloon?

07/23/2009 1:13 AM

There is a very common devise used in plumbing systems that works exactly like you are describing. It is a pressure tank, or expansion tank, used on pressurized water systems, consisting of a tank and a diaphragm. The diaphragm separates the air from the water being pumped. The air is usually precharged with air to some low pressure below the cut-in pressure set by a pressure switch operating the water pump. When the pump is first turned on, assuming a closed water system, the pressure builds up in the tank, compressing the air. Once the system achieves cut-out pressure, the pump stops. When a valve is open, relieving pressure on the system, the air in the tank expands, driving the water out of the tank until the pressure in the system is below the cut-in pressure of the pump. Then the pump starts running again.

Your ballon would be the equivalent of the air chamber in the pressure tank...

This is generally a low-pressure system- usually 30-60 psi, although tanks are rated much higher. Very common where water is not provided by mains service.

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#42
In reply to #36

Re: What Happens to the Balloon?

07/23/2009 1:41 AM

Nice example cwarner7_11

I understand. The pressures I am thinking of would be hundred fold, at least. The hardware is about a hundredth of what you are presenting but I guess the same principles apply. This has helped to understand that it has been done before but would like some more information with out bogging my self down with not needed hard ware. I am aware that it could get quiet volatile. Another reason to tread carefully.

Just a thought that lingers and wants/needs more attention.

Appreciate your reply, Ky.

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#40

Re: What Happens to the Balloon?

07/23/2009 1:34 AM

In the equation PV=nRT, n (moles of gas) and R (gas constant) remain the same regardless of external influences. Thus, when P, V, or T change, the other two must also change to compensate. Of course, you know this...I'm just prefacing.

You are applying pressure (P). So the temperature (T) will rise in the balloon while the volume (V) decreases. So far I'm sure everyone is with me. So let's say you apply some fixed amount of pressure and hold it there. Archimedes tells me that the balloon will sink until it displaces its own mass of water...but in this case the balloon is moored in place, so it does not move. The surrounding water, a liquid not subject to the Ideal Gas Law, will simply go on being water as though nothing is wrong. It will therefore leech off some of the heat generated by the compression of the balloon. Given time, thermal equilibrium will be reached. However PV still has to equal nRT; if the T (having risen initially) has dropped, and the P has remained constant, then the V must decrease: the balloon gets smaller as the gas therein cools.

Now let's say you suddenly release the pressure. So P goes down, and V goes up while T goes down. (If you could somehow maintain T or V constant, it would be a different story, but you can't.) Once the balloon has returned to near-atmospheric pressure, the T will be lower than it initially was; therefore the V must also be smaller than it originally was. The balloon will not burst. As the T returns to "room temperature" the balloon will slowly expand to its original size.

If the pressure in the system is gradually increased to extreme values, eventually the gas in the balloon will change phase. It will turn to liquid and no longer be subject to the IGL; it will instead behave similarly to the water surrounding it, so when the pressure is so great that the water turns solid, the contents of the balloon will also be solid. Of course, this kind of pressure is only found at the core of very large stars.

There is no reason for the balloon to implode as some have suggested. Submarines implode because the pressure outside the hull is greater than the pressure inside the hull; since the balloon is flexible, it will simply serve as a boundary between two equal pressures.

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#44
In reply to #40

Re: What Happens to the Balloon?

07/23/2009 1:53 AM

Mitsurati

You have fully grasped the situation. I will let this sink in as well. Thank you for putting it in laymen s therm and not throw some formulas about. It also confirms what I had anticipated but I will have to correlate this information in some way. I will get back to you on this, thanks, Ky.

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#53
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Re: What Happens to the Balloon?

07/23/2009 4:24 AM

Good Answer. I'd only add that air weighs about 1.2 Kg per m³ and liquid nitrogen is about 0.8 Kg per litre: round both those numbers to 1 and you can see that the pressure will need to be somewhat less (OK 30 to 40%) than 1000 bar for the gas to start turning to a liquid.

Lets say that it's 700 bar, and, lets assume that the air in the balloon is at 1.4 bar before the compression starts. Then the volume will need to reduce to one 500th of its starting volume so a one foot diameter balloon would be about 1.5" diameter when the gas becomes a liquid. The balloon is about the shape it is when you start trying to blow it up but can't get it started.

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#59
In reply to #53

Re: What Happens to the Balloon?

07/23/2009 8:57 AM

Temp is above the critical point so gas cannot liquefy.

This is a moot point as if it is supercritical it will have strange properties between that of a liquid and a gas.

As an aside, it is theoretically possible to achieve a density in the gas higher than the liquid around it and even higher than any solid or liquid material. Of course the pressures to achieve this are well outside the scope of this discussion.

Mention has been made earlier of sonoluminescence. This can occur with cavitation bubbles but not under steady pressure of a large bubble.

Surface tension effects cause extremely high pressures in the extremely small bubbles formed during cavitation. When these bubbles collapse (they don't actually implode) the energy release is sufficient to briefly cause very high temperatures. The hammer of the "explosion" destroys materials in contact and the temps do likewise.

This is, of course, a very much simplified explanation of a complex phenomenon, but in this scenario, cavitation is not a factor.

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#64
In reply to #59

Re: What Happens to the Balloon?

07/23/2009 11:59 AM

I certainly don't know enough about this, but, surely for the purposes of this discussion the point where the gas becomes the density of the liquid is the point at which it stops acting like a gas (compressible) and starts acting like a liquid (incompressible).

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#109
In reply to #64

Re: What Happens to the Balloon?

07/24/2009 6:54 AM

Provided it is above the critical point, yes.

Howeve, for the purposes of this thread, an assumption has been made of ambient temperature. It is not possible to liquefy air at ambient temperature, because the conditions are above the critical point; it cannot happen.

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#111
In reply to #64

Re: What Happens to the Balloon?

07/24/2009 7:55 AM

No, it is still compressible and the density goes on increasing.

Only if it is below the critical temp will it liquefy.

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#118
In reply to #111

Re: What Happens to the Balloon?

07/24/2009 12:19 PM

Thanks PWSlack and sceptic,

So does this mean that water steam above 374°C is easier to compress than water at room temperature?

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#141
In reply to #118

Re: What Happens to the Balloon?

07/27/2009 5:11 AM

Steam is usually much more compressible than water, being that steam is a gas at moderate pressures. However, temperature is not the whole story, as it is the position relative to the critical point that is of interest, not just the temperature. Its pressure is of interest too.

Above the critical point, there cannot be a phase change for the fluid.

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#120
In reply to #111

Re: What Happens to the Balloon?

07/24/2009 2:15 PM

A supercritical fluid is a fluid at a high enough temperature and pressure that it shows properties as a liquid, but at a high enough temperature that it also shows properties of a gas.

If you have a material that is in the supercritical fluid "phase" and you isothermally increase the pressure, it could become a solid before it becomes a true liquid.

So above the critical temperature, the material can exhibit properties of a liquid if pressure is high enough...does that count as liquefying?

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#124
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Re: What Happens to the Balloon?

07/24/2009 5:48 PM

After concluding what you have just said, I initiated this thread. That is as far as I could think. The paradox (as mentioned) was just too much for me to overcome. It has not been resolved yet, at least not in my head, which would help. Thanks for phrasing this in such a nice way, Ky.

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#74
In reply to #59

Re: What Happens to the Balloon?

07/23/2009 4:10 PM

Good to see you sceptic. This is starting to make more sense by now although I have a lot of reading up to do. Thank for contributing, Ky.

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#85
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Re: What Happens to the Balloon?

07/23/2009 5:13 PM

Sceptic,

Right on.

Jon

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#41

Re: What Happens to the Balloon?

07/23/2009 1:36 AM

Hi Ky,

I'm going to add my two cents worth, at the risk of getting it completely wrong.

Let's assume that the cylinder volume does not change, that the balloon membrane in impermeable to the contained gases, and that the temperature remains fairly constant as the piston moves slowly down.

Firstly, while still in the low pressure range, the balloon will simply decrease in size due to the increasing hydrostatic pressure being equally applied. Yes, the temperature of the air will increase, but it should be absorbed by the water (let us assume that the water to air ratio is very high).

As the pressure is increased even further, one starts to reach a point where the component gases of the air would condense to form a liquid - the phase change that you mention. The component gases will condense at different pressures, typical of their characteristics and pressure/temperature graphs (it is too early in the morning where I am to bother to look up which gas will condense first, but in any case I don't think that is too important right now).

At some point the first gas will condense, the others remaining liquid. As the pressure is increased even further, the second and other gases will condense. I don't think the temperature will suddenly drop as this condensation occurs - one simply has to look at the pressure/temperature graphs to se this - you can google it). At some point all the gases will have condensed. If one now slowly releases the pressure the reverse would happen. If one relased the pressure rapidly, then temperature differences would play a significant role and the water could freeze as the gases absorb heat from the water.

I don't think there would be any chemical reactions between the various gases as we have assumed that the temperature remains constant. I leave it up to more learned members to discuss the results of removing this assumption.

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#46
In reply to #41

Re: What Happens to the Balloon?

07/23/2009 2:11 AM

Thank you Garyvan

Good to have you @ CR4

The reactions and answers are getting more refined at this stage of the thread and I appreciate your input. To me, although not learned, this seems all in the common sense department. The information I am receiving has to be translated to a system which is in its infancy and only a small but not negligible part of it.

It is of great help that you have refined the question but I could not and would not start a post with all those complexities involved. Del (the cat) would not touch them with a bargepole for example, although he would know a few things about it.

Your reply has been of great help and I shall ponder, Ky.

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#70

Re: What Happens to the Balloon?

07/23/2009 2:15 PM

I'm just blasting through here, so forgive me if I am saying what has already been said.

This is the principal on which a Cartesian Diver works. These are quick and fun to make, and you can use almost anything to weight the "diver" to only slightly positive buoyancy. The diver can be as simple as a small balloon, barely inflated, a twisted-shut plastic bag, etc. Squeeze the bottle, and the diver sinks, release and it rises.

Have fun.

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#72
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Re: What Happens to the Balloon?

07/23/2009 2:26 PM

Lord Vader beat you to it.

http://cr4.globalspec.com/thread/40799?frmtrk=cr4sd#comment425080

Be careful. He might find your lack of diligence...disturbing. (ksshh-kshhhhh, ksshh-kshhhhh)

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#80
In reply to #72

Re: What Happens to the Balloon?

07/23/2009 5:00 PM

Blinky, lack of diligence? Scary thought. Like with balloons he can rise to the occasion or just use the pressure release to get out of here. You are right, he is not an individual who would swirl away making a high pitched farting sound even if he would be letting pressure off, Ky.

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#78
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Re: What Happens to the Balloon?

07/23/2009 4:52 PM

Why blast, I thought that you could be of some help here. While posting I thought that you would get into this discussion. The Cartesian Diver is only the tip of the ice berg but you would possibly have recognized that by now. There is a nice experiment displayed in the above mentioned link but again it touches my situation only peripheral.

Thanks Blink, Ky.

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#71

Re: What Happens to the Balloon?

07/23/2009 2:25 PM

The balloon will rise to the occasion...

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#76
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Re: What Happens to the Balloon?

07/23/2009 4:25 PM

That is the true agenda, I just have to find out how many at one time will rise to the occasion so all does not end up in a big splatter of balloons and body tissue. Humor is if you lough anyway, Ky.

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#105
In reply to #76

Re: What Happens to the Balloon?

07/24/2009 2:52 AM

But of course the balloon is double walled and the disparity of temps may be compensated by pressure adjustment within the outer wall

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#106
In reply to #105

Re: What Happens to the Balloon?

07/24/2009 3:23 AM

Hi bwire

Are you sure you responded to the right post? It's happened to me in the past.

Am I missing something?

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#93

Re: What Happens to the Balloon?

07/23/2009 7:52 PM

Problem I see here generally is that KY, intentionally or not, set this up as an ideal problem, what happens to the contents of the balloon at nth pressure.

Therefore instead of all the conditioning of this or that factor following it through as an ideal, the end result is nth pressure, nth compression, and BANG!; the rerun.

Just as I set out above before reading all the way down.

If we are scientists, or rely on scientific method and results, then I think we are obliged to carry a mental experiment through all the way to its final outcome.

Then you can go back and play with it and jigger one or another condition.

Sorry. Give me an ideal situation and I become a purist.

Surely though, somebody must have run a series of tests to see what the results are, on gases at least, of subjecting them to the most extreme pressures of which we are capable.

If Ky has a practical end in sight he ought to look up such a possible experimental series.

j.

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#101
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Re: What Happens to the Balloon?

07/24/2009 1:06 AM

Hi Jack

I was overseas today so I lost a bit of time out of my day and can only correspond now. Methodically, as I am, I will go one post at the time.

If Ky has a practical end in sight he ought to look up such a possible experimental series.

Very down to earth, I must say. I do not think that the experiment I am preparing/planing has ever been done before, at all. As with the balloon that could be a bubble the liquid does not necessarily have to be H2O. I have given this "liquid" a name but it would only confuse matters and make me look irresponsible or just plain crazy if I mentioned it here.

Then you can go back and play with it and jigger one or another condition.

Exactly, my point, Ky.

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#98

Re: What Happens to the Balloon?

07/23/2009 9:08 PM

As a variation on the same theme, what happen to the air bubbles without the skin of a balloon if this was in the cylinder under pressure? What would happen to all the little "balloons" ?

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#99
In reply to #98

Re: What Happens to the Balloon?

07/23/2009 11:44 PM

They would get smaller, but not change their shape, much. Then, under enough pressure they will become round, as the hydrostatic pressure pushes with more force on the smaller portions of the bubbles.

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#104
In reply to #98

Re: What Happens to the Balloon?

07/24/2009 1:28 AM

Very close but just not close enough, that's all I'd say.

I have a rock at home filled with water. They call them something, can't remember now. There would be crystals inside if I cracked it. Supposedly it has been in there for some 280mil years. The guy that sells them says he had the water tested and it was under no pressure when opened. The water was just that, H2O. Just another useless piece of information really, or is it? Ky.

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#117
In reply to #104

Re: What Happens to the Balloon?

07/24/2009 11:09 AM

Could be a geode.

Crystals typically quartz.

Most of the ones I open are dry. The rock is slightly porous.

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#123
In reply to #117

Re: What Happens to the Balloon?

07/24/2009 5:38 PM

A geode, thanks for that. So you have found some with water in them? Its fascinating to have a time capsule like this, Ky.

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#110

Re: What Happens to the Balloon?

07/24/2009 7:01 AM

Isn't this a bit like a sponge that is not fully saturated with water? What happens when this sponge is squeezed?

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#146
In reply to #110

Re: What Happens to the Balloon?

07/27/2009 11:43 PM

PWSlack,

PETA will come after you because a sponge is a living creature.

Unless you mean a fake one like a blow-up sponge doll.

Jon

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#147
In reply to #146

Re: What Happens to the Balloon?

07/28/2009 4:10 AM
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#148
In reply to #147

Re: What Happens to the Balloon?

07/28/2009 4:38 AM

OK Randall, back to the drawing board. Here is a painted impression of what could be going on. There could be crystals in a sponge and be they made of ice.

Others loose their marbles, I find them, Ky.

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#150
In reply to #147

Re: What Happens to the Balloon?

07/28/2009 5:34 PM

Yes!!!

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#113

Re: What Happens to the Balloon?

07/24/2009 10:12 AM

Ky

First of all, the ballon will not get positioned as per your diagram, it will float in open cylinder and stay in contact with bottom of the piston.

When you increase piston load, the pressure inside the cylinder will increase, exerting furthur pressure on the balloon surface. Depending on strength of the ballon material as pressure increases, the balloon will get burst and the air will get locked preventing further movement of piston.

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#114
In reply to #113

Re: What Happens to the Balloon?

07/24/2009 10:18 AM

Why doesn't the air compress, then?

What causes the balloon to burst?

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#115
In reply to #114

Re: What Happens to the Balloon?

07/24/2009 10:48 AM

PWSlack,

Possible ballastic strain, beyond the elastic stretchability of the balloon layer .

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#116
In reply to #115

Re: What Happens to the Balloon?

07/24/2009 10:57 AM

The only thing that would cause the balloon to burst is a pressure differential across the balloon wall. That differential is greatest before the experiment starts, when the balloon is first inflated. As pressure is increased by the piston, the pressure differential (i.e. stress on the balloon) will actually decrease. As the pressure outside the balloon (hydrostatic pressure) increases, the pressure inside the balloon will increase by an equal amount.

The balloon will only burst if you decrease the pressure outside of it.

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#157
In reply to #116

Re: What Happens to the Balloon?

07/30/2009 4:58 AM

Mitsurati,

Thank you for the correction information and posting your valuable comment. I was rather imagining about the open air crushing of balloons, whereas this situation is a compressive stress, something connected to thermodynamics. I could get a lot of new insights. Wish Ky all the best in his endeavour.

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#158
In reply to #157

Re: What Happens to the Balloon?

07/30/2009 5:03 AM

Thank you Sir, Ky.

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#121
In reply to #113

Re: What Happens to the Balloon?

07/24/2009 2:32 PM

" Inside this cylinder I place a balloon filled with atmospheric air. It is positioned in the center of the cylinder and is equally far away from any side of the container, in mid water. (No strings attached in the diagram)"

I'd suggest you think about this some more.

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#126
In reply to #113

Re: What Happens to the Balloon?

07/24/2009 6:06 PM

s.udhayamarthandan

If we were all in a meeting and you, at this stage of the discussion, would have said that, I would have asked you to leave and blow up a few balloons to keep the kids entertained while we lock horns. Read the opening post, that is the least you could do to have a say in this simple matter. Read the other comments too, it would help you understand the problem at hand.

I wonder some times...., Ky.

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#140

Re: What Happens to the Balloon?

07/25/2009 4:24 AM
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#149

Re: What Happens to the Balloon?

07/28/2009 3:55 PM

Hi Ky,

I'm not sure what this is all about, but it sounds a bit like a hydraulic accumulator, (which I worked with for a couple of years)

the accumulator is a device for storing hydraulic fluid at pressure. (and therefore energy)

The systems we worked with had an operating pressure of 3000psi. We routinely tested them to 4500 psi, and the shells themselves were factory tested to 6000psi. (they come with a cert)

you can get them in different volumes, from quarts to gallons.(imperial)

They use various bladders internally (bubbles?) One side of the bladder is precharged with nitrogen. (@1000psi) The other side has hydraulic fluid pumped against it at 3kpsi. The nitrogen compresses to 1/3 of the space, as the pressure ratio is 3:1 (3000:1000) and essentially stores 2/3 of the nominal bottle volume of fluid. (ie: a 15 gallon accumulator bottle stores 10 gallons of fluid at pressure) The Nitrogen acts like a spring, and compresses and decompresses with changes in fluid pressure. (We also used them as pulsation dampeners to smooth out the pressure signal after the pump.)

you can discover a wealth of information here, and elsewhere.

we used these devices in control systems for hydraulic blowout preventers (BOP's) for oil drilling. These BOP's were typically rated to close off wellbores which could be rated up to 10,000 psi. (for our sector)

good luck, and pay close attention to your relief valve orientation Hydrualic pressure isn't generally as dangerous as large amounts of compressed air, as the pressure drops immediately upon a leak or rupture. but it is still dangerous.

Chris

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#151
In reply to #149

Re: What Happens to the Balloon?

07/28/2009 6:03 PM

Good to see you Chris

That is very good information and it +/- comes to the point of the matter. It confirms that what I am trying to achieve has been done before, just in another application but in some way using the same principles. GA and great link.

I Have to sort out a few things and need a slap on the wrist regarding safety precautions. While setting up the experiment I spend as much as 1/3 of the time on safety precautions and have my doubts if that is enough. With my new setup it should be more safe to operate and get even higher pressures than you have mentioned on a much smaller scale. Have not got the "real bullet" yet but when, I shall be super careful once it is in place, which could take a while.

I'm not sure what this is all about, but it sounds a bit like a hydraulic accumulator.

I wonder what would happen if you knew all about it . Talk to you soon, Ky.

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#152
In reply to #151

Re: What Happens to the Balloon?

07/28/2009 6:31 PM

lol.. at this point I'm more interested in the beach on the tropical island in the south pacifice than the technology.... but... the time is not yet right... vacation next year would maybe work out if I can hold down a job that long eh?

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#153
In reply to #152

Re: What Happens to the Balloon?

07/28/2009 7:31 PM

Just to rub it in here is what you are missing. Never mind the brewing storm, she'll be right as rain Mate.

Maybe I should just hire you and your talents but that is as in the stars as the technology we (you know who) are working on. Just hold down that job, cavalry is on the horizon, Ky.

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#162
In reply to #152

Re: What Happens to the Balloon?

01/23/2010 7:36 PM

lol.. at this point I'm more interested in the beach on the tropical island in the south pacifice than the technology.... but... the time is not yet right... vacation next year would maybe work out if I can hold down a job that long eh?

Hi Chris

I was just today recapitulating what has happened since this thread was started. Heaps I must say. Just this thread should give you a few clues of what I am on about. Thanks to all involved and who still receive this. Talk to you soon, Ky.

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#163
In reply to #162

Re: What Happens to the Balloon?

01/23/2010 9:24 PM

Ky,

It was a good thread. I enjoyed it partly because of the goofy answers and mostly because it opened up a sleeping area of my mind.

Jon / kuduk

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#154

Re: What Happens to the Balloon?

07/29/2009 8:17 AM

size become small. easy.

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#155
In reply to #154

Re: What Happens to the Balloon?

07/29/2009 4:32 PM

No, I will not give up!

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#156
In reply to #154

Re: What Happens to the Balloon?

07/29/2009 4:51 PM

How do you get the brain of an inventor to pea size?

Blow it up, easy.

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#159

Re: What Happens to the Balloon?

09/12/2009 10:10 PM

Hello Ty,

Welcome to the Australia group, I had a similar enquiry about a helium filled ballon on the moon; we all know what happens to the ballon on Earth but what would happen to the same ballon released on the moon?

Looking forward to future contact,

Transparency.

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#160
In reply to #159

Re: What Happens to the Balloon?

09/13/2009 12:29 AM

Hi Guest

First: you are getting me mixed up with Ty Williams the Cowboys football player.

Second: my real name is Ky.

Third: this is beyond having fun with thought experiments by now. I am thinking of applying the results of this 'thought experiment' on this planet and in real time and not on the moon.

Fourth: Transparency, is that your name or is that wishful thinking?

With all due respect, Ky.

PS: why not sign up to CR4 and I can find out a bit more about who you are.

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#161
In reply to #159

Re: What Happens to the Balloon?

09/13/2009 8:32 PM

Balloon on the moon drops to the lunar surface... Assuming the vacuum doesn't cause it to burst.

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#164

Re: What Happens to the Balloon?

01/25/2010 4:26 AM

If you go scuba diving you are in effect pressuring 2 balloons, namely your lungs. They definitely collapse or else you would not need a regulator on your tank to keep increasing the pressure as you go deeper. My understanding is that liquid (water) is not compressible but it does increase in pressure as you stack more and more water on it. Cool question though.

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#166

Re: What Happens to the Balloon?

05/17/2010 2:33 PM

The pressure of the water is transmitted to the gas in the balloon. As the water pressure increases (piston moves down) the volume of gas in the balloon reduces and, since work is being done, the temperature of the gas, or of the gas and water by heat conduction, also increases. The situation is similar to the "hydraulic accumulator".

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#167

Re: What Happens to the Balloon?

05/17/2010 2:51 PM

The piston exerts pressure on the water, which is transmitted to the gas in the balloon. While water is nearly incompressible, the gas in the balloon will reduce in volume as the pressure increases. Since work is being done, the gas will also increase in temperature and in time, by conduction, the water will too. The device is similar to the common "hydraulic accumulator", wherein pressurized hydraulic fluid is stored by compressing gas.

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#168
In reply to #167

Re: What Happens to the Balloon?

05/17/2010 3:02 PM

"What happens to a balloon" when it is exposed to the extreme pressure and potentially extreme heat caused by rapid compression of the air in it? Besides the obvious, does it blend with the water, melt, burn, explode forcing the piston to be ejected into space?

Kuduk

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#169
In reply to #167

Re: What Happens to the Balloon?

05/17/2010 5:19 PM

Thanks esbuck

Chrisg288 had submitted a very similar answer in the early stages. It was very helpful although for my application a few things had to be changed. It is, after all this time, nearly up and running. Your comments are confirming that it was worth while to inquire here and not suck the internet and waste a lot of time.

See what happens, Ky.

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#170
In reply to #169

Re: What Happens to the Balloon?

05/17/2010 5:39 PM

Ky,

Yep, and it liked the 6 rated answer because of the final comment:

"Actually the balloon is irrelevant the same thing would happen if you just had air alone in the cylinder and pressurized it with the piston."

The oil leak in the Gulf of Mexico could use an application like that.

Kuduk

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#171
In reply to #170

Re: What Happens to the Balloon?

05/17/2010 6:01 PM

You know, that is exactly what I was thinking of. No, you can't even imagine what I am thinking of because it would include a mechanical device which I can't show here. Maybe later, when the "bore that I have drilled" lets some $$ flow my way.

Worse than being told to shut up is when one shuts up. Not my loss but it still hurts. It seems to be coming full circle though. I can already calculate from the radius, that it is a larger than 'normal' circle.

Nope, speaking in riddles will not help any one, but me, Ky.

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#172
In reply to #171

Re: What Happens to the Balloon?

05/17/2010 7:18 PM

Ky,

Keep on keepin' on.

Don't let them demagnetize your island.

Kuduk

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#173
In reply to #172

Re: What Happens to the Balloon?

05/17/2010 7:28 PM

They have tried, you know.

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#174
In reply to #173

Re: What Happens to the Balloon?

05/17/2010 7:30 PM

Dang!!

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