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Erazman
Feb29-04, 07:04 PM
Theres already methods of harnessing energy from gravity (like from the flow of water), but not in very massive amounts. What if we drilled a very deep hole into the ocean (down to the extremely hot farthest reaches of the crust where water will evaporate easily) and set up a generator at the bottom? Have a massive pipe connected from the ocean water to the bottom of the pit. The hole wont fill up with water if ventilate the steam to the air above the ocean (driven by the difference in pressure). Mineral Insulated cables could be run down to the generator. I'm talking extremely hot conditions here to allow the massive amount of water flow to evaporate ASAP.. we would actually be using the earth's heat as a driving force to return the water...

Law of Convservation remains unbroken.. because the steam that rises back up the hole has lost its potential energy from the deep pressures of the ocean and the gravity of the hole... and has given it to us.

There's already a thread on here that talks about harnessing energy from the bottom of the ocean, but not from BENEATH the bottom of the ocean. [!:)]



[6)] [6)]

russ_watters
Mar1-04, 01:07 AM
Sounds pretty good to me. The main problem is drilling the hole and setting up a generator miles under the ocean floor.

Erazman
Mar1-04, 03:19 PM
Originally posted by russ_watters
Sounds pretty good to me. The main problem is drilling the hole and setting up a generator miles under the ocean floor.

okay, now putting aside the problems that come with it (such as disturbing ocean life, the costs of deep ocean floor drilling, etc), can we figure out, theoretically, how much KW/hr we could produce?

Variables:

crust beneath the ocean: 6.5 miles
(lets set it up short of 6 miles) = 30,000 FEET
That should give us plenty of heat to evaporate the water reservoir fast enough so our operation doesnt flood.

Ocean depth of 15,000 feet
(a TREMENDOUS amount of downward pressure)

10 ft diameter pipe (wide open) blasting a large turbine.

Assuming the generator/pipes can withstand this force, and wont overheat.. how much power could we harness?

NateTG
Mar1-04, 04:16 PM
Ultimately, the peak power you can get depends on the flow rate you have.

Since this is a heat engine, you can approximate the peak efficiency at 1-\frac{T_{min}}{T_{max}}
Let's say that the temperature of the lava is 10000 degress Kelvin, and the temperature of the water is about 300 degress kelvin, so the peak efficiency is quite high.

Now, assuming that water has a specific heat of four joules per degree per gram, we can figure that you'll get about 39000 joules of work per gram of water at peak efficiency. That translates to a peak power of roughly 40 gigawatts per ton of water per second.

Since water has a specific density of 1 ton per cubic meter, that's a lot of energy even with a relatively small pipe.

Of course, thermodynamic efficiency is not likely to break 10%, so you're looking at a much smaller amount of power.

On the other hand, the technical challenges associated with actually creating and maintaining that kind of pipeline are very hard.

Geothermal power systems on the Megawatt scale are in use at several locations. You can google for more information.

Effectively, the peak power is equal to the peak heat transportation.

Sariaht
Apr4-04, 03:40 PM
Emmmm. Hmmm!

Let's say we drilled a whole under the north and south pole, and revealed the earth's core; a water stream toroid would form around the hole, since the high speach of gravity drags the water to the pole, and the hot water bursts out of the hole like a geiser. If you managed to tame the energy, you would perhaps gain a bit from doing this! besides, the poles magnetic fields would also become stronger, and its differing position could perhaps be used as an energysource etcetera.

jammieg
Apr10-04, 03:06 PM
There might be an easier way, if the aether theorists are right and gravity propogates through the aether medium like sound through air then an aether vacuum might work better, gravity could supposedly be switched on and off like a light switch, but experimenting with it I haven't tried, somehow magnetism would be needed to pump out the negative and positive aether in a chamber that was designed to make a barrier to both positive and negative aether. If you strongly doubt Tesla's aether theories take a look at tesla lines and ask yourself what a superimposed + and - foam would act like near a magnet?

Nice coder
Apr11-04, 08:32 AM
You do know that aether doesn't exist?

Sariaht
Apr11-04, 02:01 PM
If there were magnetic ether particles you could make a pretty advanced telescope.
I'm sure you could create ether fusion, though the fact that you cannot use ether as a battery, since the particles to small might and perhaps already have lead to other conclusions.

chroot
Apr12-04, 05:39 AM
Sariaht and jammieg,

Please keep your posts about non-mainstream science out of the general forums. They are welcome only in the Theory Development forum.

- Warren

username
Apr20-04, 08:51 PM
I gues s this is the same sort of thing as geothermal power plants except being at the bottom of a ocean is closeer to the earths core thus more heat, I hav always thought this kind of energy transfer could be profitable compared to say deep drilled oil wells in the ocean, dont really know much about it, btw: for the post about aether look up michleson - morley experiments in google, mind u that was a long time ago.

sheldon
Apr22-04, 05:45 AM
As the steam rose up your pipe vent it would cool and recondense and fall back into the pipe filling it up with water, clogging the system. The water entering the system would cool the lava rock and would stop the system unless you were continually drilling or scraping off the crust.

kronchev
Apr22-04, 10:57 AM
okay, now putting aside the problems that come with it (such as disturbing ocean life, the costs of deep ocean floor drilling, etc), can we figure out, theoretically, how much KW/hr we could produce?

Variables:

crust beneath the ocean: 6.5 miles
(lets set it up short of 6 miles) = 30,000 FEET
That should give us plenty of heat to evaporate the water reservoir fast enough so our operation doesnt flood.

Ocean depth of 15,000 feet
(a TREMENDOUS amount of downward pressure)

10 ft diameter pipe (wide open) blasting a large turbine.

Assuming the generator/pipes can withstand this force, and wont overheat.. how much power could we harness?


youre going to want something A LOT bigger than 10 foot. As in a 50 foot diameter pump.

kronchev
Apr22-04, 10:59 AM
As the steam rose up your pipe vent it would cool and recondense and fall back into the pipe filling it up with water, clogging the system. The water entering the system would cool the lava rock and would stop the system unless you were continually drilling or scraping off the crust.

Itll only cool if it hits something cooler. I suspect the steam would be going very, very fast under all the pressure so in an insulated system (esp surrounded by much much hotter rock) it not only wont have time to cool off, it wont have anywhere to cool off to

the advantage to that is you wont drain the ocean, as soon as it blasts to the surface, itll condense very quickly :p

Atrius
Apr22-04, 10:59 AM
why not simply make a machine above the surface, weighted with magenets so it rotates?

russ_watters
Apr22-04, 03:32 PM
why not simply make a machine above the surface, weighted with magenets so it rotates? Weighted with magnets? What would that do? Could you elaborate?

MythioS
Apr25-04, 11:37 AM
i think hes thinking a wheel basically.. with like tank track treds all around it. each side of the treds would have an opposing charge. basically the same idea as that little solar glass thingy with the white n black sided diamonds. except instead of dark n light it would be + & -. and instead of solar energy it would be magnetism.

Simon666
May20-04, 06:50 AM
One problem is just as with existing geothermal plants, your hot water cools the underneath hot rock or lava so after a while power output decreases and you would need it to regenerate a couple of years. Drilling holes in the ocean floor is also not exactly the cheapest and easiest thing.

runemerlin
Jul17-04, 03:19 AM
There is no problem. All of the various steam driven power plants in use today utilize a closed system. As the steam leaves the turbine it goes through cooling coils surrounded by water pumped from a nearby river or lake. Once it is cooled it is pumped back into the boiler tubes. This is possible, and doesn't use up all of the energy gained, because, though the pressure is just as high at this end as at the turbine end, the volume to be introduced is much lower than the volume escaping. (This is the reason a jet engine even works.) The steam generated at the bottom of the system can be cooled VERY effieciently by the water at the ocean floor (which is actualy closer to 275 degrees k), and allowed to simply fall back down to the boiler. For best efficiency, however, the generator needs so be as close to the heat source as possible, for obvious reasons.

Kenneth Mann
Jul17-04, 02:03 PM
Am I missing something here? Assuming that the prodigious engineering feat of drilling, temperature and pressure control,etc. can be handled; let's ignore the action of the water above, and consider that of the magma when it suddenly finds a hole above it. It sounds like instant volcano to me. Why not consider something infinitely simpler (but still not easy), like pressure capping Kilauea (while somehow still allowing the lava to escape) and pumping water up into it's bowl. This will be an incredibly difficult and expensive project, but still a lot easier and cheaper than the sea floor exercise.

shonagon53
Jul17-04, 11:03 PM
May I remind the readers of this post, that in France and Germany, artificial thermal energy pits are already being tested? They're just very deep holes through which water is pumped, which gets heated and then travels back up. One in France (500 metres deep) created half a megawatt continuously. In Germany they're building several of around 2000 metres deep.

So this idea is a bit baked.

You don't need to go offshore for this. Just drill a hole onshore, and divert water into it. That's all you need.

russ_watters
Jul19-04, 02:25 PM
You don't need to go offshore for this. Just drill a hole onshore, and divert water into it. That's all you need. Well, that and a geothermal source.

Kenneth Mann
Jul19-04, 04:03 PM
Well, that and a geothermal source.

We have one. It's called the Yellowstone Caldera, and I wouldn't touch it! It's potentially the largest supervolcano in the world, and it's probably due to erupt on its own. If so, we're all toast. Maybe this is an opportunity we should just sit out.

Marijn
Aug4-04, 05:12 AM
Drilling holes like the 30k feet desribed earlier is impossible.
And will remain to be for quite a long time.
If only because you can't spin a pipe 30k foot long, it wouldn't hold out.
Appart from the fact that ould you get close you'll start warming up you bit it would get to weak to keep chewing ground.

This completely besides tha fact that its damn near impossible to drill at 15k feet depth.

Just keep it onland, then it'll work.
Drilling that deep ill never work.
But cool idea.

Takereasy
Aug6-04, 05:00 PM
Am I missing something here? Assuming that the prodigious engineering feat of drilling, temperature and pressure control,etc. can be handled; let's ignore the action of the water above, and consider that of the magma when it suddenly finds a hole above it. It sounds like instant volcano to me. Why not consider something infinitely simpler (but still not easy), like pressure capping Kilauea (while somehow still allowing the lava to escape) and pumping water up into it's bowl. This will be an incredibly difficult and expensive project, but still a lot easier and cheaper than the sea floor exercise.

What you could probably do is pump tons and tons of water into the bowl of a volcano, and just let it boil off. A localized weather pattern should be created by the evaporation/condensation cycle. Once that weather pattern is established, you oughta be able to surround the cone with a mess of wind-powered electric generators. Yes?

Marijn
Aug9-04, 06:43 AM
Hmmm, ok.
Assuming this works.
Pumping in tons of water into a vulcano (generally an elevated object in relation to sealevel) would take so much power that your "generator" wouldn't become profitable (in supplied energy) for years, if ever.
Besides, putting up a lot of wind generators on a surface that has volcanic activity?
Even if it doesn't errupt it will still probably be subject to minor quakes, not a really stable ground.

And i seriously doubt the fact that it would work.
It probably would be easier to create a dome over the lower part of the bowl and using the steam created, thus in fact making a giant steam engine.

2 problems:
#1 the shear size of the project in $$
#2 a biatch of a place to do construction work.
If it can boil water, it certainly will be the toughest place to work for construction workers ever.

In other words, no go either.

The french and german solutions will prove the better ones in this type of powergeneration.

siliconhype
Aug28-04, 02:50 PM
There is an article in scientific american about using earths, or any other planets gravity to generate electricity. Its the august 2004 issuet called "fly by wire", it proposes a terther system which build electricity in the tether that connects two objects in space (satelites) .

This isnt thermodinamics+gravity... but it's a way...

Question, is there a way to transmit electricity from space to earth? i alsways wondered about wireless electricity transmission... ( i think lightning are not an option tho' ;)

chroot
Aug28-04, 05:35 PM
siliconhype,

Sure, you could use a microwave beam to trasmit the energy. Just make sure the pointing apparatus is fail-safe, or the beam could become a major hazard.

- Warren

megashawn
Sep2-04, 08:04 PM
As to the space tether, lets call O the planet, and ---T the tether.

If it looks like: O----T

so long as the tether itself is a conductor, which is grounded on earth, it shouldn't be any trouble to just use conventional methods to collect the energy.


As to the hole in the ground generator, I've got a few thoughts.

For one, can we dig down deep enough to boil water, without exposing lava? If you dug two shafts, one a drop point for the water, which turned generators via the water falling towards the earths core, and at the bottom the water was heated into steam, which returned up the second tube.

Could you not also turn turbines on the escape tube via the steam? As was mentioned, the hot enviroment would not allow it to condense back into water, so you could get a double effect.

I guess you could test this with two hoses and a glass or metal container. Hose A would be the water input, and turns a generator before it falls into the container. Hose B would be a steam vent for the boiled water. The container would be completly sealed, aside from the two hoses. The steam shouldn't be able to escape through hose a because of the constant input of water.

The only challenges I see to setting this up would be ensuring you are boiling off the water quicker then it is building up.

hitssquad
Sep2-04, 09:20 PM
There is an article in scientific american about using earths, or any other planets gravity to generate electricity. Its the august 2004 issuet called "fly by wire", it proposes a terther system which build electricity in the tether that connects two objects in space (satelites) .

Question, is there a way to transmit electricity from space to earth?Gravity is a static force. Neither energy nor power can be generated from it. The Scientific American article admits as much:


Of course, conservation of energy demands that there is no "free lunch." For instance, power is generated only at the expense of the satellite's altitude, which was originally achieved by expending energy in rocket engines. So it may seem at first glance as if EDTs merely exchange one kind of energy for another in a rather pointless exercise. In drawing power from the tether, the satellite would descend and require reboosting.... So why bother? The answer is that the tether system is potentially more efficient...(Electrodynamic Tethers in Space, By: Lorenzini, Enrico, Sanmartín, Juan, Scientific American (http://www.sciam.com), 00368733, Aug2004, Vol. 291, Issue 2)

HallsofIvy
Sep7-04, 11:35 AM
Hydro-electric plants get power from gravity all the time!

To answer the original question, there is no practical way to "transmit" energy. There is some theory about transmitting energy by micro-waves but with any large amount, you run into problems with the atmosphere disrupting it. There are also those who point to serious problems if an antenna transmitting large amounts of energy gets pointed slightly wrong! (Where is all that energy going to go if the transmitting wave hits your house instead of a receiver?)

mee
Sep10-04, 12:29 PM
In the game "sid meir's alpha centauri" one can play with what they call "bore holes" and play with geothermal energy in this way. These are holes that go down to where the rock is hot and produce power in this way much like what people are talking about here.

cincirob
Oct28-04, 05:38 PM
There a e already methods of harnessing energy from gravity (like from the flow of water), but not in very massive amounts. What if we drilled a very deep hole into the ocean (down to the extremely hot farthest reaches of the crust where water will evaporate easily) and set up a generator at the bottom?

cinci: Some of the heat at the center of the earth was caused by gravity, but that would have cooled long ago. The heat we get now is primarily from decay of radioactive materials.

Have a massive pipe connected from the ocean water to the bottom of the pit. The hole wont fill up with water if ventilate the steam to the air above the ocean (driven by the difference in pressure). Mineral Insulated cables could be run down to the generator. I'm talking extremely hot conditions here to allow the massive amount of water flow to evaporate ASAP.. we would actually be using the earth's heat as a driving force to return the water...

Law of Convservation remains unbroken.. because the steam that rises back up the hole has lost its potential energy from the deep pressures of the ocean and the gravity of the hole... and has given it to us.

There's already a thread on here that talks about harnessing energy from the bottom of the ocean, but not from BENEATH the bottom of the ocean. [!:)]

cinci: Harnessing the tides is possible. They are gravity driven.

physical1
Jun1-09, 06:56 AM
Hydro-electric plants get power from gravity all the time!



Sorry to bring back an old post, but no they do not get the power from gravity. They get the power from the Sun, which brought the water up to a higher level than previously.

xxChrisxx
Jun1-09, 10:23 AM
Sorry to bring back an old post, but no they do not get the power from gravity. They get the power from the Sun, which brought the water up to a higher level than previously.

Er.... what?

DaleSwanson
Jun1-09, 11:02 AM
Er.... what?

The Sun converts nuclear bonds into energy through nuclear fusion. The energy then travels to Earth where some of it warms water and causes it to evaporate. The warmed water vapor rises and gains gravitational potential energy. Eventually the water falls as rain and ends up at a higher elevation than it was at the start. As the water flows downstream to a lower elevation we force it to turn turbines to capture some of its energy.

Thus, the energy we get in hydroelectric plants comes from nuclear fusion in the Sun. Energy is conserved, at no point is it created or destroyed. Energy never comes from gravity, it is a force not a source of energy.

xxChrisxx
Jun1-09, 01:49 PM
I still find that an utter crock of a statement as by some level of abstraction all energy comes from the sun. Which although true is not really very helpful.

So purely from a practical point of view, all we care about is the gpe of the mass of water has, not how it got it in the first place.

russ_watters
Jun1-09, 05:53 PM
Really, it is a matter of where you draw your system boundary, so I wouldn't get too worked-up about either statement.

physical1
Jun2-09, 11:15 PM
I still find that an utter crock of a statement as by some level of abstraction all energy comes from the sun. Which although true is not really very helpful.


All energy comes from the sun? I think your statement is crock. When nuclear power plants split atoms, this power is coming from the sun? Or is it coming from the mass that big bang somehow put here? was the sun responsible for that mass being "here" in the first place?

Does our electricity that a generator produces come from the magnets then - since they have potential being rubbed off em kind of like how gravity pulls things out of place.

Really, I am just being pedantic and posting statements to create heated arguments.

russ_watters
Jun3-09, 12:36 AM
Really, I am just being pedantic and posting statements to create heated arguments. That's the definition of trolling. Please stop.

xxChrisxx
Jun3-09, 05:35 AM
All energy comes from the sun? I think your statement is crock. When nuclear power plants split atoms, this power is coming from the sun? Or is it coming from the mass that big bang somehow put here? was the sun responsible for that mass being "here" in the first place?

Does our electricity that a generator produces come from the magnets then - since they have potential being rubbed off em kind of like how gravity pulls things out of place.

Really, I am just being pedantic and posting statements to create heated arguments.


Not to feed you or anything but, the most important bit of the statement was "...by some level of abstraction...". So in reality you can keep tracing 'how the energy got there' through some bloody tortuous path to get it back to the sun/universe/whatever. As Russ said where do you draw the boundary.

The point was that from a design point of view that is totally useless to know what the energy has done in the past. Making a machine to harness stored gpe, i'll use the practical and simple notion that yes the energy does indeed come from gravity (gpe) as it is the most convenient starting point for a design.

andrewbb
Jan20-10, 10:12 PM
What about getting the water up through evaporation/boiling and then harnessing the water flow on the way down?

dr dodge
Jan25-10, 01:29 PM
technically, neither the sun, nor gravity could do it alone, so we can say neither is directly responsible for the process alone.
but, gravity is the force we are worried about for engineering purposes. we can control getting water to the power plant, but not the force exerted upon it.

dr

andrewbb
Jan25-10, 01:42 PM
In my mind, the problem to focus on is maximizing the capillary action to pull fluids up through gravity. Then condensing the fluid to harness the flow on the way down. A miniature rain machine.

MiguelQ
Jan30-10, 04:46 PM
it would be better to have a big satellite orbiting earth and harvesting solar power, and sending it wireless to a receptor, that would distribute electricity to the earth homes...

i think electrity companies donnt want that of course to happen. free energy EHEH noo..

andrewbb
Jan30-10, 05:25 PM
it would be better to have a big satellite orbiting earth and harvesting solar power, and sending it wireless to a receptor, that would distribute electricity to the earth homes...

i think electrity companies donnt want that of course to happen. free energy EHEH noo..

Is that possible? Not a bad idea.

However, I do have a business plan for utility and oil companies that will work with this energy machine. Both types of companies will be very profitable.

Here's the idea in a nutshell:
- intramolecular forces are the root of thermal motion and kinetic theory
- strength of intramolecular forces is a function of temperature
- fluids leveraging natural evaporation/condensation will carry water up against gravity
- harnessing energy from gravity is then possible

This in no way is a perpetual energy machine nor does it break any laws of thermodynamics. With respect to thermodynamics, gravity is frequently ignored in most analyses of kinetic energy.

Redbelly98
Jan30-10, 05:31 PM
What about getting the water up through evaporation/boiling and then harnessing the water flow on the way down?
Because of the first law of thermodynamics. It would consume energy to evaporate/boil the water. You could never get more energy out then what is put in. It's easiest to let the sun to the evaporating.

In my mind, the problem to focus on is maximizing the capillary action to pull fluids up through gravity. Then condensing the fluid to harness the flow on the way down. A miniature rain machine.
It would take energy to remove the water from the top of the capillary tube.

To paraphrase Homer Simpson: "In this forum, we obey the laws of thermodynamics."

andrewbb
Jan30-10, 05:52 PM
Because of the first law of thermodynamics. It would consume energy to evaporate/boil the water. You could never get more energy out then what is put in. It's easiest to let the sun to the evaporating.

It would take energy to remove the water from the top of the capillary tube.

To paraphrase Homer Simpson: "In this forum, we obey the laws of thermodynamics."

The energy to condense water comes from intramolecular forces (hydrogen bonding).

Removing the water from the top of the capillary tube is performed by gravity.

Don't forget about the force of gravity in perceived thermodynamic limitations.

Consider: increasing the condensation rate of water vapor by electrifying a condensation rod. That uses a very slight amount of energy and leverages already existing intramolecular forces (hydrogen bonding). Once a water droplet forms, gravity pulls it off that rod. Imagine that water droplet accelerating as it falls 20m. The energy in that moving water droplet is greater than the tiny current required to attract a few water molecules out of the air. With some intelligent choice of materials (maybe silver iodide) that leverage the pre-existing hydrogen bonding tendencies of water and you wouldn't even require a current.

xxChrisxx
Jan30-10, 05:54 PM
Because of the first law of thermodynamics. It would consume energy to evaporate/boil the water. You could never get more energy out then what is put in. It's easiest to let the sun to the evaporating.

It seems to me that people constantly confuse 'free energy' that breaks the laws of thermodynamics, and energy that costs nowt. (ie is 'free')

Redbelly98
Jan30-10, 09:10 PM
It seems to me that people constantly confuse 'free energy' that breaks the laws of thermodynamics, and energy that costs nowt. (ie is 'free')
Yes, perhaps I was misunderstanding what was being said/meant earlier.

The energy to condense water comes from intramolecular forces (hydrogen bonding).

Removing the water from the top of the capillary tube is performed by gravity.
Here is my problem with that: if the force drawing the water into the capillary is stronger than gravity, then gravity is too weak to remove the water from the tube. And if the capillary force is weaker, then the water will not move up the tube in the first place.

Don't forget about the force of gravity in perceived thermodynamic limitations.

Consider: increasing the condensation rate of water vapor by electrifying a condensation rod. That uses a very slight amount of energy and leverages already existing intramolecular forces (hydrogen bonding). Once a water droplet forms, gravity pulls it off that rod. Imagine that water droplet accelerating as it falls 20m. The energy in that moving water droplet is greater than the tiny current required to attract a few water molecules out of the air. With some intelligent choice of materials (maybe silver iodide) that leverage the pre-existing hydrogen bonding tendencies of water and you wouldn't even require a current.
I have never heard of doing this. Do you have any references, or a link showing an actual working demonstration of this? Also, does "electrifying" mean applying a voltage & creating an electric field, or passing a current through the rod, or something else?

andrewbb
Jan30-10, 09:15 PM
Here is my problem with that: if the force drawing the water into the capillary is stronger than gravity, then gravity is too weak to remove the water from the tube. And if the capillary force is weaker, then the water will not move up the tube in the first place.


Capillary force is determined by the electromagnetic charges of the molecules. Different molecules have different strengths, so you could have a 2 material tube. Strong at first that pulls up, slope down on the weaker strength tube and gravity will overcome the cohesion.


I have never heard of doing this. Do you have any references, or a link showing an actual working demonstration of this? Also, does "electrifying" mean applying a voltage & creating an electric field, or passing a current through the rod, or something else?

No references. It's an idea I had about 4 weeks ago and am researching now. Given that hydrogen bonds are essentially a magnet, this seems doable. FYI, I do consider hydrogen bonds as the same force governing "capillary action". Just on the molecular level.

xxChrisxx
Jan31-10, 08:49 AM
Capillary force is determined by the electromagnetic charges of the molecules. Different molecules have different strengths, so you could have a 2 material tube. Strong at first that pulls up, slope down on the weaker strength tube and gravity will overcome the cohesion.

No references. It's an idea I had about 4 weeks ago and am researching now. Given that hydrogen bonds are essentially a magnet, this seems doable. FYI, I do consider hydrogen bonds as the same force governing "capillary action". Just on the molecular level.

I really mean no offence by this but... what utter crap.

The single biggest overriding factor that governs capillary action is having a very narrow tube and the relative pressures at either end.

Water isn't attracted by 'magnets' like you are thinking becuse it has a dipole, the attraction has to be induced and water has extremely low permeability. (Ie it doesn't magenetise well.)


There is much much more interesting (similar) thing being done like this already. It uses a membrane and salt and fresh water. Due to the different concentrations the water crosses the membrane by osmosis raising the levels and forcing the water up and through a nozzle that drives a turbine.

Only really any good if you live next to a river and the sea but, it's pretty cool.
http://news.bbc.co.uk/1/hi/world/europe/8377186.stm
I'm trying to find the video I saw of it.

Redbelly98
Jan31-10, 09:07 AM
Capillary force is determined by the electromagnetic charges of the molecules. Different molecules have different strengths, so you could have a 2 material tube. Strong at first that pulls up, slope down on the weaker strength tube and gravity will overcome the cohesion.
Where gravity overcomes the capillary force, the water will stop rising in the tube. It won't make it to the top.
No references. It's an idea I had about 4 weeks ago and am researching now. Given that hydrogen bonds are essentially a magnet, this seems doable. FYI, I do consider hydrogen bonds as the same force governing "capillary action". Just on the molecular level.
Hydrogen bonds are not "essentially a magnet", they are electrostatic in nature.

To put things nicely but honestly, it sounds like you do not actually understand the science behind what you are proposing.

andrewbb
Jan31-10, 08:20 PM
Um.... what do you think "dipole" and "electrostatic" are? They are forms of ELECTROMAGNETISM.

Why do you think water molecules form hydrogen bonds? The negative charge of the O is attracted to the positive charge in the H. That's essentially a magnet my friends.

Why is water attracted to its glass container? Well.. take a look at the structure of a molecule of glass. Lots of H's my friends. What is attracted to those H's? Why that would be the O's in the water molecules.

Why does water evaporate most quickly in butane? Again... take a look at a butane molecule. A few C's surrounded by a bunch of H's. What is attracted to those H's? Well a bunch of O's in water molecules.

It is YOU that doesn't understand the science. Why don't YOU explain water cohesion and its attraction to glass? If you use "dipole" or "electrostatic", please look up the words first.

xxChrisxx
Feb1-10, 08:13 AM
Um.... what do you think "dipole" and "electrostatic" are? They are forms of ELECTROMAGNETISM.

Why do you think water molecules form hydrogen bonds? The negative charge of the O is attracted to the positive charge in the H. That's essentially a magnet my friends.

'Essentially' a magnet. Do you know what permeability is? Water has a similar permeability to air and aluminium. They don't respond to regular strength magnets, and neither does water.

andrewbb
Feb1-10, 07:46 PM
'Essentially' a magnet. Do you know what permeability is? Water has a similar permeability to air and aluminium. They don't respond to regular strength magnets, and neither does water.

Individual molecules act as tiny magnets with each other, but the effect is not additive across chains of hydrogen-bonded molecules.

EDIT: water molecules are affected by electromagnetic fields. EG. microwaves will spin the molecules.

DaveC426913
Feb1-10, 07:58 PM
Why is water attracted to its glass container? Well.. take a look at the structure of a molecule of glass. Lots of H's my friends. What is attracted to those H's? Why that would be the O's in the water molecules.

Why does water evaporate most quickly in butane? Again... take a look at a butane molecule. A few C's surrounded by a bunch of H's. What is attracted to those H's? Well a bunch of O's in water molecules.
Did you learn this chemistry in school or are you going on your own deductions?

xxChrisxx
Feb1-10, 09:23 PM
Individual molecules act as tiny magnets with each other, but the effect is not additive across chains of hydrogen-bonded molecules.

EDIT: water molecules are affected by electromagnetic fields. EG. microwaves will spin the molecules.

This is all just mental masturbation. You try to 'suck' water up using a magnetic field it WILL fail. Water just doesn't magnetise, that is really as simple as it gets. You can use magnets to polarise molecules (a la NMR machines), but this is a very far cry from acutally moving molecules with them.

Applying a strong magnetic field does have a very small effect on the surface tension. By stong I mean on the order of 100000's gauss to give small percentage changes in surface tension.

Top marks for creative thinking. However like all things, creative thinking and pratical useage are worlds apart.

andrewbb
Feb1-10, 09:58 PM
This is all just mental masturbation. You try to 'suck' water up using a magnetic field it WILL fail. Water just doesn't magnetise, that is really as simple as it gets. You can use magnets to polarise molecules (a la NMR machines), but this is a very far cry from acutally moving molecules with them.

Top marks for creative thinking. However like all things, creative thinking and pratical useage are worlds apart.

I agree. You won't suck up water using magnetism. But individual molecules do respond to electrical charge.

The strength of the charge of a single molecule is a function of where the electrons are in relation to the protons. On water, the hydrogen atoms' electrons are covalently bonded to the Oxygen so the Hydrogen's protons' positive charge is exposed. Since there are 2 un-bonded electrons on the Oxygen, that side is negatively charged and can attract the Hydrogen side of another water molecule. That attraction is electromagnetic, but the effect is certainly not additive, so hydrogen-bonded water molecules are not going to form a magnet.

At high temperatures, the above is not a huge effect because hydrogen bonds are weakened, however at room temperatures, this effect is important. I am trying to find ways to accelerate condensation of water vapor at room temperature.

MiguelQ
Feb3-10, 08:37 AM
look water is magnetized like matter is.. just check those videos on youtube with high power magnets and you will se water foating like zero-G

dr dodge
Feb4-10, 11:47 AM
and we all know no one fakes stuff on utube
like the cell phone popcorn thing
somehow the idea of a magnet that strong brings the image to mind of the coyote road runner cartoons, where the coyote shallows the magnet, then everything magnetic comes chasing after him

dr

Redbelly98
Feb4-10, 07:27 PM
look water is magnetized like matter is.. just check those videos on youtube with high power magnets and you will se water foating like zero-G
Water's relative permeability, according to Wikipedia (http://en.wikipedia.org/wiki/Permeability_%28electromagnetism%29#Values_for_som e_common_materials), is only μ/μ0=0.999992

If you're going to make fantastic claims, at least post a link to "those videos" so we have something to critique.

Doug Huffman
Feb4-10, 07:35 PM
Theres already methods of harnessing energy from gravity (like from the flow of water), but not in very massive amounts.

The highest capacity power plant in the world is the Three Gorges complex currently above 20,000 MW of hydroelectric power.

The water mass of the complex is so great that it has bent the Earth's crust.

dr dodge
Feb5-10, 07:17 AM
thats from its mass, not its magnetism

dr

xxChrisxx
Feb5-10, 07:28 AM
Water's relative permeability, according to Wikipedia (http://en.wikipedia.org/wiki/Permeability_%28electromagnetism%29#Values_for_som e_common_materials), is only μ/μ0=0.999992

If you're going to make fantastic claims, at least post a link to "those videos" so we have something to critique.

He's going to link the levetating frog. Not realising that it's BECAUSE water has a low permeability (ie it's a diamagnet) that it levetates which isn't the same as magnetising it. It also required enormous field strengths.


On a different note, I believe I misread what andrewbb was talking about (just reread the thread). The talk of capillary action made me thing he was trying to increase that effect by magnetism :redface:. Not that just a charged rod would encourage condenstation. Which i've never head of, but don't know enough about to comment.