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Freely maintained water transfer

  1. Aug 15, 2003 #1
    freely maintained water transference

    Hello again.

    Just a little and simple question, i think you'll see what i mean:

    Imagine a full tank of water 1m long. This tank has a spring behind, compressed by the water weight on top. This spring is 1m long from the ground, so the water is at 2m from the ground.

    Imagine another empty tank of the same dimensions. This tank has another spring behind, but as the tank has no water, the spring is uncompressed. This uncompressed spring is 2m long from the ground, so the tank is at 2m from the ground.

    The two tanks are connected, but as the water level on one tank is the same as the ground on the other, no transference happen.

    Now, you compress a part of the uncompressed spring, say 0.2m from the ground to 0.1m. This effect is the same that a water level of 0.1m will cause.

    Now, the ground of the empty tank is 0.1m behind the water level of the full tank (because you compressed the spring, but not with water weight), so a water transfer starts.

    the sequence now happens like this:

    A-water...A-spring...A-total....B-water...B-spring...B-total

    1m........1m.........2m..........0m........2m.........2m
    1m........1m.........2m..........0m........1.9m.......1.9m
    0.9m......1.1m.......2m..........0.1m......1.8m.......1.9m
    0.8m......1.2m.......2m..........0.2m......1.7m.......1.9m
    . . . . . .
    . . . . . .
    0.2.......1.8m.......2m..........0.8m......1.1m.......1.9m
    0.1m......1.9m.......2m..........0.9m......1m.........1.9m
    0m........2m.........2m..........1m........1m.........2m

    As you can see, we apply the force of 0.1m of water weight to the spring to start the proccess , and obtain 10 times (1m) the transference of this water.

    If the tanks were 50 times longer (5m) than the equivalent water energy input (and supposing the springs could follow the same changes), then we will get 50 times the transference of the initial equivalent water.

    I mean, you can apply the same work to start, and have a longer or shorter transference between the tanks, independent of the initial energy input. The transference depends of the kind of tanks and springs.

    So, as energy input is independent of the proccess, what avoid us to get more energy from the proccess than the needed to start it again to the other hand?.

    For example, a turbine connecting behind the tanks will collect the energy from the transference, and later we could use this energy to compress a part of the spring to start the proccess again.

    Of course, the turbine will oppose to the transference in some manner, but if the initial level difference of the water tanks is big enough, this opposition can be bypassed, and start the proccess.

    At this point, the energy input needed is only to pass the turbine opposition. Once the turbine start to work, the transfer is maintained at the same water levels, and this transference could be for a long time, obtaining several times the energy needed to start it.

    Any question?
     
    Last edited: Aug 15, 2003
  2. jcsd
  3. Aug 15, 2003 #2

    Integral

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    Why not build one?
     
  4. Aug 15, 2003 #3
    HAHAHA

    JUST BUILD IT !

    Will i obtain that SAME answer ALWAYS ?

    Is that the way you explain physics ?

    This time the concept is very very easy to understand, no zero point virtual particles, no time reversal, no quantum physics or relativity, just two tanks, two springs and water.

    I'm not interested on how it works... i'm interested on see how do you explain it wont.
     
  5. Aug 15, 2003 #4

    russ_watters

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    This is debunked somewhere else on this site. Can't remember where.

    The real purpose of that example is to make the issue more complicated than it really is, thereby making it harder to debunk.

    If you want the scientific explanation, go look for it. But Integral is right: the issue really is if YOU think it works, then YOU should build it. It doesn't require debunking since there is nothing to debunk since you can't build one that works.

    Its what I like to call "self-debunking."
     
  6. Aug 15, 2003 #5
    As i said to Integral

    ...You explained NOTHING

    If it doesn't work, i'm asking WHY.

    Is this a physic forum or WHAT??
     
  7. Aug 15, 2003 #6
    russ: The proposse of this post is just the opposite you said.

    I talked before about tanks and springs on another topic, but now I think this method is more easy to understand, getting the same effects.

    So it is to make it simple.

    And the topic was not debunked, finally, no one talked about it any more. We reach the JUST BUILD IT point.


    If i asked you how or why an electric motor work... would you tell me JUST BUILD IT?...I'm not from GENERAL MOTORS INC.
     
  8. Aug 15, 2003 #7

    Bystander

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    Cala-

    The first and second laws of thermodynamics are your first clues that you have done an INCOMPLETE analysis of your designs for energy/power producing contraptions. It is your responsibility to do the COMPLETE energy calculations for ALL steps in the processes you propose.

    Do this much at least, and present your calculations in detail, or, "BUILD IT!"
     
  9. Aug 15, 2003 #8

    russ_watters

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    I would explain it of course. But you are not asking how something works, you are asking us to prove to you why something you believe works does NOT work. Big, big difference.

    The first is a desire to be educated, the other is a desire to AVOID being educated since you already have your conclusion. The fact that you continue to try and come up with new ways to avoid the first law of thermodynamcs shows you have no desire to learn.

    So it really is useless to argue with you. We explained why already and you simply won't accept it.

    People have been designing and building self-powered water wheels for centuries. The first (on record) in fact was what lead to the discovery of the first law of thermodynamics. Not one has ever worked, but the US Patent Office continued to get submissions. The patent office adopted the position (and this is where I got the position from) that since the science behind this is well understood, no patent application will even be accepted for review until such a device has been shown to run unpowered for a year.

    Essentially though (I'll throw you a bone, though we alredy told you and you ignored it), there are two flaws in your reasoning (and for that matter every other perpetual motion machine ever designed).

    1. You improperly use the potential energy level of the initial state in each iteration including the first. That's the 1st law of thermodynamics.

    2. You ignore losses. Thats the 2nd law of thermodynamics.

    The 1st law problem here is quite simple. The initial state has some potential energy: x. At the beginning of the next iteration, you have the same initial state and thus the same potential energy: x. The maximum amount of energy that can be generated by the system is x-x=0. Everything in betweeen the two initial states is smoke and mirrors designed (either by accident or on purpose) to cloud this simple equation.
     
    Last edited: Aug 15, 2003
  10. Aug 15, 2003 #9
    cala,

    When you push down on empty tank A
    (compressing its spring) such that
    its bottom is below the water level of the full tank B, water
    will start to flow from the full
    tank to the empty tank. If you
    maintain compression of tank A's
    spring at that level the full
    tank B will slowly rise as the weight on it decreases and more
    of its water will run into tank A.
    Eventually they will reach equi-
    librium with each half full. At
    this point water transfer will
    stop.

    You have, however, not harvested
    more energy from this than you
    put into it. It required energy to
    put water into the full tank to
    begin with and most of what you
    get out is simply the release of
    this energy that has been stored
    in the full tank's compressed
    spring. In addition you have to
    apply force to compress the spring
    beneath the empty tank and to
    maintin that force untill equi-
    librium is reached.

    -Zoob
     
  11. Aug 16, 2003 #10
    Hello zoob, you're right:

    "You have, however, not harvested
    more energy from this than you
    put into it. It required energy to
    put water into the full tank to
    begin with and most of what you
    get out is simply the release of
    this energy that has been stored
    in the full tank's compressed
    spring."

    Yes, but you can use this energy once and again from the transference of water from one tank to another. The springs store or bring energy meanwhile the water transference happen.

    "In addition you have to
    apply force to compress the spring
    beneath the empty tank and to
    maintin that force untill equi-
    librium is reached."

    Yes, you apply an initial work to compress part of the empty tank spring, but when you reach the compression point, you keep the force, but you don't make work any more.
     
  12. Aug 16, 2003 #11
    Yes, but you can use this energy once and again from the transference of water from one tank to another. The springs store or bring energy meanwhile the water transference happen.

    Cala,

    You can use the energy stored in
    the spring once, but once you have
    used it it is not possible to use
    it again. This is because "using"
    it means turning it into work.

    If you use the water flowing from
    one tank to the other to run a
    turbine to generate electricity
    then the energy of the compressed
    spring is now electrical energy.

    The amount of this electrical en-
    ergy will never be equal to the
    original work it took to put water
    into the tank to begin with and
    compress the empty tank's spring.
    You will have lost some energy to
    friction/heat, sound, vibration.

    You will be able to replace some
    of the water but not all. The
    second cycle will produce less
    electrical energy than the first.

    Each cycle will produce less elec-
    tricity untill the thing stops
    running. In the meantime all it
    has accomplished is to run itself.
    In conclusion all you have done
    is to create a very awkward kind
    of pendulum.

    zoob
     
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