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Thread: How would water behave in heavy gravity?

  1. #1 How would water behave in heavy gravity? 
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    I understand that in lower gravity water would bounce around and be more gelatinous than what we're used to, but I can't find anything discussing water's behavior in a heavy gravity environment. Are there any articles or good descriptions out there of how water would look and act (coming out of a faucet or shower spray, for example, or rain, or rivers) in gravity significantly higher than Earth's gravity?
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  2. #2  
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    Look at videos of metal smelting, metal refining, metal casting and of mercury.
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  3. #3  
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    Thanks; I know what molten metal and mercury look like but they look rather watery when poured. Are you saying it would appear thicker/denser and less...splashy? Not exactly a scientific term, I know, but I'm just trying to figure out what properties it would exhibit. For example, what might happen if someone stepped into a pool of water in heavy gravity? Or how would it look coming out of a shower head, especially in relation to how it runs down the body or through the hands under a faucet? Would it sort of just roll right off in large, heavy, fast-falling globs? What happens when it hits the floor?

    Any resources on the subject or detailed descriptions of how water would look/feel/act in heavy gravity would be greatly appreciated. Like I said, I've been fascinated by reading about water in low gravity but I can't find anything at all about it in a higher gravity environment and I'm extremely curious.
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  4. #4  
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    Increased gravity will not make liquids thicker, denser or more viscous or increase the bulk modulus
    I am not talking about neutron star gravity. I am talking 10g stuff like that. And I am speculating a bit.

    A case for denser can be made for oceanic depths of water but that is a function of hydrostatic head that can be simulated by depth, pumps, diamond anvils. And the increase at oceanic depths is one percent or so.

    For rain, in greater gravity will water have a greater terminal velocity or will air resistance and turbulence atomize the drops to droplets to vapor.

    Will the ballistics of a fire hose size stream be different. Consider mgh = 1/2 mv^2.

    How will a siphon work. A siphon relies on the cohesion of water. It works in a vacuum and it has nothing to do with differences in air pressure between the high and low ends. A siphon will likely work faster.

    What about the traps in drains? Would they be the same? Trick question, maybe?

    As for getting more gelatinous at zero g. I think that is an illusion. Jello and ballistic gelatine are tenacious, resilient and quite sold. A blob of water can be atomized with a slap of the hand.

    I am sure there are computer simulations that are available on youtube for you to find.
    Last edited by pikpobedy; 09-19-2014 at 10:33 AM.
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  5. #5  
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    Hmm thanks but I've looked on youtube and all throughout google and can't seem to find anything. I can only find information on water in low gravity and then information regarding "heavy water." I've found absolutely NOTHING related to the behavior of water in heavier gravity (I'm talking another planet with a heavier gravity than earth, nothing too extreme...sort of the opposite of what the moon is to earth gravity-wise). If there are any simulations or articles out there, I'd love to know, but I haven't been able to find any yet.
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    You can start with a simple surface wave. The speed of a wave is related to

    , where h is the height of the wave. So in on a high gravity world, waves would travel faster.

    If you are considering something like a ocean wave coming up on a beach this is a "compression wave". Compression waves have the characteristic that the trailing edge is higher than the leading edge. Since the speed of the wave depends on the depth, the higher trailing edge travels faster than the leading edge, causing the wave to steepen. when it gets steep enough, it "breaks".

    So let's compare two waves, with both the trailing edge is 1 unit behind the leading edge. the leading edge is at h=1 and the trailing edge at h=2.

    Setting g to 1 we find that it takes a time of

    = 2.414 for the wave to break. In which time, the leading edge will have traveled a distance 1 x 2.414 = 2.414

    Now setting g to 10 for the same starting conditions, it takes a time of

    = 0.7634 for the wave to break. In which time the leading edge will have traveled 3.162 x 0.7634 = 2.414.

    So while the wave travels faster and breaks more quickly, the distance it travels before breaking is the same. So breaking waves of a given height at 10g basically behave like the same waves at 1g running at 3.162 times the speed.
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