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Community and Q&A

Fun With Fluids

homedesign | Posted in Energy Efficiency and Durability on

(starting 1:30 minutes into this video)
Thorsten Chlupp mentions a fascinating concept …Stratification

It seems we can “store” a not-so-dense fluid above a dense fluid….

It’s kind of Intuitive that a dense fluid will support a not-so-dense fluid.

What’s Not so Intuitive is that the “fluids” might be in very distinct layers.
…separated by “Internal Waves”….

similar to this demonstration

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  1. homedesign | | #1

    I'm not advocating for water storage tanks in all buildings or for all climates.

    It's the distinct stratification of Fluid Layers that I find interesting.
    (Air is also a fluid)

  2. user-659915 | | #3

    Takes a steady hand...

  3. GBA Editor
    Martin Holladay | | #4

    This is observable any time you go swimming in a Vermont lake in June. Just dive down and feel the stratification.

    Without thermal stratification, tank-type water heaters wouldn't deliver hot water.

  4. user-659915 | | #5

    I experienced a small earthquake in Greece one time. It was August. The next morning the top layer of the Aegean was icy cold. Took three days to return to its normal balmy state.

  5. homedesign | | #6

    Hi James,
    I have looked at many of the fluid layering experiments
    where different fluids are stacked

    it also works with the same fluid at different temperatures

    A cool fluid can support a warm fluid
    A warm fluid can not support a cool fluid

    You can see the "Internal Wave" in the Hot over Cold example.

    I've also seen the boundary(between densities) referred as a thermocline
    the thermocline forms a physical barrier to mixing

  6. homedesign | | #7

    In Thorsten's example it's not surprising that the warmest water is at the top of the tank.
    For me's interesting that the warmest water remains in a VERY compact "zone"....
    and there can be a distinct boundary between zones.

  7. heinblod | | #8

    The laws of physics, always a note worth :)

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