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How would this preform

  1. Jul 6, 2011 #1
    If i built a vessel shaped as a water molecule and made it neutrally buoyant with a counter sink (for stability and upright)- How would this preform in the ocean?
    how would it act in high seas?
    would it pass through a wave on a compressed arc or over it near its surface?
    what would the reduction of speed be in comparison to a convential boat?
    In the perfect storm (like the movie) would you be safer on a convental boat trawler etc.
    or in a water molecule vessel of same size?
  2. jcsd
  3. Jul 6, 2011 #2


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    You mean shaped like this? Kind of a goofy looking boat, eh? [PLAIN]http://www.drymaxsocks.com/images/H2OMOLECULE.jpg [Broken]
    Last edited by a moderator: May 5, 2017
  4. Jul 6, 2011 #3
    Are you thinking that because the boat is shaped like a water molecule and neutrally buoyant that it will behave just like all the other real water molecules around it? If so, you are wrong. Physics is not scale-invariant. A machine built at human size and an identical one built at bacteria size will not operate the same. One of example of this is surface to volume ratios. The surface area of a sphere is proportional to its radius squared while its volume is proportional to its radius cubed. A sphere's surface-to-volume ratio is 3/r. This means that bigger spheres have less surface area relative to their volume. That's why small drops of water hold their shape well due to surface tension despite gravity, but large drops of water do not.
  5. Jul 6, 2011 #4
    My apologies all, (a bit about me- after a head injury everything (my memory) is mixed, jumbled, or missing, so most things have to be relearned (the joke is that i don't retain anything for more than a few days), I've been told that I was a inventor and even though i don't remember some things won't let you go (I hope no one else ever understands this statment).
    I need a house (due to my condition) and wish to give my wife, who has never been anywhere outside a small town, her wishes to travel the world.
    we have nothing but time, and in theory a floating house is ideal.

    I relise that i will have to engauge a professional engineer to make all final specs. However at this stage I wish to explore if this is possibly a resonable idea...

    attached is a design for a ocean going boat made out of lexan (bullet resistant plastic).
    I want to use lexan for a few reasons- it can be lamanited to itself to any thickness and still remain transparent (theorically the sphere can be 1m or more in thickness), it is light weight, it can be repaired with lexan, resin or other bonding agent, easy to clean, etc...
    the propolsion system etc... is omitted as its not needed.
    I am looking for a few things from the design (based on a sphere is the strongest shape)-
    size vrs space,
    sealed compartments,
    safety (impak, pressure etc...),
    Any rogue wave or high seas (storms etc...) will hit the vessel and instead of it cutting through the wave, it submerges under the waves force and resurfaces, (i realise that there is turbulance and vessel will spin and roll 360 degs) but act like a cork (as long as the structure doesn't fail the vessel has to resurface at some point- decompressing a air ballast tank can control this.
    If a room/compartment fails by cracking a dome shaped perspex can be sealed to the outside, the room pumped out and lexan or other resin can be utilised to make repairs.
    360 deg view, from anywhere onboard.
    A vessel that can be mored in a harbour and used for a house indeffently.
    A vessel that can withstand nature and extreem seas.

    the spheres need to be (ID) 2500mm min - However 3000mm is more to what we need to be comfortable.

    Attached Files:

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    Last edited: Jul 6, 2011
  6. Jul 7, 2011 #5


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    Are you serious? Why not just get or build a big boat and put a waterproof and airproof cover over it? It seems way easier and more realistic than building something like your example.
  7. Jul 9, 2011 #6
    To be serious- and i may be wrong (nothing new these days)
    If we placed both vessels under a perssure test I would bet your boat would structurally fail way before mine would, the lenght to width ratio of your ship would inherit a weakness in the center of the length... 1 reason for sealed bulkheads-
    the nose (bow?) of all ships must be placed into the wave or it can capsize or roll, storms through out history has sunk the design.
    If you know of any structural flaws (inherit or other), or other reason- design, sanity, etc... please give details.
    I think there is some skill and knowledge needed to navagitate a ship safe & effictively with this increasing with a deteriating weather pattern.

    Could being pushed around like a propelled cork (my design) be a improvement?
    Could seniero's and possible mistakes etc.. that will sink a ship, sink my design?
    Any debate on subjects is welcome.

    Attached Files:

    Last edited: Jul 9, 2011
  8. Jul 9, 2011 #7


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    Do you really think you are up to something like this after a head injury? What if you miscalculate or forget something?
  9. Jul 9, 2011 #8
    anything is possible.
    any one can miscalculate or forget- a engineer will have final say over specs
    I hope he gets it right... also there is no harm of me using this as a mental exercise in design (which has resulted in a question "how would this preform" )
    based on this design as long as the hatch is sealed then the vessel for arguement is a "cork" sustaining being submerged by force of any wave breaking on it, any chance of a rogue wave, storm wave broad siding the vessel or forcing it under the surface by kenetic energy of white wash is accounted for even though it may be a wild ride...
    as to the rest of it all I rely on my wife every day to remember and she as well has great interest in this and want to learn... by her reading these posts and others she is beginning to understand more of everything.

    I guess the sub questions are now- is this a safer design (than a yaucht, or cruiser),
    based on the principals of physics would it preform better or worse than conventional "boats" (when subjected to weather, drag, saftey, speed, preformance, etc...)
    If your responce is to only question my preformance, I guess my design has potiential...
    I'm only guessing- LOL.
    Last edited: Jul 9, 2011
  10. Jul 9, 2011 #9
    Hi I'm wifey im interested in this all
    i am skeptical about most of this project all i know is corks float
    my questions are (assuming we dont hit the bottom of the sea) what are the benifits of a boat over this design
    what is the kenetic energy of white wash
    why do these boats and ferries on the news sink and what would sink my husbands design- he says the only ways his design will sink is if the hatch is left open or 3 or more of the spheres break
    could we get the bends if we go to far under water my husband says no because the lexan and shape will not compress enough and we will assend at the same rate as any bubble same as diving precautions
    he says the spheres outside a control sphere will be pressurised it will be pumped in if we are submerged to long, he says it wont reduce the boyancy of the boat as the other rooms spheres heavier and when the air is decompressed they become lighter- is he right and why
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