resistance test in wave conditions

Discussion in 'Software' started by apmc.1987, Mar 15, 2011.

  1. jehardiman
    Joined: Aug 2004
    Posts: 3,069
    Likes: 572, Points: 113, Legacy Rep: 2040
    Location: Port Orchard, Washington, USA

    jehardiman Senior Member

    Not sure what you mean by "negative eddy", but is has a lot on natural viscious mixing due to things like density layers, jet flows, and falling objects.

    Isn't "repeatable turbulence" an oxymoron? :D ....I mean if it is repeatable isn't it by definition a "vibration" no matter how long the period, i.e. a step function happens once and only once.....after that it is a periodic function....;)
     
  2. Leo Lazauskas
    Joined: Jan 2002
    Posts: 2,696
    Likes: 151, Points: 63, Legacy Rep: 2229
    Location: Adelaide, South Australia

    Leo Lazauskas Senior Member

    Yes it is, but I can't think of a better term for it. :eek:
    Maybe turbulence within a given fixed range of intensity would have been better.
     
  3. DCockey
    Joined: Oct 2009
    Posts: 5,025
    Likes: 513, Points: 113, Legacy Rep: 1485
    Location: Midcoast Maine

    DCockey Senior Member

    Or repeatable as far as the relevant probability statistics are concerned.

    Vibrations are generally considered to repeat with one or more fixed periods/frequencies. Of course if enough frequencies are considered any reasonable continuous but random function can be approximated to the desired level of accuracy.
     
  4. jehardiman
    Joined: Aug 2004
    Posts: 3,069
    Likes: 572, Points: 113, Legacy Rep: 2040
    Location: Port Orchard, Washington, USA

    jehardiman Senior Member

    Uncertainity actually, lol ;)

    I spent a lot of time wallowing around in that tar pit trying to predict peak motions and loads in waves...I wouldn't advise it. Better to use stoichastic spectral analysis and then walk away knowing you did your best.
     
  5. Leo Lazauskas
    Joined: Jan 2002
    Posts: 2,696
    Likes: 151, Points: 63, Legacy Rep: 2229
    Location: Adelaide, South Australia

    Leo Lazauskas Senior Member

    Uncertainty actually, pedantic lol ;)

    All I want is a way of producing reasonably consistent large values of the horizontal and vertical eddy viscosity in a tank.
    Maybe I should use a tar pit.
     
  6. jehardiman
    Joined: Aug 2004
    Posts: 3,069
    Likes: 572, Points: 113, Legacy Rep: 2040
    Location: Port Orchard, Washington, USA

    jehardiman Senior Member

    To paraphrase Fermi "If I could have spelt better, I would have been a writer." I blame the English school system where I learned my colours.
     

  7. DCockey
    Joined: Oct 2009
    Posts: 5,025
    Likes: 513, Points: 113, Legacy Rep: 1485
    Location: Midcoast Maine

    DCockey Senior Member

    Agree. I was commenting on the theory, not what is a reasonable approach.
     
Loading...
Forum posts represent the experience, opinion, and view of individual users. Boat Design Net does not necessarily endorse nor share the view of each individual post.
When making potentially dangerous or financial decisions, always employ and consult appropriate professionals. Your circumstances or experience may be different.