Golden ratio - Irrational Mathematical Constant

Discussion in 'Boat Design' started by Frog4, Oct 23, 2011.

  1. Frog4
    Joined: Oct 2011
    Posts: 150
    Likes: 2, Points: 0, Legacy Rep: 12
    Location: Arizona desert

    Frog4 Proletariat

    The Golden Ratio - How many designers use this in their designs?
     
  2. daiquiri
    Joined: May 2004
    Posts: 5,372
    Likes: 245, Points: 73, Legacy Rep: 3380
    Location: Italy (Garda Lake) and Croatia (Istria)

    daiquiri Engineering and Design

    No golden ratios in naval architecture. Physics, not alchemy, is what governs a ship design.
     
  3. kerosene
    Joined: Jul 2006
    Posts: 1,045
    Likes: 60, Points: 48, Legacy Rep: 358
    Location: finland

    kerosene Senior Member

    it is not _bad_ tool for certain styling proportion choices but really - in most cases trained eye does a better job. It is one of those things that when analyzing has been afterward forced to fit many successful designs/artwork.

    Similar to the kind where you add Hitlers birth date and death date multiply by this and divide by that and you get 666!!!! or something. or those silly facial proportion pentagram things you might have seen in documentaries about beauty.

    Certainly the same ratio and Fibonacci sequence 1,2,3,5,8,13,21...(consecutive numbers have same ratio as golden section) do show up a lot in nature. Interesting but wouldn't let it make very big decisions.
     
  4. Adler
    Joined: Jan 2010
    Posts: 162
    Likes: 14, Points: 18, Legacy Rep: 139
    Location: PIRAEUS - GREECE

    Adler Senior Member

    Navy

    Dear All,

    We observed, that on Navy Ships the General Dimensions (Monohull-SemiDisp/Displ - round bilge)
    appears a strong relation between LOA and Beam that based in a function (regression 0.97)
    where the constant ϕ is involved:

    LOA= (B^F) /ϕ where F=ϕ^ϕ and for ϕ=1,61803398874989
    then F= 2.17845756793758
    .

    The matter comes from dreadnought type to nowadays.
    We have to note that as Frog4 put the subject on the table.
     
  5. Adler
    Joined: Jan 2010
    Posts: 162
    Likes: 14, Points: 18, Legacy Rep: 139
    Location: PIRAEUS - GREECE

    Adler Senior Member

    Diagram

    Regarding the matter please see the attached.
     

    Attached Files:

  6. Frog4
    Joined: Oct 2011
    Posts: 150
    Likes: 2, Points: 0, Legacy Rep: 12
    Location: Arizona desert

    Frog4 Proletariat

    was also thinking about the 80-20 rule (Pareto Principle), 10% Rule and the 3's and 5's rules within design ...
     
  7. rwatson
    Joined: Aug 2007
    Posts: 5,852
    Likes: 288, Points: 83, Legacy Rep: 1749
    Location: Tasmania,Australia

    rwatson Senior Member

    Which Navy - how many ships ?

    Did you include Aircraft carriers ?
     
  8. Lister

    Lister Previous Member

    Lister

    [​IMG]
     
  9. Adler
    Joined: Jan 2010
    Posts: 162
    Likes: 14, Points: 18, Legacy Rep: 139
    Location: PIRAEUS - GREECE

    Adler Senior Member

    Round bilge:

    Patrol Boats - Torpedo Boats (Lurssen Schnellboote) - Frigates - Destroyers - Battle Cruisers

    with LOA up to 180m.

    The Aircraft carriers is a combined ship + platform that has completely different
    purpose of design.
    Actually strikes with her Aircrafts and not by her arms and has no ability to hunt.
     
  10. rwatson
    Joined: Aug 2007
    Posts: 5,852
    Likes: 288, Points: 83, Legacy Rep: 1749
    Location: Tasmania,Australia

    rwatson Senior Member

    The Pareto Principle isn't a design rule like the Golden Ratio, its a statistical principle that may apply to aspects of design

    eg 20% more HP will give 80% better fuel economy.
     
  11. daiquiri
    Joined: May 2004
    Posts: 5,372
    Likes: 245, Points: 73, Legacy Rep: 3380
    Location: Italy (Garda Lake) and Croatia (Istria)

    daiquiri Engineering and Design

    Total and complete nonsense. Looks like you didn't even bother to check your theories against data of existing ships.

    Here is a capture of a spreadsheet with LOA and B data of several ship classes from various navies around the world, together with a graph where these data are shown as points. In the same graph there is a line given by your mystic formula. Now you tell me what relationship can you see between that line and the data from real ships?

    Golden Area Non-Rule.gif

    Your attachment lacks the connection with the real world - see the above graph.
     
  12. rwatson
    Joined: Aug 2007
    Posts: 5,852
    Likes: 288, Points: 83, Legacy Rep: 1749
    Location: Tasmania,Australia

    rwatson Senior Member

    Well done Daiquiri - I suspected that it was all too neat, hence my questions.
    There is no such thing as a simple solution in this complex world.

    For a more thorough discussion on the Golden Rule, the thread at

    http://www.boatdesign.net/forums/boat-design/placement-spacing-frames-38717-2.html

    might apply.

    Do you know the user CaptBill, Adler ?
     
    Last edited: Oct 23, 2011
  13. Frog4
    Joined: Oct 2011
    Posts: 150
    Likes: 2, Points: 0, Legacy Rep: 12
    Location: Arizona desert

    Frog4 Proletariat

    I think you should have asked;

    "where" the data came from?
    "Which" navy?
     
  14. rwatson
    Joined: Aug 2007
    Posts: 5,852
    Likes: 288, Points: 83, Legacy Rep: 1749
    Location: Tasmania,Australia

    rwatson Senior Member


    We did !!

     

  15. daiquiri
    Joined: May 2004
    Posts: 5,372
    Likes: 245, Points: 73, Legacy Rep: 3380
    Location: Italy (Garda Lake) and Croatia (Istria)

    daiquiri Engineering and Design

    The data in my spreadsheet come from existing ships from 4 actual navies and they clearly show that the "rule" and the following claim
    "We observed, that on Navy Ships the General Dimensions (Monohull-SemiDisp/Displ - round bilge) appears a strong relation between LOA and Beam that based in a function (etc...)"​
    has no basis in the real world, where physics and SORs (and not mystic ratios and formulas) are what determine the shape of a ship.
    If it's the form of my reply, and not the substance, that bothered you, then I'm sorry it has bothered you. Sometimes a person feels a need to double-underline his disapproval of unbacked and misleading claims.
     
Loading...
Similar Threads
  1. Santiago ARG
    Replies:
    1
    Views:
    5,640
  2. FAST FRED
    Replies:
    8
    Views:
    2,867
  3. thenavalarch
    Replies:
    1
    Views:
    271
  4. RyanBravada
    Replies:
    5
    Views:
    570
  5. wesley Sherman
    Replies:
    12
    Views:
    699
  6. thenavalarch
    Replies:
    0
    Views:
    308
  7. mustafaumu sarac
    Replies:
    4
    Views:
    795
  8. misanthropicexplore
    Replies:
    14
    Views:
    1,528
  9. ryanonthebeach
    Replies:
    41
    Views:
    2,567
  10. Ali Golshani
    Replies:
    0
    Views:
    557
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.