NACA # for a long keels?

Discussion in 'Hydrodynamics and Aerodynamics' started by Howlandwoodworks, Jul 9, 2019.

  1. Howlandwoodworks
    Joined: Sep 2018
    Posts: 55
    Likes: 12, Points: 18
    Location: Columbia MO

    Howlandwoodworks John Howland

    I have made some changes to my keel.
    At the bottom of the drawing below is a new keel foil design for my boat of a 5% to 10% PMB 3/1 Ellipse LE, ?% Radius TE, 7% to 8% t/c (or to the best of my knowledge.) The drawing is a rough draft and there are some changes in the keel over all shape from the drawing in my post #14.
    The keels LE and TE are at approximately 45deg. angles to the hull so the PMB and t/c are not a constant percentage from WL to WL of the keel. The Tip of the keel has no PMB shape to it as the mid body and root have to them.
    The shape on wooden stick is a NACA foil shape that I have abandoned. I am going for a NSS foil if I can get the width for fasteners in the aft sections. Still have the rudder TE to design. ???
    A TMB foil shape look like a Mahi Mhai tuna or dolphinfish to me, which flies in the face of what I thought a good foil shape for below the water line was a couple of months ago.
    jenardiman and all who have helped so far, Thanks for sharing your knowledge.
    John



    upload_2019-9-19_20-39-5.png
     
    Last edited: Sep 20, 2019
  2. Howlandwoodworks
    Joined: Sep 2018
    Posts: 55
    Likes: 12, Points: 18
    Location: Columbia MO

    Howlandwoodworks John Howland

    ^ The keel lines in the Body Plane in the post #16 was for a NACA foil that I have abandoned, I have drawn a new keel design in the keels Waterline drawing, so the two don't match up. I haven't done a Table of Offsets for the keel plan yet, so the drawing is flakey still.
     

  3. rnlock
    Joined: Aug 2016
    Posts: 72
    Likes: 4, Points: 8, Legacy Rep: 10
    Location: Massachusetts

    rnlock Junior Member

    I don't think conventional airfoil shapes are relevant here. The flow on this keel will be 3D. The flow on a wing or a narrow, deep fin keel will be close to 2D over most of it.
     
Loading...
Similar Threads
  1. massandspace
    Replies:
    3
    Views:
    1,553
  2. 23feet
    Replies:
    31
    Views:
    7,658
  3. MichaelRoberts
    Replies:
    40
    Views:
    9,056
  4. laserek
    Replies:
    20
    Views:
    4,094
  5. quequen
    Replies:
    7
    Views:
    2,702
  6. waldemar123
    Replies:
    3
    Views:
    2,435
  7. KeithO
    Replies:
    6
    Views:
    474
  8. Wally2
    Replies:
    3
    Views:
    681
  9. Janne Enlund
    Replies:
    41
    Views:
    3,776
  10. surfbus
    Replies:
    44
    Views:
    7,248
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.