Please help me with my school project

Discussion in 'Props' started by deier, Apr 2, 2020.

Tags:
  1. deier
    Joined: Apr 2020
    Posts: 6
    Likes: 0, Points: 1
    Location: Romania

    deier Junior Member

    Hello guys, I am new here. I study Naval Architecture in my country and I need your help for a project. I never worked a project with a kaplan propeller, only B-waggeningen, but now I am required to for a tractor tug. I chose a propeller with a dwg (to see if it fits under) and i have a Dp=2106mm,T=263 Kn,n=273rpm,z=4 blades.Its fixed pitch propeller. There are 2 propellers.
    Now I need to find what engines do I need and other characteristics of the propeller like Ae/A0,P/D and so on.
    The tug needs to develop a 50Tbp bollard pull.
    Thanks!
     
  2. hoytedow
    Joined: Sep 2009
    Posts: 5,596
    Likes: 253, Points: 93, Legacy Rep: 2489
    Location: North of Cuba

    hoytedow Wood Butcher

    Tug skipper shared this info with me: Screenshot_20200402-220433~2.png
     
  3. hoytedow
    Joined: Sep 2009
    Posts: 5,596
    Likes: 253, Points: 93, Legacy Rep: 2489
    Location: North of Cuba

    hoytedow Wood Butcher

    More: Screenshot_20200402-221246~2.png
     
  4. hoytedow
    Joined: Sep 2009
    Posts: 5,596
    Likes: 253, Points: 93, Legacy Rep: 2489
    Location: North of Cuba

    hoytedow Wood Butcher

    He is known on this forum as Yobarnacle.
     
  5. hoytedow
    Joined: Sep 2009
    Posts: 5,596
    Likes: 253, Points: 93, Legacy Rep: 2489
    Location: North of Cuba

    hoytedow Wood Butcher

    From that info I gather each engine to be 2500 hp.
     

  6. johneck
    Joined: Nov 2011
    Posts: 242
    Likes: 12, Points: 18, Legacy Rep: 117
    Location: New England

    johneck Senior Member

    The rule of thumb about right, so you need approx 2500 HP/shaft to get to 50 MT; maybe a bit less with a Tractor tug. How did you arrive at 273 RPM? This is probably not very workable with that RPM/Diameter combination. The power is pretty high for that diameter, so to manage blade loading you are probably better off with a higher RPM.
     
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.