Please help me with my school project

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

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  1. deier
    Joined: Apr 2020
    Posts: 6
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    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
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    hoytedow Carbon Based Life Form

    Tug skipper shared this info with me: Screenshot_20200402-220433~2.png
     
  3. hoytedow
    Joined: Sep 2009
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    hoytedow Carbon Based Life Form

    More: Screenshot_20200402-221246~2.png
     
  4. hoytedow
    Joined: Sep 2009
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    hoytedow Carbon Based Life Form

    He is known on this forum as Yobarnacle.
     
  5. hoytedow
    Joined: Sep 2009
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    hoytedow Carbon Based Life Form

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

  6. johneck
    Joined: Nov 2011
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    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.
     
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