How to cal. Estimated power at the propelleer

Discussion in 'Boat Design' started by Adeyele, Apr 15, 2013.

  1. Adeyele
    Joined: Jun 2012
    Posts: 48
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: Lagos

    Adeyele Junior Member

    Dear all,

    Can anyone help me on how to calculate this:

    A vsl is 30mtrs in lenght, with froude no of 1.49, wetted surf. Area is 160.54, spd 8kts, frictional rest. Is 67.8, Admiralty coefficient is 383.45. Using this fig. How can I estimate d engine power?

    Regards
    Mike
     
  2. gonzo
    Joined: Aug 2002
    Posts: 14,338
    Likes: 618, Points: 123, Legacy Rep: 2031
    Location: Milwaukee, WI

    gonzo Senior Member

    The power at the propeller is whatever you input on the shaft. The power the propeller can absorb you can get from the manufacturer's charts.
     
  3. jonr
    Joined: Sep 2008
    Posts: 721
    Likes: 11, Points: 0, Legacy Rep: 57
    Location: Great Lakes

    jonr Senior Member

    Maybe he meant "estimated power needed" to achieve the 8 knots. My guess - tow it and measure the force.
     
  4. Adeyele
    Joined: Jun 2012
    Posts: 48
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: Lagos

    Adeyele Junior Member

    Helo Gonzo,

    This is a calculation exercise so I wasn't given the details. All the figures are based on assumptions.

    Mike
     

  5. gonzo
    Joined: Aug 2002
    Posts: 14,338
    Likes: 618, Points: 123, Legacy Rep: 2031
    Location: Milwaukee, WI

    gonzo Senior Member

    Then you need to follow the rules and assumptions of the exercise. For example, do you use 90% of maximum power for calculations?
     
Loading...
Similar Threads
  1. mustafaumu sarac
    Replies:
    2
    Views:
    67
  2. thenavalarch
    Replies:
    0
    Views:
    116
  3. thenavalarch
    Replies:
    0
    Views:
    187
  4. thenavalarch
    Replies:
    3
    Views:
    246
  5. Len
    Replies:
    18
    Views:
    637
  6. somarine
    Replies:
    38
    Views:
    1,116
  7. Tasnel Tayyar
    Replies:
    22
    Views:
    749
  8. SBarlow
    Replies:
    10
    Views:
    459
  9. Bemboo
    Replies:
    14
    Views:
    406
  10. thenavalarch
    Replies:
    0
    Views:
    282
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.