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    Re: Barrels was DR thread from Nov-Dec '04
    From: Doug Royer
    Date: 2005 Jan 19, 10:00 -0800

    And more fun than a barrel full of monkeys equals?  ;-)
    I got a chuckle out of the above.
    I checked my copy of Dutton's 12th edition last night and in sec. 806 was a
    2 paragraph discription of this phenominon.
    My copy of Bowditch 1984 edition,chapter XXXII has a better
    explaination.This is known as the Ekman Spiral or Ekman Current as George
    pointed out.
    So,the phenomina is well documented in other pubs.
    As for Bill's question about turns and fuel consumption the easiest way for
    me to show how much fuel these larger,laden vessels consume would be to take
    a question out of the C.G. exam for 3rd mate,unlimited as an example.
    Q: The speed necessary for reaching a point at the designated time is 18.0
    kt.The pitch of the prop is 23.9 ft.How many rpm will the shaft have to turn
    with a - 2 % slip to reach the point in the given time?
    My calculated rpm = 77 rpm
    If the fuel consumption at the above shaft rpm is 215 barrels/day what will
    be the fuel consumption if the vessel's speed is reduced to 14.0 kt.?
    My calculated consumption = 102.3 BBLS/day
    The correct answer = 101 BBLS/day
    Close enough to pick the correct answer out of the supplied answers but my
    calculated rpm is apperantly high as shown by the 102.3 barrels instead of
    101 barrels.So,in real life, you can see that a fair amount of money would
    be lost if calculated incorrectly.

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