Propeller calculation

Discussion in 'Boat Design' started by Sarfaraz Manjra, Jan 28, 2019.

  1. Sarfaraz Manjra
    Joined: Jan 2019
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    Location: India

    Sarfaraz Manjra New Member

    Currently I am an intern working to a design an electric boat with a load of 350 KG . To select the right motor I needed calculations for the thrust and torque of prop. i have tried searching sites for formulae but couldn't understant. Please can someone tell me the exact way to approach for my problem .
     
  2. Pammie
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    Pammie Senior Member

  3. Sarfaraz Manjra
    Joined: Jan 2019
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    Location: India

    Sarfaraz Manjra New Member

  4. gonzo
    Joined: Aug 2002
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    gonzo Senior Member

    Before calculating a propeller, you need to calculate the resistance (drag) of the hull at the target speed.
     
  5. Squidly-Diddly
    Joined: Sep 2007
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    Squidly-Diddly Senior Member

    I gotta question:

    Say you have a 300hp motor, and need to power a 30ft typical deep V planing hull that will weigh 4 tons (or whatever is a pretty typical setup of motor and hull).

    Which would go fastest: inboard/outboard, outboard or inboard(traditional shaft)?

    And about how much diff between those motor setups?
     
  6. gonzo
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    gonzo Senior Member

    I would say that it would be an inboard or outboard with surface piercing propellers
     

  7. JSL
    Joined: Nov 2012
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    JSL Senior Member

    some particulars on your boat and the speed you want to achieve would help: Otherwise, we are all guessing
     
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