“Calculate the wind load in the direction of the incoming wind from 0° to 180° with an angle of 30°

Discussion in 'Hydrodynamics and Aerodynamics' started by sun, Nov 3, 2021.

  1. sun
    Joined: Sep 2018
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    sun Senior Member

    When calculating the action of wind or waves in different directions on offshore structures, why only calculate the "0°~180° load in the direction of the incoming wind or waves"? Why are all "30° angles as an interval"?
     
  2. gonzo
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    gonzo Senior Member

    The maximum force is the only value of interest. That is what the design loads are.
     
  3. sun
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    sun Senior Member

    I want to calculate the force on a structure. How to choose wind direction or wave direction? (10°、20°、30°......360°)?
     
  4. CT 249
    Joined: Dec 2004
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    CT 249 Senior Member

    What force and why?

    As Gonzo implies, this is not a simple question.
     
  5. sun
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    sun Senior Member


    A new marine structure.
     
  6. gonzo
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    gonzo Senior Member

    Unless you are one of the sea gods, you don't get to choose the direction/force of the wind and waves. You need to use observed values for your location.
     
  7. TANSL
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    TANSL Senior Member

    As in many other calculations, it is difficult to know a priori which is the worst circumstance. One must calculate several options to know which is the worst condition among the several possible ones.
     
  8. wet feet
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    wet feet Senior Member

    Surely you ought to calculate the loads that may be imposed from any direction.Failing to include all scenarios would be negligent.
     
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  9. sun
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    sun Senior Member

    Thank you everyone for your valuable feedback.
     
  10. powerabout
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    powerabout Senior Member

    yes all the forces can be calculated, the offshore industry does it all the time.
    Sometimes from wind tunnel data if availible
    The Dynamic Positioning industry is required to do this on Dp vessels.
    You get printed tables from the DP supplier and the data is used in the DP software.
    You do front area and then beam area, wind calc at 10metre level std air density and then there are formulas to do the other angles.
     

  11. powerabout
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    powerabout Senior Member

    is common practice offshore and lots of companies do it
     
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