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Profile for thorenj



Name thorenj
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  • 2013-03-13 12:06:30
    Re: Extrapolating boat performance
    Board » Technical Support
    I only have some limited experience working with polars, mainly from my bachelor's thesis in hydrodynamics, but i would suggest something along the lines of:

    BS(TWS)=BS(max polar TWS)+(TWS/(max polar TWS))x((max polar TWS)-(2nd max polar TWS))

    Hope I got that right... ;-)

    /thorenj

    --- Last Edited by thorenj at 2013-03-13 12:06:55 ---
  • 2013-03-10 13:24:42
    Re: Extrapolating boat performance
    Board » Technical Support
    Yes, obviously reefing will be important, but:

    a) As far as i know, reefing is already incorporated in the (nature of) polars, the boat speeds on beating wind angles seems to indicate this.

    b) The boat speed gets "stuck" to the maximum speed of the polar plot graph. Coincidence?

    Since we obviously can't have polars for infinite wind speeds, I believe that extrapolating the highest plotted wind speed will be the most accurate simulation. To improve realism, maybe the extrapolation could in fact be interpolation, but "above" the highest comparing value, to incorporate said reefing and wind angle-dependent factors.

    best regards,
    thorenj

    --- Last Edited by thorenj at 2013-03-10 13:31:57 ---
  • 2013-03-08 14:24:16
    Extrapolating boat performance
    Board » Technical Support
    Hi all - SOL developers in particular!

    As you may have noticed, in the current NYC-SFO race we have had stronger winds than those represented in the boat polar. When I took a closer look at what performance I got in winds of 40 knots or above, it seemed to me that the race server does not extrapolate boat speeds above what can be plotted in the graph in the client. Has anyone else experienced this? If this is an accurate observation, can it be rectified?

    best regards,
    thorenj

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