Join Date: Nov 2007
Location: SF Bay area
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Re: Why is beam reach (or near to it) the fastest point of sail?
I understand that it is possible to drop more pressure across the sail surface by accelerating the airflow across the leeward side
That's what I had always understood as well. However, do you know about Arvel Gentry's ideas? He says that the slot effect actually decelerates airflow on the forward lee side of the main, and that this reduces the pressure gradient and thereby reduces separation of flow.
He bases this on actually measuring flow rather than the guessing that he accuses previous researchers of doing. Hm!
See Magazine Articles
, especially "Another look at the slot effect".
s/v Laelia - 1978 Pearson 365 ketch
s/v Essorant - 1972 Catalina 27