I'm sorry Thom I don't follow your thought about RMS. How would
geometric mean be related to the time and size of current flow? If the
tide took twice as long to rise and fall, the RMS would be the same but
the actual current would be smaller would it not?

Cheers


Thom Stewart wrote:

Nav,

Why wouldn't you use a RMS relationship if it close to a sine wave?

Ole Thom

Nav,

RMS would be .707 of the Sine wave (Or there abouts) The Tide cycle
being 12 hrs. If we round off .707 to 70% times 12 hrs we would get 8.4
hrs. this would represent the straight line, or Max flow time. The
curved section of the sine wave RMS wise would be 30%. Sense we are only
concerned with a 1/2 wave (Tide Run in one direction) it would Be 15% on
the top (Start of the run) and 15% on the end.
1.8 from slack, 8.4 max flow 1.8 to slack
12hrs total.

Over the years, I've found that this describes the tide flow damn close.
As I explained in a previous post, The slack is the problem. It can last
sometimes for over an hour and at time it doesn't even seem to exist but
the hour and 40minutes still holds up pretty well to max low.

So, as the tide runs start to slow down, you have about 1hr3/4 to make
your inlet on the slack.

As I said before; BE EARLY

Ole Thom