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Old 03-01-2012
BryceGTX BryceGTX is offline
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Quote:
Originally Posted by davidpm View Post
There is no danger of large continuous waves.
On occasion a single 1 foot roller comes in caused by the wake of of boat.

In this specific case would some extra weight in the rigging have the effect of damping the sloshing?
Adding mass at the top of the mast will never create more damping. Rather, it somewhat negates the existing damping because the inertia is higher hence the frequency is lower.

That being said, since the natural frequency is lower, you may find the frequency of the waves do not align with the natural frequency of the boat so you can actually get a cancellation.

The more fundamental problem is that the natural frequency changes as the square root of the reciprocal of the inertia. So you need to add a bunch of inertia to have a significant effect on the natural frequency.

No doubt the big benefit to adding inertia is the reduction in frequency with the associated reduction in acceleration.

Quote:
Originally Posted by davidpm View Post
However if you hoisted say 50 lbs to the middle of the mast and only in quiet water to reduce rocking due to boat wakes
A more effective way to reduce the rocking is to add damping. AS you pointed out in a following post.. "rocker stoppers". These increase damping which gets right to the heart of the problem.

I think Bene505 was trying to create a similar effect with the anchors and lines. This could also increase the damping and inertia and righting moment. Incidently, the arm to calculate the inertia and righting moment would be half the beam.

Quote:
Originally Posted by Bene505 View Post
Great posts Bryce. Really brilliant.
Thanks for the compliment Brad..

Bryce

Last edited by BryceGTX; 03-01-2012 at 11:22 PM.
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