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Old 02-06-2014, 12:19   #46
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Re: How common do you think rogue waves are?

Statistically there is about a 1 in 300 chance of the next wave being twice the average size. Wave sizing theory is relatively simple. It's all about superposition. However in practice what you experience is a random, broadband base excitation.

I used to be a test driver and vehicle dynamics tuner in the automotive and motorsport industry. I would either tune a vehicle for performance or comfort. Because you're tuning for a random broadband input you can't tune virtually. You must tune the actual vehicle in real world conditions. Providing the basic design is ok. Weight distribution, stifness, damping, etc you are left with 4 parameters to play with. Displacement, velocity, acceleration and jerk. (Yes jerk which is the rate of change of acceleration)

The human body only likes certain ranges of each of these parameters. Step outside those and you get sick, lose spatial awareness and can exceed safety of life thresholds. While i don't tune our yacht to the same degree of precision i would a vehicle the principles are the same.

Back to the topic of rogue waves. We can't do much about them other than ensure our vessel has a safe and comfortable motion. This is achieved statically through good weight distribution and dynamically through good seamanship and sail handling. Both are an ongoing work in progress.
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Old 02-06-2014, 12:40   #47
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Re: How common do you think rogue waves are?

Quote:
Originally Posted by MarkJ View Post
Cynics get Dementia. Remember that!
What was that again...???
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