ssc-367 - Ship Structure Committee

The characteristic wave heights of a spectrum are related to the
total energy in the spectrum. The energy is proportional to the area
under the +*a2 spectrum.
Ha:
Average Wave Height
The average or mean height of all of the waves is found by setting
n=l.
Ha= 2.51*(mO)%
H~: Significant Height
The significant height is the average height of the highest one-third
of all the waves, often denoted as H 1/3”
Hs = 4.00*(mO)*
H max:
Maximum Height
The maximum height is the 1-gest wave height expected
number of waves, (n on the order of 1000), or over a
period, (t on the order of hours).
among a large
long sampling
The maximum wave height is often taken to be the average of the
l/1000th highest waves.
H = 7.94*(m )% = 1.985*Hs
1/1000 o
Using the one-over-nth equation and neglecting the second term gives
the following equation.
or
H
1/n
= 2*[ln(n)]+*(mO)%
A-10