ssc-367 - Ship Structure Committee

where,
f is the circular frequency.
The conversion between period and radial frequency is more
complicated.
111 = 2T/T
S(f) = T2*S(T)
s(w) = T2*S(T) / (2Ir)
where,
T is the period.
When converting between period and frequency, the abscissa axis is
reversed. Zero period becomes infinite frequency, and infinite
period becomes zero frequency.
Wave spectrum equations may be used with any length units by
remembering that the spectrum ordinate is proportional to amplitude
squared or height squared.
—
‘(m)meter = (0.3048)2*S(~)feet
The mathematical formulation for the wave spectrum equation will
often include the significant height squared or the gravitational
constant squared, which when entered in the appropriate units will
convert the equation to the desired length units.
A.2 PROBABILITY CHARACTERISTICSOF WAVE SPECTRA
The characteristics of ocean waves are determined by assuming that
the randomness of the surface of the sea can be described by two
A-5