Note on the intensity of encountered waves

Igor Rychlik, Sofia Åberg and Ross Leadbetter

Centre for Mathematical Sciences
Mathematical Statistics
Lund Institute of Technology,
Lund University,

ISSN 1403-9338
An apparent wave is a part of the sea record observed between two successive upcrossings of the still water level. Integral formulas are given for intensities of encountered waves that overtake a ship sailing in directional sea with constant velocity. The formulas can be evaluated exactly in the case when the directional spectrum is known and the sea is assumed to be Gaussian, i.e. is a sum of noninteracting sinusoidal waves.