A perfect fit with results of diffraction calculations
was found.
In the classic strip-theory with the relative
motion approach, the amplification of the
incoming waves, due to waves produced
by the oscillating ship, has not been
accounted for. Based on the radiated wave
energy approach, a very simple method is
given here to calculate this amplification,
often referred to as dynamic swell-up.
Vertical relative motions in regular head
waves, measured at the bow of a model of
a cargo ship with forward ship speed, are
compared with calculated data. A fair
agreement was found.