maxsurf motions help

Hi everyone,

I am new to this forum and to Maxsurf Motions. I am a Naval Architecture student, currently reading the manual while trying to apply what I learn to a design I created myself.

I am stuck on interpreting the results of the strip theory. The manual states:

"The first row, labeled Wave spectrum, has been obtained by integrating the wave spectrum as viewed by a stationary observer; the second (Encountered wave spectrum) from integrating the waves as experienced by the moving vessel. Both should give the same answer."

However, when I run the analysis, my results for 180º waves give me different values for the modal, mean, and zero-crossing periods. I tried following the manual's recommendation to fix this (increasing the frequency range), but it doesn’t seem to work.

Does anyone know what might be happening?