In the time domain analysis, the relative distances between the diffraction elements among the hydrodynamic interaction structures are checked. The error will be issued if the distance changes are large.
As shown below, please make sure the hinge connection points on the structures are at the middle of the gap. It may also improve if you could set the surfaces in the gap as non-diffraction surfaces.
Do you need to define some fenders in the gap to prevent the structures from collision?
You are navigating away from the AIS Discovery experience