The work presented in this paper deals with the analysis of the roll motion of ships with free surface liquids on board. A mathematical model for the evaluation of the ship rolling motion is developed. It is based on the matching of the standard uncoupled roll motion equation with the Reynolds Averaged Navier-Stokes equations for the simulation of liquid sloshing inside the partially filled tank. Some discussions are reported on the problems which can arise when the above matching is performed. In order to validate numerical results, an experimental analysis is planned, considering the scale model of a fishing vessel equipped with a rectangular tank partially filled with water. The results obtained by the numerical runs and experimental tests are shown in Part 2 of the present work.
As concerns maritime transportation, one of the challenges of the near future is constituted by the improvement in RO-RO safety. This is indeed essential also for the survival of this ship concept. After the last accident, the sinking of Estonia. panels have been formed in the frame of SNAME (Hutchison, 1995) and IMO (lMO News, 1995) to study the problem. Several international and national projects which concern RO-RO safety are currently running (Svensen, 1995; Vassalos, 1995; Shimizu et al., 1995). Nobody has concluded that this ship concept has to be abandoned. Everybody agreed that water accumulation and motion on the garage deck playa relevant role, so that ad interim and long-term solutions have to be individualized and applied as new regulations. We can in particular quote the following: "Future research … analytical research to extend the earlier SNAME Ad Hoc RORO Safety Panel studies to include: a) vessel heave and roll motion; water sloshing on the RO-RO deck …" (Hutchison, 1995).
