Global loads on a large size surface effect ship

A large project by the name of MATSTRUTSES to define materials and to develop structural solutions for a large SES was started in April 1994 A part of this project is to define the globai loads on the vessel This has been done using model experiments in a towing tank and by computations using linear and non-linear computer programs The project is carried out in the scope of the Brite Euram II programme This paper gives an overview of the results of the global loads definition The experimental technique will be explained and the CFD programs used will be introduced The experimental programme consists of tests at zero speed both in the off and oncushion mode and at forward speeds up to 75 knots in the on-cushion mode Calculations have been carried out with a 3-D diffraction program for the zero speed off-cushion case and with a strip theory program for the on-cushion condition Some typical results of the measurements are shown and they are compared to the calculations it is shown that non-linearities play an important role in the off-cushion condition, the agreement between computations and experiments increases if this nonlinear behaviour is taken into account The conditions giving rise to the highest loads in the construction are indicated, this load level will be used to define design loads for the considered design.