In navigation areas with lateral restrictions, a ship's steering and manoeuvring behaviour is affected by hydrodynamic interaction between the ship and the boundaries of the waterways. Therefore, the realism of manoeuvring simulation runs, carried out for both waterways design and nautical training purposes, is determined by the availability of a mathematical manoeuvring model that includes a reliable representation of ship-bank interaction forces and moments.
From a practical point of view, the availability of a series of empirical expressions formulating the interaction forces as a function of the main ship characteristics and operational parameters would be very convenient. For this purpose, some institutions have carried out systematic model test series in order to develop a database on which a reliable mathematical model for shipbank interaction forces can be based. However, the number of parameters affecting the hydrodynamic forces is rather large: ship type and characteristics (L, B, T, CB, ...), bark configuration (slope, surface-piercing or flooded, ...), water depth, lateral ship-bank distance, ship speed, propeller rate, …
The formulations that have been proposed by some authors are therefore based on a rather limited number of model tests with a selection of ship models. As a consequence, the reliability of such expressions may be questioned if applied in conditions that are not covered by the experimental database.
The paper gives an overview of systematic model test series carried out in the Towing Tank for Manoeuvres in Shallow Water (co-operation Flanders Hydraulics - University of Ghent) in Antwerp (Belgium). Tests were executed with three ship models (a cape size bulk carrier, a panamax bulk carrier and a post-panamax container carrier) moving in parallel course along a vertical surface-piercing bank with varying water depth, lateral distance, forward speed and propeller rpm. The test results are compared with empirical formulae published in literature.
A regression formulation for the lateral force and yawing moment was developed for each ship model, as well as for other available test data from other institutes. The dependency of the regression coefficients on ship characteristics is discussed.