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In the present paper presented are the results of prediction of total resistance of inland waterway vessels based on model test data. In scaling the resistance from model to full scale the extrapolation with two-dimensional frictional resistance formulation (without form factor) was applied, combined with different methods of determination of frictional (viscous) resistance coefficient. There were used the equations that include the effect of water depth, with and without account for pressure gradient. It was shown that limited depth of water substantially affects the frictional resistance. The results of example calculations are compared to resistance prediction made using the ITTC 1957 model-ship correlation line. Example calculations take into account the limited depth of water. Depending on the applied method of determination of frictional resistance coefficient the resultant total resistance of inland waterway vessel is higher or lower than the resistance based on the ITTC 1957 correlation line. The effect of water depth depends on the ratio of water depth to ship draught (h/T), on ship speed, and on the composition of a convoy. The extrapolation of resistance was made without including the form factor. Computations are made based on model test data for an inland waterway cargo vessel, for a kombi-type convoy of an inland waterway cargo vessel and a dumb barge, and for a convoy of two dumb barges without a pushboat.

By using fully theoretical method the heeling moment due to centrifugal forces has been determined for a small river cruiser in turning manoeuvre. The authors applied CFD software for determination of hull hydrodynamic forces, and open water characteristics of ducted propeller for estimation of thrust of rudder-propellers. Numerical integration of equations of 3DOF motion was used for prediction of ship trajectory and time histories of velocities, forces and heeling moment.

The paper presents an analysis of the impact of the physical phenomena occurring during the movement of a vessel in shallow water on the number of accidents on inland waterways. On the basis of data on the accidents on German waterways it has been established that the phenomenon of ship squatting significantly contributes to accidents connected with the suction of the vessel to the bottom of the waterway. Such failures are the cause of over 35% of all the accidents on inland waterways. Another factor increasing the probability of a failure is the negative impact of the waves produced by the movement of the vessel and of the screw race. The size of squatting and the intensity of the negative impact of the waves and the screw race depend on the sailing speed and the waterway restrictions. [ABSTRACT FROM AUTHOR]

The results of numerical computations of the flow around the hull of an inland vessel on a restricted waterway are presented. Resistances to motion and screw propeller operating parameters, with hull and restricted waterway interactions taken into account, can be numerically computed. The computations were carried out using own computer code HPSDK and commercial FLUENT software. The two computational systems are complementary and allow one to make full numerical propulsion predictions. Numerical computations performed by means of the two systems can complement or even replace model studies. The obtained computation results show good agreement with the results of model studies. [ABSTRACT FROM AUTHOR]