Effects of Cross Currents Induced by Lateral Water Introductions on Ship Operation on Inland Waterways

Cross currents induced by lateral water introductions possibly influence ship operation on inland waterways by calling forth transverse movements of a ship while passing the cross currents influenced zone. In order to provide operational traffic safety on inland waterways these transverse movements are to be restricted by developing a suitable introduction construction for the lateral water introductions. As a rule, there are to steps to do. In a first step, the dimensions of the introduction construction are to be estimated based on theoretical appoaches. In a second step, physical model tests are to be carried out in order to check and if necessary to guarantee the hydraulic effectiveness of the introduction construction. Exemplarily for a lateral water introduction of a Rainwater-Collection-System of the city of Bamberg, Germany into the Main-Danube-Canal the above mentioned general proceeding for developing a suitable introduction construction for lateral water introductions into inland waterways considering defined boundary conditions is explained in detail showing especially a state-of-the-art theoretical approach for estimating the dimensions of the introduction construction. In this case the physical model tests were carried out in model flume. Cross current velocities at the outlet of the introduction construction were measured and transverse movements of a ship passing the introduction construction were documented. The results of the application example showed that the dimensions of the introduction construction could be estimated as a base for the physical model tests sufficiently exact using a theoretical approach considering the defined boundary conditions. In the physical model tests the hydraulic effectiveness of the introduction construction could be guaranteed by using constructive measures like bended current deflection walls, bended submerged walls and sills as well as current reflection walls resulting in suitable introduction construction for the defined boundary conditions.