1 Propeller induced loads on quay walls Maria Bauer, Moustafa Abdel-Maksoud Abstract: Ports have an important environmental and economical relevance due to their role as interface between the maritime traffic and land transport. In the future, cargo handling in ports will rise and ship dimensions will increase. Manoeuvrability of huge ships in narrow waterways causes new challanges on harbour facilities. In the present article the focus lies on the calculation and analysis of propeller induced loads on quay walls and harbor bed in ports. We first model the flow around propellers by means of potential theory and use an inhouse simulation tool for the computation of operational loads induced by propeller slipstream. The simulation tool introduced here is a three-dimensional first-order panel method which is constantly enhanced and can be used for various flow problems. In a second stage we show an application case and investigate the ability of our panel method to simulate the start up process of a ship where the propeller induces a slipstream close to port facilities. In addition, suggestions for possible extensions of the simulation tool, e.g. related to cavitation modeling and consideration of a free surface are outlined. 1 Introduction Due to increasing container ship dimensions the challanges on ports for container ships will rise. Manoeuvrability of such ship giants in narrow waterways turns out to be difficult. During the ship maneuvering process the ship propeller induces a flow. This flow affects the harbor bed and quay walls in the harbor. The docking pressure on quay walls caused by propeller slipstream of huge ships is far higher than by smaller units. For a better understanding of such complex interactions between ship and port facilities and for the prediction of operational loads induced by propeller flows there is a need in adequate computational simulation tools. For the investigation of propeller induced loads on port facilities, a three-dimensional panel method is used in this work. Panel methods are based on potential theory, where the flow is assumed to be incompressible, irrotational and inviscid. Methods based on the potential theory are widely spread in propeller design due to their short calculation time. Thus, the usage of a potential based boundary element method allows variation of the geometrical parameters within a wider range compared to other methods, such as RANSE or other field methods as calculation time is much shorter and the generation of grids is not as sensitive to distorted geometries. In the present study an existing inhouse simulation code ISThydro is used in order to estimate propeller induced pressure fluctuations on quay walls and harbor bed due to propeller action