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This paper is devoted to the assessment of ship maneuvering simulation using different propeller models with the focus on a simplified propeller model that represents the action of the propeller by body force and uses propeller performance curve to determine propeller loading during ship maneuvering. Simulations are also performed with an actual propeller approach with which the propeller rotation is simulated directly with the Reynolds averaged Navier-Stokes equation (RANSE) solver. Both time accurate simulations using sliding grid and rotating frame approximations have been performed for comparison. The zigzag and turning circle maneuvers in calm water have been simulated for two different ship models, namely the ONR tumblehome (ONRT) test case and the KRISO (Korea Research Institute of Ship and Ocean) Container Ship (KCS) test case. Predicted ship motion is compared with measurement data to assess the accuracy of the numerical prediction using RANSE computations with different propeller models. [ABSTRACT FROM AUTHOR]

This article deals with the validation of the modelling and numerical simulation of a rowing stroke, by means of CFD. Simplified but realistic strokes were performed in a towing tank with a rotating arm and a real flexible oar. Those laboratory conditions are better controlled than those of in situ trials. An FSI procedure is developed to take into account the oar bending, which is essential in the physics of this flow. The results show that this numerical framework is able to reproduce qualitatively the real flow including the breaking of the free surface around the blade and the transport of the air cavity behind it. The profiles of forces are well reproduced, with propulsive forces overestimated by 5–12% for their maxima. The study also focuses on the computation of the uncertainties. It is highlighted that, even for this well-controlled experimental equipment, the uncertainties on the quantities of interest are of about 11%. In other words, the experimental uncertainty covers the numerical errors. So, this numerical modelling is validated and can be used for design and optimisation of blades and oars, or to contribute to the better understanding of the boat–oar–rower system and its dynamics. [ABSTRACT FROM AUTHOR]

A study is presented on ship-bank interaction effects in which viscous-flow solvers are used to predict the hydrodynamic forces and moments on the ship. The ship under consideration is the KRISO Very Large Crude Carrier (KVLCC2). For this hull form, Flanders Hydraulics Research (FHR) has conducted shallow water model tests in their towing tank equipped with surface-piercing banks and a vertical quay wall. The forces and moments on the KVLCC2 model were obtained for various water depths and lateral distances to the banks. Additionally, the wave elevation was measured between the quay wall and the ship model. In this study, two different CFD codes are used to predict the loads on the KVLCC2 as a function of the water depth and lateral position in the channel. The effect of propeller suction and free surface modelling on the results is quantified. Furthermore, comparisons will be made with CFD results from literature and potential flow computations to highlight the benefits of each approach. It will be shown that with careful setup of the computations, reliable predictions of the ship-bank interaction effects can be obtained. [ABSTRACT FROM AUTHOR]