The objective of this report is to investigate the possibility of determining open‐water propeller characteristics using Computational Fluid Dynamics (CFD). The propeller used in the current investigation is the four‐bladed propeller as used for the benchmark KRISO Very Large Crude Carrier 2 (KVLCC2) hull. The computed open‐water characteristics are not part of the CFD submission of Flanders Hydraulics Research (FHR) for Workshop on Verification and Validation of Ship Manoeuvring Simulation Methods (SIMMAN). Computations are executed according to the specifications of the International Towing Tank Conference (ITTC), where the angular velocity of the propeller remains constant and results are computed for a range of advance ratios ? by altering the forward velocity of the propeller. This contrasts with the recommendations of NUMECA for open‐water computations, where the forward velocity is held constant, and the advance ratio is changed by altering the angular velocity of the propeller. Computations are executed in a rotating frame of reference which allows for larger time steps than in a fixed frame of reference. The by NUMECA recommended time step values were however not strict enough for low values of the advance ratio: the smallest value used is 1/8 of the recommended value. A comparison between the numerical results and the reference values shows a good agreement. This type of computation could be used in the future as an alternative to experimentally determined open‐water propeller characteristics if a solution is found for the slow convergence at ? = 0.
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