Hazard Identification and Risk Management at the Tuban Oil and Gas Production Unit, Indonesia

Abstract

These Ro-Ro vessels are the backbone of inter–island transportation in Indonesia and require an efficient
propulsion system to reduce fuel consumption and improve maneuvering performance. This study investigates the influence
of ducted propellers on Ro-Ro vessels using Computational Fluid Dynamics (CFD) simulations. Four blades fixed pitch
propeller configuration with accelerating duct are examined with different radial gaps at the propeller tip to the inner duct
surface (0.1m, 0.3m and 0.5m) at rotational speed of 229 rpm and diameter of 4.202 m. the CFD model validation show
average deviation of 4.06 % for KT, 7.63 % for 10*KQ and 3.11 % for efficiency compared with the experimental data. It
indicated that the numerical approach is sufficiently reliable for further analysis. The open-water test results suggest that
adding a duct does not necessarily improve performance. At a 0.10m gap, thrust, torque, and efficiency decrease by 39.3%,
25.7%, and 20.3%, respectively, whereas the 0.5m gap still results in noticeable performance degradation. Wake-field
visualization indicates that smaller gaps produce stronger propeller–duct interaction, with more concentrated energy,
sharper velocity gradients, and greater instability near the duct outlet. These findings emphasize that duct geometry and tip
clearance must be carefully optimized for the vessel’s operating conditions to fully realize the energy benefits of a ducted
propeller system on Ro-Ro vessels.