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In this research, experimental and numerical study was carried out for the current forces acting on a FPSO (Floating Production Storage and Offloading). First experiment was done in KRISO ocean engineering basin to measure current load and second test was carried out in the wind tunnel. 1/60 scale model was used for basin test and 1/230 scale model for wind tunnel test. In order to validate and compare CFD method, STAR-CCM+ was used. The coefficients of current load are compared. The pressure and vorticity are analyzed to investigate the current flow around FPSO. It is noted that the boundary conditions and characteristics of hydrodynamics must be considered for the analysis and CFD simulation. [ABSTRACT FROM AUTHOR]

This study investigated the effects of turbulent wind profiles, level of details of topside structures and operation modes of gantry cranes on wind loads of a FPSO vessel. In order to do the research objectives, we performed a series of wind tunnel tests for a FPSO vessel model with scale of 1/200. It was found from the tests that the wind loads measured at low detail model were mostly conservative results compared with those at high detail model. The measured wind loads at the NMD profile with exponent of 0.14 revealed roughly 19% greater than those at the Frøya profile in the entire range of wind directions. Slightly higher mean wind speeds of the NMD profile with exponent of 0.14 compared with the Frøya profile resulted in the increase of wind loads. The wind forces increased by up to 8.6% at operating mode compared with parking mode of crane. [ABSTRACT FROM AUTHOR]

The article discusses research which evaluated the design and performance of superstructure modification for air drag reduction of a container ship. Topics discussed include the preliminary analysis and configuration design, wind tunnel tests and comparison between wind tunnel tests and Reynolds Averaged Navier-Stokes (RANS) simulations.

The article discusses research which investigated the effect of wind on the zig-zag manoeuver of very large crude oil carrier (VLCC) in ballast condition. Topics discussed include descriptions of tank tests, wind tunnel tests and hydrodynamic derivatives at ballast condition and the coefficients of wind forces.

The article discusses research which developed a device for reduction of fluctuating lift on riser pipe. Topics discussed include a description of a technology of suppressing vortex induced vibration, computational fluid dynamics (CFD), tow tank test (TTT) and wind tunnel test (WTT) and riser pipe in unidirectional flow.

The article discusses research which examined the wind loads on a floating production storage and offloading (FPSO). Topics discussed include the principle of the FPSO model test including the wind profile simulation, coordinate system and data representation, comparison between experimental wind load and oil companies international marine forum (OCIMF) data.

The article discusses research which examined the snap roll hydrodynamics modelling for the submarine suitable to high incidence angle maneuver. Topics discussed include the coordinate system used in the study, dynamics modeling for submarine, the planar motion mechanism (PMM) test and hard turning simulation.

The effect of contour bumps on transonic drag reducing at off-design conditions of a supercritical airfoil have been examined in the paper. Research focuses on two-dimensional flow condition with Mach number of 0.78 and chord Reynolds number of 2.5 million. Different contour bump airfoil configurations are examined using numerical method. Recent tests on these models are conducted in 0.6m×0.6m transonic wind tunnel at CARDC to validate the drag reduction effect. The computational results indicate that a surface contour bump is capable of reducing transonic drag for moderate to high lift conditions, but raises the drag remarkably for lower lift condition due to the second shock wave generated near the aft of the bump. The experimental research shows a good agreement with the computational. With the computational and experimental evidences, the mechanism of contour bump's effect on transonic drag reduction has been further analyzed. [ABSTRACT FROM PUBLISHER]

The article focuses on a comparative study of the industry practice with computational fluid dynamics (CFD) and model test results on the hydrodynamic load prediction of a jack-up leg. The study showed that the approach of the Society of Naval Architects & Marine Engineers (SNAME) predicts conservative loads compared to the CFD and the model test results. The CFD showed more congruence to the wind tunnel test data and provides inputs on hydrodynamics and flow interference.

In order to change rudder angle of the models in the wind tunnel test, a rudder control system (RCS) based on CAN bus was designed. Through the rudder angle regulating by the feedback of Linearity variable differential transducer (LVDT), the RCS achieves high precision control. We present the makeup, principle, and design of hardware and software of RCS. According to the wind tunnel test, the RCS works well, the control precision achieves the design target as expect and the test data meet the needs. [ABSTRACT FROM PUBLISHER]

The article reports on a study concerning the wind tunnel test and computational fluid dynamic (CFD) simulation conducted on a steel modular tower and a multi-column tower for offshore wind turbines proposed by the Korean Research Institute of Industrial Science and Technology (RIST). Topics discussed include the features of the towers, the mean wind force and moment coefficient data derived from the CFD and wind tunnel tests and a comparison of the two towers' performance.