• Journal of Ocean Engineering and Technology
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• v.16 no.5
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• pp.41-48
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• 2002

Numerical experiments are conducted using a three-dimensional baroclinic equation model and a Lagrangian method for clarifying the effect of th settling velocity on the suspended solids diffusion caused by the dredging and the reclamination works. Diffusion characteristics of the neutral particles and the weighting particles is experimented by the Lagrangian particles trajectory model, The results show that the diffusion characteristics of the suspended solids is effected by the settling velocity classified by the particles size in the density layered semi-closed bay. To estimate exactly the diffusion characteristics of the suspended solids and the contaminant with weight the three-dimensional baroclinic equation model and the three-dimensional Lagrangian particles trajectory model considering the settling velocity of the particle in the density layered semi-closed bay must be used.

• Journal of Ocean Engineering and Technology
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• v.15 no.4
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• pp.34-45
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• 2001

In the persent study, we conducted numerical experiments using a three-dimensional baroclinic equation model and a Lagrangian method for clarifying the hydrodynamics in Osaka Bay under the yearly mean discharge and visualizing the behaviour of particles of different settling velocity discharged from Yodo River and sedimentation pattern on the sea bottom. Particles are transported from the Yodo River to the south direction by the residual circulation of the bay head at the first stage, and after most of suspended solids particles are settled down at any layer and returned in the south-east coastal area through bottom layers by an estuarine circulation. The results show that estuarine circulation plays an important part of suspended solids transportation in the Osaka Bay.

• 한국해양학회지
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• v.28 no.2
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• pp.86-100
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• 1993

Three-dimensional baroclinic hydrodynamic model, BACHOM-3, is developed using ADI finite difference scheme. The model is applied to a uni-nodal standing wave in a rectagular basin. The model results for the surface elevation and velocities coincide with the analytical results. To verify the field applicability of the model and to investigate the flow patterns of the Suyoung Bay in Pusan, Korea, the model is applied to the bay. The numerically predicted velocity predicted velocity fields during spring tide at normal river flow are compared with field measurements, the comparisons show good agreement. A clockwise residual circulations at the first level (depth = 0∼2m) and the second level (depth=2∼5 m) of the central part of the bay occur, and the ebb flow is stronger than the flood flow. Computed velocity fields show that the phase difference of velocities between the surface layer and bottom layer occurs and the phase lag increases with height from the bottom. Then, the model is applied successfully for the computation of flow fields considering flood river flow and wind effects. When the wind is blowing toward the land from the sea, the flow patterns at the surface layer correspond with the wind direction, but the flow patterns at the near solid boundary of the lower layer show opposite currents to the wind direction.