CALCULATION OF SHIP SINKAGE AND TRIM USING UNSTRUCTURED GRIDS

An unstructured grid-based, parallel free-surface flow solver has been extended to account for sinkage and trim effects in the calculation of steady ship waves. The overall scheme of the solver combines a finite-element, equal-order, projection- type three-dimensional incompressible flow solver with a finite element, two-dimensional advection equation solver for the free surface equation. The sinkage and trim, wave profiles, and wave drag computed using the present approach are in good agreement with experimental measurements for two hull forms at a wide range of Froude numbers. Numerical predictions indicate significant differences between the wave drag for a ship fixed in at-rest position and free to sink and trim, in agreement with experimental observations.

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