HYDRODYNAMIC SHAPE OPTIMIZATION OF LARGE OFFSHORE STRUCTURES

The paper presents a hydrodynamic shape optimization procedure applica ble at an early design stage to develop offshore structures with impro ved seakeeping qualities. Nonlinear programming algorithms are used to find minima of the selected objective function which qualifies the de sign. Evaluation and comparison of different designs are based on sign ificant double amplitudes of forces and motions which are calculated f or a given design sea spectrum. The hydrodynamic analysis is combined with long term wave statistics to minimize expected downtime. Due to a powerful automated shape generation and discretization technique, the procedure allows us to optimize different types of offshore structure s. Results for various types of offshore structures are presented and verified by model tests. (C) 1997 Elsevier Science Limited.