Optimisation Methodology Applied to Ship Design

Optimization with mathematical algorithms can be very helpful to find the best solution (minimum weight, minimum cost, maximum inertia, …). Typically, finite element analysis (FEA) tools are used in ship structural assessment. But, to build a FEM model from a CAD one is not easy and needs a big amount of manual work. This paper presents an innovative optimization workflow by which the following steps are automatically carried out, without any manual intervention. First, from the 3D CAD model, an idealized CAD model is created by the idealization module to take into account the FEM needs. Then, the idealized CAD model is transferred to the FEM tool. After that, the FEM model is meshed, loaded and solved. The obtained results (stress, volume etc.) are transferred to the optimizer. The optimizer
evaluates the values of the objective function and the constraints previously defined and modify the design variables (plate thickness and the stiffener scantling) to create a new structural model. After several iterations, the optimum solution is evaluated.