A computer simulation model for thermal forming of ship and offshore structures

This paper presents a study on the line heating simulation process with an efficient “finite element analysis (FEA)” simulation model. The simulation model is conceived using concepts from three dimensional (3D) FEA of heat and mass transfer, plate theory and geometry, and implemented with commercially available software (Ansys*TM Mechanical APDL). The source of thermal energy is assumed to be “Gaussian” distributed heat flux, and we consider the temperature dependency of the material properties. The computer simulation model (CSM) is validated using the published experimental results. We study the discretization requirements for thick plates (>14 mm) that are commonly used in the shipbuilding processes and suggest guidelines for referential use in the industry. Also, we investigate the minimum time step size requirement during the cooling phase of the simulation process and based on the experimental numerical simulations, few efficient simulation practices have been coined, and we show that if they are followed then a noticeable gain in reduction of computational cost and time can be attained. We report extensive simulations of the estimated lines and then compare them with the target shape, and show a close agreement. Finally, our presented results are utilized to derive techniques for the improvement in existing FEA simulation models, and we show that the presented CSM is efficient for the application in ships and offshore structures for high bending of thick plates.