Numerical simulation and measurements on reduced scale structures of floating production storage and offloading units

Protecting offshore structures against the effects of lightning strikes, sparks, and short circuits is a considerable challenge to designers and deployment engineers once the numerous exposed structures, pieces of equipment, and devices make the behavior of electromagnetic phenomena difficult to predict. Numerical simulations are important tools to predict such behavior. However, due to the uncertainties involved, they should be compared against laboratory results. This paper presents the results of the measurements performed on three scaled models and compares them to those obtained with two different applications, CST Studio Suite and NEC4. We elaborate hypotheses regarding the differences between laboratory results and those obtained using simulation software. As an application, after validating modeling techniques, the paper discusses the results of induction on cable loops on "gooseneck"chimneys commonly used in ships and floating production storage and offloading units.