Application of computational fluid dynamics approach for modeling response of offshore pipeline and riser

Finite element (FE) modeling is commonly used in many civil engineering applications, especially in structural and geotechnical engineering. However, many geotechnical problems, such as large-scale landslides and debris flow and their impact on infrastructure cannot be modeled using typical FE programs developed in the Lagrangian framework because of numerical issues related to extreme mesh distortion. In recent years, large deformation finite element (LDFE) modeling techniques have been developed that can minimize/avoid mesh distortion issues to some extent. An alternative modeling technique is the computational fluid dynamics (CFD) approach, which shows some advantages over LDFE modeling for some applications, especially when the soil transforms into a fluid-like state due to remolding and fluidization. This paper presents some CFD simulation results with particular applications to offshore pipelines and risers.