Review of fluid mechanics problems on Ocean Thermal Energy Conversion (OTEC) pipeline systems

Ocean Thermal Energy Conversion (OTEC) offers a nearly limitless and sustainable energy solution for island and coastal regions reliant on imported fossil fuels. Despite these advantages, large-scale OTEC deployment remains limited by high capital investment, technological constraints, and significant engineering challenges. This paper provides an in-depth analysis of the dynamic behavior and engineering challenges associated with OTEC systems, emphasizing pipeline dynamics under internal and external flow conditions and their interactions with floating platforms. Critical aspects such as vortex-induced vibration (VIV), fluid–structure interaction (FSI), and the complexities of multi-pipeline configurations are explored. The review summarizes recent advances in theoretical modeling, numerical simulations, and experimental investigations, offering insights into pipeline dynamics, VIV phenomena, and FSI mechanisms. Key challenges identified include nonlinear coupling effects, platform-pipeline interactions, and the necessity for advanced modeling approaches. Future research is recommended to focus on the development of refined dynamic models, experimental validation methods, and pipeline design optimization to enhance structural stability. This study aims to provide a comprehensive foundation for the advancement and industrial application of OTEC technology, ensuring its sustainable and efficient operation in complex marine environments.