Comparative Study of Different Reduced Order Methods for Fluid-Structure Interaction and Validation With Experimental Results for a LNG Carrier

Ships and offshore structures are constantly exposed to wave loads during their lifetime. The detailed knowledge of their hydrodynamic properties is necessary to ensure the safety of the crew, structure and loading during operation. Therefore, wave loads are crucial to consider in the structural and seakeeping analysis of marine structures during their design process. The assessment of the hydrodynamic behaviour is obtained by numerical simulations accompanied by model tests for validation purposes. Reduced-order methods based on potential flow theory are mostly applied due to its computational efficiency. The aim of this study is to provide an overview on different established reduced order models discussing the theoretical foundation as well as limitations and applications. For this purpose, the sea-keeping behaviour of a LNG carrier is adressed as an application example in this study. The response amplitude operator (RAO) of the LNG carrier is determined with three different established numerical programs and validated by experimental results.