Multi-module floating body is an important structural type of offshore engineering equipment, which has attracted more and more attention from researchers in recent years. The evaluation of motion response, connector load, and overall structural strength is a key step in the design process of the multi-module floating structure. The traditional theory of rigid body motion cannot meet the requirements of performance evaluation of floating body with multiple modules, while the hydroelastic method can fully consider the effect of fluid-structure coupling and large deformation, and predict the performance of the structure more accurately. Therefore, in this paper, the hydroelastic theory will be adopted to analyze the performance of a multi-module floating body. In the process of finite element model analysis of the structure, the modal shape of the platform assumed as a flexible body was calculated, and the modal load of the connector and typical section of each module are acquired. Based on the modal shape obtained by the finite element method and the generalized fluid-structure coupling boundary conditions, the source strength is distributed on the wet surface element of the floating body, and the complicated Green Function is used to calculate the source strength and then the velocity potential and the hydroelastic response of the multi-module floating body. After obtaining the hydroelastic response of the floating body, the RAOs of the overall strength and the connector load of the structure are calculated by the mode superposition method. In this paper, the hydroelastic responses of the multi-module floating body under the working condition are illustrated, and also compared with the model test results. The short- and long-termed prediction of hydroelastic responses of the floating body under irregular waves is displayed, which plays important technical support for the design of the multi-module floating body.
Very large floating structures (VLFS) play an important role in the exploitation and utilization of marine resources. When the floating body reaches a certain scale, we often use the connecter to assemble multiple modules as a super large-scale floating platform. The fluid-structure coupling effect between multi-module VLFS and the surrounded waves will become very prominent. The traditional analysis method of taking the floating body as a rigid body is no longer suitable for the analysis of the performance of the floating body. The hydroelastic analysis method can fully consider the coupling effect of fluid and structure and acquire the coupling solution of fluid and structure, which can present the performance of multi-module VLFS more accurately.
