A frequency-domain hydroelastic analysis of a membrane-based offshore floating photovoltaic platform in regular waves

Abstract

This study presents an approach for analyzing the hydroelastic response of membrane-based floating photovoltaic (PV) platforms. The structural deformation of the platform's main components, including a floater and a membrane, is further described through a comprehensive set of in-plane and out-of-plane modes. This analysis employs potential flow theory and 3D hydroelasticity theory to evaluate the hydrodynamic loads. Additionally, the Morison equation is utilized to express the drag term associated with the floater's in-plane motion. Addressing the connection between the floater and the membrane is achieved through the Lagrange multiplier method. Ultimately, this study establishes a frequency-domain coupled dynamic equation for the platform. The response results provide modal amplitudes and displacement data for test points, revealing that under low-frequency conditions, the flexible floater and the membrane conform to wave profiles. As the frequency increases, the impact of the floater's stiffness becomes prominent, resulting in a substantial three-dimensional interaction effect. In addition, this study examines various structural parameters, specifically the membrane pretension, elastic modulus, and the bending stiffness of the floater, to illustrate their influence on the motion and deformation of the platform. This work contributes to a deeper comprehension of membrane-based floating PV systems and their practical applications.