Methodology for Crack Growth Analysis in Ship Hull Structures Using Sea Wave Forecasting Models

Abstract

Naval structures, such as ships and other artifacts, have a limited life and begin to degrade as soon as they enter service due to fatigue and fracture processes. To manage this wear and tear, periodic inspections are performed to determine the need for corrective actions on cracked structures. Structural Health Monitoring (SHM) systems are designed to continuously measure or periodically monitor cracked components, helping to prevent catastrophic failures.

This paper presents a methodology to assess the integrity and prognosis of cracked structural components on ships through a combination of numerical computation, real-time data from SHM systems on crack size and satellite meteo-marine data. This methodology seeks to plan maintenance or repair operations in shipyards.

Marine loads on the ship's route are obtained using geolocation tools and satellite meteo-marine information systems. Using NOAA's WaveWatch III model for wave prediction and CFD numerical models for seakeeping analysis with future wave spectra, the future behavior of the ship is determined. The hydrodynamic loads and accelerations are transferred to a dynamic structural model based on the Finite Element Method to evaluate the structural response of the affected component. The state of stress and deformation in the crack zone is determined by the Finite Element Method.