Predictions of wave induced ship motions and loads by large-scale model measurement at sea and numerical analysis

Abstract

In order to accurately predict wave induced motions and load responses of ships, a new experimental methodology is proposed. The new method includes conducting tests with large-scale models under natural environment conditions. The testing technique for large-scale model measurements proposed is quite applicable and general to a wide range of standard hydrodynamic experiments in naval architecture. For the needs of this study, a large-scale segmented self-propelled model was designed for investigating seakeeping performance and wave load behavior and for testing the systems, and relevant experiments were performed. A two-hour voyage trial of the large-scale model in order to perform a series of simulation exercises was carried out at Huludao harbor in October 2014. During the voyage, onboard systems, operated by the crew, were used to measure and record the sea waves and the model responses. The post-voyage analysis of the measurements, both of the sea waves and the model’s responses, was made to predict the ship’s motion and load responses of short-term at the corresponding sea state. Furthermore, the numerical analysis of the short-term prediction was made using an in-house code and the result was compared with the experiment data. The long-term extreme prediction of motions and loads was also carried out based on the numerical results of the short-term prediction.