| Ships are subject to wave action when sailing in real marine environment,and the wave environment at sea has a great influence on the operational efficiency of ships.The increased resistance of ships sailing in waves will lead to extra fuel consumption and accompanying stall phenomenon,and the motion in waves also affects the safety and comfort of ships.The hydrodynamic performance of the drilling vessel needs to take into account the economy of sailing performance in multiple sea areas and working conditions and the operational requirements of long-time spot drilling and continuous core testing,which requires the drilling vessel to have the ability of rapid dispatch and long-time uninterrupted operation against waves.At present,the hydrodynamic performance evaluation system of the ship mainly focuses on the hydrostatic environment,and the influence of waves is seldom considered,and the evaluation system is mostly established by single performance such as rapidity and wave resistance,which has a great gap with the actual hydrodynamic performance of the ship.In this paper,a scientific and reasonable evaluation index system is established for the response value of drilling vessel in waves,and the fuzzy comprehensive evaluation method is used to make a comprehensive assessment of the hydrodynamic performance of the vessel in multiple sea areas and operating conditions.This paper analyzes the main operating sea areas and environmental conditions of drilling and mining vessels,determines the wave parameters under different working conditions,introduces the principles and methods for the construction of the hydrodynamic performance evaluation index system,conducts detailed research on the nature and characteristics of two primary performance indexes of ship’s rapidity and wave resistance in waves,and reasonably selects the characteristic parameters that have a greater influence on the ship’s hydrodynamic performance by analyzing several relevant characteristic parameters under each primary performance index.By analyzing a number of relevant characteristic parameters under each level of performance index,the characteristic parameters with greater influence on the hydrodynamic performance of the ship are reasonably selected as the secondary evaluation indexes,and a ship hydrodynamic performance evaluation index system is established.The response values of the rapidity index are calculated by using the CFD general analysis software STAR-CCM+,and the response values of the wave resistance index are calculated by using the3 D linear potential flow software COMPASS WALCS BASIC,and the response amplitude of each secondary evaluation index is calculated under different sea areas and different working conditions.The integrated hierarchical analysis(AHP)and entropy weighting method are used to assign weights to the indicators at all levels and construct a fuzzy comprehensive evaluation model.Based on the free deformation method(FFD)and CFD method,the optimization of drill ship profile was carried out with the objective of minimizing the total resistance,and the comprehensive performance score of the ship before and after optimization was calculated by the multi-level evaluation model based on fuzzy theory,and the influence of the change of wave parameters and ship type on the hydrodynamic performance was analyzed. |
