Study On Large Ship Hydroelastic Wave Loads Model Test

Hydroelastic wave loads prediction method considers the elastic deformation of ship structure as the response under wave excitation.Compared with the rigid theoretical wave load forecasting method,the hydroelastic wave loads prediction method which including the elastic effect of ship structure has more theoretical accuracy.To verify and analyze the influence of structural deformation to wave load on the ship,it is necessary to carry out the model test correctly.Firstly,by analyzing the principles and basic requirements of ship wave loads hydroelastic model test,determining the correct model design and assembly methods,and analyzing the uncertainties in model test,this thesis determines the experimental method of ship wave loads hydroelastic model test systematically.Secondly,based on the linear system motion equations,this thesis carried out a detailed analysis of linear elastic deformation of the ship hull considering the hydroelastic theory and its impact to the ship hull loads,and analyzing the linear elastic vibration phenomenon in ship wave loads hydroelastic effect,according to the linear vibration theory.As a supplement,a briefly description of the system response characteristics under the nonlinear structure assumption was introduced,which providing a theoretical basis for the subsequent result analysis of model test results.Finally,based on 550,000 tons ore carriers,two samples of lower stiffness ships were virtually designed,and model test was performed based on the certain ship wave loads hydroelastic prediction method.By comparing the seakeeping capacity of the two samples based on the different wave load forecasting methods with model test results to analyze the influence of structural elastic effect to ship motion and wave loads;and verify the calculation accuracy of linear water elastic theory.Spectral analysis and filtering of the test measurements were carried out to obtain the response components of different frequency,and analyzing the nonlinear response characteristics of the ship structure in details.