Analysis Of The Influence Of Ship Form Parameters On The Vulnerability Of Parametric Rolling

In recent years,many ships which meet the requirements of complete stability criterion have occurred accidents,which have attracted the attention of the International Maritime Organization(IMO).For this reason,IMO and other countries have been working on the formulation of the second generation complete stability criterion.Considering five failure modes,based on the parametric rolling,one of them,the vulnerability and the influence on ship design are studied.The main work is as follows:.Firstly,study the development of the draft of parameter rolling vulnerability including 6 parent ships for the four types as fishing administration vessels,fishing vessels,container ships and bulk carriers.A total of 216 new series ship types were obtained from the variation of the main parameters of ship form,which were used to calculate the vulnerability of ships,and the results were cross-validated with the results of the software of the domestic research institute.The reliability of the series ship form obtained by the ship form transformation is verified,and the consistency of the calculation results of the parametric rolling balance is verified.Secondly,based on the calculation results of series ship types,the ship type parameters(vertical line length,shape width,shape depth,vertical coordinates of floating center,square coefficient,waterline coefficient,bilge keel area)and load factors(draught,height of center of gravity)which affect the ship's rolling vulnerability were studied.An analysis of the consistency of the influence laws of the first and second layers of vulnerability was carried out.The sensitivity ranking of the first layer and the second layer of the ship type parameters and the influence factors of the load condition on the rolling vulnerability of the parameters is obtained.Finally,take the C11 container ship series as an example.The parametric rolling vulnerability criterion was calculated.According to the influence of ship type parameters on the parametric rolling vulnerability,some measures and suggestions can be put forward to improve the parametric rolling vulnerability.Such as,reduce the height of gravity center and increase the ship width.Bilge keel area can improve the ship's parametric rolling vulnerability.Changing the vertical coordinates of the floating center,waterline coefficient and square coefficient have little effect on the parametric rolling vulnerability.Based on the evaluation of parameter rolling vulnerability of series ship types,this paper further expounds the influence of ship type parameters on parameter rolling,and studies the measures to improve ship safety from the point of view of design.