A Method For Numerical Simulation Of The Icebreaker In The Process Of Icebreaking

Since the impact between the icebreaker and sea ice is a complicated dynamical procedure,there is no mature and effective method to predict the interaction between them. Because of the development of the finite element technology and the material database, the dynamical simulation became an effective method for computing the interaction between icebreaker and sea ice. Constitutive model of sea ice is one of the key factors to decide the computing results when the nonlinear finite element method is applied. So the four constitutive models of sea ice were analyzed deeply. After the numerical computing results were compared to Lindqvist empirical formula result, the applicability of the four constitutive models was analyzed which had been used to numerical simulation. Based on the above results,a numerical method was proposed to predict the ability and structure strength of the icebreaker.The main work in this paper were(1) the parameters for the impact procedure were confirmed based on the comparison of the sea ice physical mechanical parameters with different loading rate.(2) After expounding the four constitutive models and their theories, the advantages and disadvantages were discussed.(3) The key technologies were summarized in the nonlinear finite element method and the relevant parameters were confirmed in numerical simulation. The second development of MSC.Dytran was done and the different failure criterions were realized successfully. A numerical computing method was proposed to predict the ability, bow local strength and midship overall longitudinal strength of the icebreaker.(4) The interaction progresses were simulated based on the continous breaking and crash breaking ways. The applicability of the four constitutive models was analyzed. The ability of breaking ice and structure strength of the icebreaker were computed.