随着船舶向大型化发展势头迅猛,船舶碰撞所带来的灾难性后果也显著增大。为评估船舶结构的耐撞能力,国内外研究人员分别从试验和数值模拟2个方面开展研究工作。针对船舶碰撞场景的仿真模拟中,经常采用常应变失效准则来定义单元是否失效。然而失效应变取值强烈依赖于单元尺寸大小,因此,开展失效应变与单元网格尺寸关系研究对船舶结构的耐撞性能准确评估意义重大。本文通过对光板及加筋板的耐撞性能的试验研究,并应用非线性有限元软件LS-DYNA对试验结果进行仿真模拟,探讨了光板及加筋板的单元尺寸和失效应变之间的关系。结果表明:光板和加筋板的单元尺寸与失效应变关系曲线明显不同,因此采用常应变失效准则时应区别对待,不能混用。研究结论对船舶结构碰撞有限元仿真具有一定的指导意义。
With the development of ship towards to the large-scale, the results of accident due to ship collision are more seriously. In order to assess the crashworthiness of marine structures, the research work is conducted by numerical simulation and experiment. The constant strain failure criterion is used to simulate the ship collision occasion. It is important to study the relation between failure strain and element size for assessment crashworthiness of marine structures because of the failure strain strongly depending on the element size. In the present study, the results of lateral collision tests on unstiffened plate and stiffened plate are reported. The explicit finite element code LS-DYNA is used to simulate the tests. The result shows that there are great difference in failure strain verse element length between unstiffened plate and stiffened plate. Hence, these conclusions could support the future uses of failure strain for collision simulations.
2017,39(8): 59-63,84 收稿日期:2017-02-10
DOI:10.3404/j.issn.1672-7649.2017.08.013
分类号:U661.4
基金项目:国家自然科学基金资助项目(51579110)
作者简介:尤小健(1975-),男,硕士,高级工程师,研究方向为船舶总体设计
参考文献:
[1] International Maritime Organisation.Casualty statistics and investigations: Very serious and serious casualties for the year 2002.FSI.3/Cir.5, 2005; accessed on: 4 Aug 2008.
[2] KARLSSON ULF B, RINGSBERG JW, JOHNSON E, et al.2009 Experimental and numerical investigation of bulb impact with a ship side-shell structure, Marine Technology, 2009, 46(1), 16-26.
[3] CHO sang-Rai, LEE Hyun-seung.2009 Experimental and analytical investigations on the response of stiffened plates subjected to lateral collisions, Marine Structures, 22(1): 84-95.
[4] ALSOS HS, AMDAHL J.2009 On the resistance to penetration of stiffened plates, Part I-Experiments, International Journal of Impact Engineering, 36, 799-807.
[5] 庄科挺, 刘敬喜, 刘元丹, 等.船舶加筋板结构耐撞性能分析[J].中国舰船研究, 2011, 03: 16-20.
[6] 刘元丹, 刘敬喜, 肖曙明, 等.双壳船内壳和外壳结构耐撞性能的分析和比较[J].中国造船, 2012, 03: 121-128.
[7] 肖曙明, 刘敬喜, 王娜, 等.双壳船内外壳结构耐撞性试验与仿真研究[J].应用力学学报, 2013, 02: 257-261, 307.
[8] 刘敬喜, 崔濛, 龚榆峰.船舶碰撞仿真失效准则比较[J].中国舰船研究, 2015, 04: 79-85.
[9] 王自力, 顾永宁.船舶碰撞动力学过程的数值仿真研究[J].爆炸与冲击2001, 21(1): 29-34.
[10] 王自力, 顾永宁.超大型油轮双壳舷侧结构的碰撞性能研究[J].中国造船2002, 42(1): 58-63.
[11] KITAMURA O.2001 FEM approach to the simulation of collision and grounding damage, 2nd International Conference on Collision and Grounding of Ships, July, Copenhagen, Denmark.
[12] PAIK JK, PEDERSEN PT.1996 Modeling of the internal mechanics in ship collisions, 1996 Ocean Engineering, 23(2), 107-142.
[13] LEHMANN E, 2002 PESCHMANN J.Energy absobption by the steel structure of ships in the event of collisions, Marine Structures, 15, 429-441.
[14] WEVERS LJ, VREDEVEDT AW.1999 Full scale ship collision experiments.TNO-report 98-CMC-R0359, TNO, Delft.
[15] KORGESAAR M, EHLERS S.2010 An assessment procedure of the crashworthiness of an LNG tanker side structure, Ship Technology Research Schiffstechnik, 57(2), 108-119.
[16] ALSOS HS, AMDAHL J.2009 On the resistance to penetration of stiffened plates, Part Ⅱ-Numerical analysis, International Journal of Impact Engineering, 36, 875-887.