LNG独立液舱裂纹扩展寿命评估效率改进方法研究  

Improving Efficiency of Crack Propagation Life Assessment for LNG Independent Tank

作　　者：孙强 李柏锐 潘帅 彭东升 郭强 陈景杰[2] 黄一[2] SUN Qiang;LI Bairui;PAN Shuai;PENG Dongsheng;GUO Qiang;CHEN Jingjie;HUANG Yi(Dalian Shipbuilding Industry Co.,Ltd.,Liaoning Dalian 116000,China;Dalian University of Technology,Liaoning Dalian 116000,China)

机构地区：[1]大连船舶重工集团有限公司,辽宁大连116000 [2]大连理工大学,辽宁大连116000

出　　处：《装备环境工程》2024年第11期110-117,共8页Equipment Environmental Engineering

摘　　要：目的 对考虑超低温液体存储环境因素影响的LNG独立液舱裂纹扩展寿命和泄漏量评估方法进行改进。方法 以LNG独立液舱易萌生裂纹损伤区域为研究对象,采用裂纹尖端应力强度因子经验公式和裂纹扩展速率公式,分析具有108次循环的疲劳载荷在不同的排序方式下对裂纹扩展寿命的影响,找出影响计算精度和效率的主要因素。结果 裂纹扩展程序计算效率低下及应用条件受限是因为载荷循环次数过于庞大,对此提出了2种简化的裂纹扩展模拟方法,使裂纹扩展程序循环次数降低了5个量级。结论 这2种方法不仅极大地提高了计算效率以及降低了程序的使用要求,而且均可以达到较高的计算精度,为LNG独立液舱裂纹扩展寿命评估程序推广应用奠定了基础。The work aims to improve the evaluation method of crack propagation life and leakage of LNG independent tanks considering the influence of ultra-low temperature liquid storage environments.Taking the crack propagation area of LNG independent tanks as the research object,the empirical formula of crack tip stress intensity factors and the crack propagation rate formula were used to analyze the effectof fatigue load with 108 cycles on crack growth life under different sequencing modes,and the main factors affecting the calculation accuracy and efficiency were found out.The calculation efficiency of the crack propagation program was low and the application condition was limited because the load cycle number was too large.In this paper,two simplified crack propagation simulation methods wereproposed,which couldreduce the cycle number of the crack propagation program by 5 orders of magnitude.These two methods not only greatly improve the calculation efficiency and re-duce the application requirements of the program,but also achieve high calculation accuracy,which lays a foundation for the popularization and application of the crack growth life evaluation program of LNG independent tanks.

关 键 词：LNG独立液舱 裂纹扩展 应力强度因子 疲劳载荷 计算效率 寿命评估 

分 类 号：U661.4[交通运输工程—船舶及航道工程]