CAJ | 학술논문

为实现移动式低温LNG贮罐的优化设计与安全运行,以高真空多层绝热结构LNG贮罐为研究对象,在分析其结构与承载特点的基础上,针对实际使用中经历的启动、制动、颠簸等多种工况,采用有限元方法分析了该类贮罐总体及局部的应力强度分布.结果表明:多种工况下,内容器内壁靠近滑动端支承的部位应力强度均最高,特别是遭遇羁绊颠簸时,其最大应力强度达到323.5MPa,比静态操作提高了62.5%,因此在LNG贮罐内、外容器上设置合适厚度与间距的加强圈对降低局部应力强度很有必要.同时水平加速度在-0.5 g-1.0 g区间交变时的疲劳分析与评定表明,LNG贮罐当前结构满足疲劳强度的要求,但最大交变应力强度点均出现在靠近固定支承的加强圈的边缘,说明结构不连续等对贮罐膜应力状态的破坏是导致疲劳失效的主因,故移动式LNG贮罐应尽量采用圆滑过渡结构.
위실현이동식저온LNG저관적우화설계여안전운행,이고진공다층절열결구LNG저관위연구대상,재분석기결구여승재특점적기출상,침대실제사용중경력적계동、제동、전파등다충공황,채용유한원방법분석료해류저관총체급국부적응력강도분포.결과표명:다충공황하,내용기내벽고근활동단지승적부위응력강도균최고,특별시조우기반전파시,기최대응력강도체도323.5MPa,비정태조작제고료62.5%,인차재LNG저관내、외용기상설치합괄후도여간거적가강권대강저국부응력강도흔유필요.동시수평가속도재-0.5 g-1.0 g구간교변시적피로분석여평정표명,LNG저관당전결구만족피로강도적요구,단최대교변응력강도점균출현재고근고정지승적가강권적변연,설명결구불련속등대저관막응력상태적파배시도치피로실효적주인,고이동식LNG저관응진량채용원활과도결구.
In order to achieve the optimum design and safe operation, the mobile cryogenic LNG storage tank with high-vacuum muhilayer insulation was researched with the help of finite element method on the basis of analyzing the features of structure and load The distributions of its global and local stress intensity corresponding to the behaviours of startup, brake and bumpiness, etc were also obtained. The results show the inwall of inner vessel near lower sliding support is the place with the highest stress intensity under multiple conditions, especially under bumpiness, the maximum stress intensity is above 323.5 MPa and 62. 5% higher than under static condition, so the stiffening rings with proper thickness and spacing should be situated on the inner and outer vessel of LNG storage tank to decrease the local stress intensity. In addition, the fatigue analysis and assessment, which is done against the alternation of horizontal acceleration between-0.5 g and 1.0 g, show the present structure of mobile LNG storage tank meets the requirements of fatigue strength. Simultaneously it is also found that the maximum alternate stress intensity occurs at the edge of stiffening ring near fixed support, which indicates the destruction to membrane stress system due to structure discontinuation is the major cause of fatigue failure, thus the mobile cryogenic LNG storage tank with rounding off structure is recommended.