LNG储罐地震响应分析方法比较研究

发布时间：2018-05-24 10:37

本文选题：LNG储罐 + 简化模型　；参考：《哈尔滨工程大学》2013年硕士论文

【摘要】：液化天然气(Liquefied Natural Gas,简称LNG)作为一种使用安全,热值高,洁净等诸多优势的能源,日益改变着我国能源结构的布局。面对高速的发展的LNG产业,大型LNG储罐的建造成本却居高不下,其原因在于缺少自主设计建造的技术。另一方面,LNG属于超低温、易燃、易爆物质,一旦发生泄漏,将产生严重的次生灾害,LNG储罐抗震性能就显得尤为重要。鉴于此,进行相关LNG储罐抗震性能的研究具有重要的意义。本文以存储量为16万立方米大型LNG储罐为例,采用相关储液罐地震响应分析理论对其内罐进行动液压力,底部剪力以及倾覆弯矩分析,并与有限元软件ABAQUS分析结果进行对比,评价LNG储罐的抗震性能。首先本文根据结构形式的不同,总结了对比了单容罐、双容罐、全容罐以及薄膜罐各自的特点,并对目前广泛采用的全容罐作了较详细的介绍,对建造LNG储罐的选择有借鉴意义。其次采用相关储液罐地震响应分析理论,从仅考虑地震作用下储液对罐壁的冲击作用,而忽略储液液面的晃动作用,和考虑储液随地面运动对罐壁的冲击作用、储液因罐壁变形与罐壁的耦联振动作用、储液面液体晃动两个方面对LNG储罐内罐进行地震响应分析,前者考虑储液罐壁面为刚性,后者考虑储液罐罐壁为柔性。将理论分析结果与钢制储罐抗震标准对比验证,可知刚性罐壁理论计算结果偏于危险,简化的Haroun-Housner方法与规范计算结果相近,罐壁底部应力在安全范围之内。然后采用有限元分析软件ABAQUS对LNG储罐进行地震时程分析,考虑到传统的数值模拟流固耦合作用计算效率很低,本文结合前述理论分析将地震作用下储液产生的动液压力等效为附加在壁面的质量,等效为惯性力作用,计算效率有很大提高。分别对LNG储罐内罐以及考虑混凝土外罐及保温层整体模型进行分析,可知LNG储罐外罐及保温层较好的限制了内罐的径向变形,在8度多遇地震作用下,储罐地震反应较小。
[Abstract]:As a kind of safe, high calorific and clean energy, LNG Natural Gas (lg) is changing the layout of energy structure of our country day by day. In the face of the rapid development of LNG industry, the construction cost of large LNG storage tanks remains high, which is due to the lack of independent design and construction technology. On the other hand, LNG belongs to ultra-low temperature, flammable and explosive materials. Once leakage occurs, serious secondary disasters will occur and the seismic performance of LNG storage tanks is particularly important. In view of this, it is of great significance to study the seismic behavior of LNG tanks. Taking the large LNG storage tank with a storage capacity of 160000 cubic meters as an example, the dynamic fluid pressure, bottom shear force and overturning bending moment of the inner tank are analyzed by using the seismic response analysis theory of the relevant liquid storage tank, and the results are compared with the results of the finite element software ABAQUS. The seismic performance of LNG storage tank is evaluated. Firstly, according to the different structural forms, this paper summarizes and compares the characteristics of single tank, double tank, full tank and thin film tank, and introduces in detail the full tank which is widely used at present. It can be used for reference in the construction of LNG storage tank. Secondly, based on the theory of seismic response analysis of liquid storage tank, considering the impact of storage fluid on tank wall only under seismic action, ignoring the sloshing of liquid storage surface, and considering the impact of storage fluid with ground motion on tank wall, Because of the deformation of the tank wall and the coupled vibration of the tank wall, the seismic response of the LNG tank is analyzed from two aspects of liquid sloshing on the storage surface. The former considers the wall rigidity of the storage tank and the latter considers the flexibility of the tank wall. By comparing the theoretical analysis results with the seismic standards of steel storage tanks, it can be seen that the theoretical calculation results of rigid tank walls tend to be dangerous, the simplified Haroun-Housner method is close to the calculated results of the code, and the stress at the bottom of the tank wall is within the safe range. Then the finite element analysis software ABAQUS is used to analyze the seismic time history of the LNG tank, considering the low efficiency of the traditional numerical simulation of fluid-solid coupling. In this paper, the dynamic hydraulic force produced by the liquid storage under seismic action is equivalent to the mass attached to the wall and the inertial force, and the calculation efficiency is greatly improved. By analyzing the internal tank of LNG tank and the integral model of considering concrete external tank and insulation layer, it can be seen that the external tank and insulation layer of LNG tank limit the radial deformation of the inner tank well, and the seismic response of the storage tank is small under the action of 8 degree earthquake.
【学位授予单位】：哈尔滨工程大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：TE972;TU311.3

【参考文献】