储油罐损伤检测的数值仿真  

Numerical Simulation of Oil Tank Damage Detection

作　　者：邵长金[1] 戴乐根 赵哲[1] 

机构地区：[1]中国石油大学(北京),北京102249

出　　处：《计算机仿真》2015年第11期411-414,共4页Computer Simulation

基　　金：中国石油大学(北京)基本科研基金资助(KYJJ2012-06-26)

摘　　要：研究储油罐的损伤检测问题,储油罐罐底的损伤一般用声发射的方法进行检测,技术较为成熟。储油罐罐壁的损伤可采用振动模态位移方法,然而由于储油罐罐壁本身具有一定的曲率,当发生微小损伤时,直接运用传统的振动模态位移曲率方法很难对损伤区域进行识别。为解决上述问题,提出根据二次模态曲率在损伤区域的变化来确定储油罐罐壁损伤的方法,将储油罐罐壁的模态位移进行差分处理得到模态曲率,再用五点中心差分求得二次模态曲率。采用有限元数值仿真对方法进行了验证,并与直接运用模态曲率的方法进行对比,结果表明,二次模态曲率值在损伤程度较小时,就会发生明显突变,利用二次模态曲率能够准确地识别储油罐罐壁一个或多个位置的损伤,为储油罐损伤准确检测提供了参考。The damage detection of oil tank is studied. The damage at the bottom of oil tank is detected by acoustic-emission techniques, which is a mature technique in oil tank damage detection. The damage of the sidewall can be detected by modal parameter. While the sidewall of oil tank is curved, it is difficult to detect the slight damage of the oil tank sidewall by traditional modal curvature method directly. Then a method of the oil tank damage identification is proposed, which is based on the value of secondary modal curvature changed obviously in the damaged area. And the secondary modal curvature is obtained by the five-point central difference of modal curvature. A finite element numerical simulation method is used to verify the identification of this method. And the simulation shows that, compared with the traditional modal curvature method, the secondary modal curvature change obviously in the damage area while the damage is slight. It is effective in detecting the damage of oil tank sidewall at one simple area or multiple locations by using the secondary modal curvature.

关 键 词：储油罐 二次模态曲率 损伤检测 

分 类 号：TP391.9[自动化与计算机技术—计算机应用技术] TE319[自动化与计算机技术—计算机科学与技术]