含模糊变量的复杂结构随机有限元分析及其应用

将影响复杂机械结构特性的变量的随机性和模糊性相结合，用概率方法处理模糊变量，求得模糊变量的模糊概率密度，然后对结构进行随机有限元分析。以液压机框架为例对含模糊变量的复杂结构进行随机有限元分析，计算结果更能反映工作过程的实际情况，克服普通有限元分析的局限性，为结构可靠性和优化设计提供更可靠的信息。

PROBABILITY FINITE ELEMENT ANALYSIS METHOD AND APPLICATION FOR COMPLEX STRUCTURE WITH FUZZY VARIABLES

With the complexity of the structure of mechanical product,its static and dynamic property was influenced by more and more factors(or variables). Random and fuzziness of some variables are universal,and should be taken consideration as to make theory model accord with the fact. According to the fuzzy probability theory,the probability density distributing function of fuzzy variables of complex structure was obtained. Then,connected with other random variables,the statie fuzzy stress,fuzzy strain and mass of structure was calculated by probability finite element method(the dynamic parameters also can be got if needed). Use Hydraulic pressure machine as instance, the result values are very different from the values attained by traditional finite element method(FEM). It shown that for complicated structure, the result of static or dynamic property by traditional single FEM is not so reliable. Through this way,more reliable data can be obtained for structure reliability design.