摘要
为提高固定结合面的建模精度,建立了基于各向同性虚拟材料的固定结合面修正模型。根据弹性模量和切变模量的本质属性,对各向同性虚拟材料法中等效微凸体弹性模量和切变模量的求解原理进行了修正,并在此基础上通过加权方法推导了各向同性虚拟材料弹性模量和切变模量的表达式。利用修正后的各向同性虚拟材料模型和有限元软件对含有固定结合面的框形结构进行模态分析,得到框形结构的前6阶理论模态。将理论模态和实验模态进行比较,结果表明:理论模态与实验模态的前6阶振型一致,前6阶固有频率相对误差的绝对值在10%以内,验证了修正模型的有效性。
The fixed joint surface correction model based on isotropic virtual material was established to improve the modeling accuracy of fixed joint surface. According to the essential attributes of elastic modulus and shear modulus,the theory of solving equivalent asperity's elastic modulus and shear modulus in isotropic virtual material modeling method was corrected,and the expressions of elastic modulus and shear modulus of isotropic virtual material were derived using weighting method. The model analysis of box-shaped structure with fixed joint surface was carried out using the correct isotropic virtual material model and the finite element software,and the first six theoretical modals of box-shaped structure were obtained. The theoretical modal is compared with the experimental modal,and the result shows that their first six modal shapes are identical and the absolute value of the relative error of their first six nature frequencies is less than 10%,which verifies the effectiveness of the correction model.
引文
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