三维裂纹板条动态断裂参量的线弹簧有限元法研究

【作者】 姜莹莹；

【导师】 柴国钟；

【作者基本信息】 浙江工业大学 ， 固体力学， 2003， 硕士

【摘要】 本文将线弹簧模型与有限元软件ANSYS相结合，对弹性表面裂纹的动态断裂参量进行了研究，所进行的工作主要有： 将传统的用于静态表面裂纹分析的线弹簧模型推广用于动态断裂分析，导出了相应的线弹簧本构关系，并与有限元(ANSYS)相结合，建立了相应的求解技术。 对含内埋椭圆裂纹的板条进行了静态和瞬态分析，得到的结果与已有的解吻合良好，对影响瞬态响应的因素如裂纹形状、裂纹深度、板条长度、板条厚度做了分析比较。 在ANSYS中提出了一种新的线弹簧单元用于表面裂纹分析，并分别用于表面裂纹静态与动态的分析，所得结果与已有解吻合良好，说明此单元模型的建立是成功的，最后对影响表面裂纹动态应力强度因子的因素做了分析。 本文所建立的三维裂纹动态断裂参量的分析方法，较之全三维有限元法大大简化了前处理过程和节省了计算机时。同时，保证了一定的分析精度。因此，作为一种工程数值分析方法，是非常适合的。更多还原

【Abstract】 This paper presents a method to calculate elastodynamic fracture parameters of surface crack by using the elastic line-spring model combined with perfect ANSYS software. The main content includes :The traditional line-spring model which is used in the static analysis of surface crack is extended to the dynamic case, the corresponding constitutive relations are derived and combined with the software ANSYS, and then the corresponding computational technique is formulated.A static and a transient analysis of an embedded crack in a long elastic strip are carried out. The results are approximate to the ones that existed. And the effects of the factors including the crack configuration, the crack depth, the strip length and the strip thickness on the transient response are discussed.A new line-spring element is established and combined into ANSYS ,which is used to analysis of surface crack . And static case and dynamic case are solved respectively, the results are consistent well with the accepted numerical solutions. It is shown that established element is successful , And the effects of the factors on the transient response are examined in detail.This method provided in this paper can simplify pre-process and drastically reduces computer time and achieve some certain accuracy as compared to full 3-D finite element method. It has shown that as an engineering numerical method ,it is suitable.更多还原