针对某型号内燃机连杆的屈曲特性进行了有限元计算和分析。对于给定材料的连杆,分析了连杆基于欧拉临界载荷公式的特征值屈曲模态。在此基础上,对内燃机连杆进行了非线性屈曲研究。分析结果表明,连杆不会发生经典的欧拉屈曲现象,也就是...针对某型号内燃机连杆的屈曲特性进行了有限元计算和分析。对于给定材料的连杆,分析了连杆基于欧拉临界载荷公式的特征值屈曲模态。在此基础上,对内燃机连杆进行了非线性屈曲研究。分析结果表明,连杆不会发生经典的欧拉屈曲现象,也就是说在发生屈曲之前应该首先出现塑性屈服失效。引进连杆初始缺陷后,对应的作用在连杆上的最大载荷为75 k N,而在给定的工况条件下,作用在连杆上的最大实际载荷为35.6 k N。因此,连杆在实际工作中不会发生经典的屈曲失效,也不会发生塑性屈服,连杆工作状态安全可靠。展开更多
The tectonic stress patterns were determined by a fuzzy comprehensive assessment method. Data of in-situ survey and fault information were utilized in the method. First, by making pressure and tension in the direction...The tectonic stress patterns were determined by a fuzzy comprehensive assessment method. Data of in-situ survey and fault information were utilized in the method. First, by making pressure and tension in the directions of along-river, cross-river, shear clockwise, and shear counterclockwise , 26 types of tectonic stress patterns were presented. And the stress vector of each pattern was obtained with FE software by taking unit displacement as boundary load. Then, by taking the 26 types of tectonic stress patterns as index set and 3 main stresses as factor set and choosing various operators, comparison of directions of computational stress vector and survey stress vector was made and the most possible tectonic stress pattern was obtained. Taking the 26 types of tectonic stress patterns as index set and strike angle as factor set, comparison of relationships between formation of fault and tectonic stress was made,and the tectonic stress patterns were assessed with known fault information. By summarizing the above assessment results, the most impossible tectonic stress pattern was obtained . Finally an engineering case was quoted to validate that the method is more feasible and reliable than traditional empirical method.展开更多
文摘针对某型号内燃机连杆的屈曲特性进行了有限元计算和分析。对于给定材料的连杆,分析了连杆基于欧拉临界载荷公式的特征值屈曲模态。在此基础上,对内燃机连杆进行了非线性屈曲研究。分析结果表明,连杆不会发生经典的欧拉屈曲现象,也就是说在发生屈曲之前应该首先出现塑性屈服失效。引进连杆初始缺陷后,对应的作用在连杆上的最大载荷为75 k N,而在给定的工况条件下,作用在连杆上的最大实际载荷为35.6 k N。因此,连杆在实际工作中不会发生经典的屈曲失效,也不会发生塑性屈服,连杆工作状态安全可靠。
文摘The tectonic stress patterns were determined by a fuzzy comprehensive assessment method. Data of in-situ survey and fault information were utilized in the method. First, by making pressure and tension in the directions of along-river, cross-river, shear clockwise, and shear counterclockwise , 26 types of tectonic stress patterns were presented. And the stress vector of each pattern was obtained with FE software by taking unit displacement as boundary load. Then, by taking the 26 types of tectonic stress patterns as index set and 3 main stresses as factor set and choosing various operators, comparison of directions of computational stress vector and survey stress vector was made and the most possible tectonic stress pattern was obtained. Taking the 26 types of tectonic stress patterns as index set and strike angle as factor set, comparison of relationships between formation of fault and tectonic stress was made,and the tectonic stress patterns were assessed with known fault information. By summarizing the above assessment results, the most impossible tectonic stress pattern was obtained . Finally an engineering case was quoted to validate that the method is more feasible and reliable than traditional empirical method.
