A feasible method to improve the reliability and processing efficiency of large vibrating screen via the application of an elastic screen surface with multiple attached substructures (ESSMAS) was proposed. In the ES...A feasible method to improve the reliability and processing efficiency of large vibrating screen via the application of an elastic screen surface with multiple attached substructures (ESSMAS) was proposed. In the ESSMAS, every screen rod, with ends embedded into elastomer, is coupled to the main screen structure in a relatively flexible manner. The theoretical analysis was conducted, which consists of establishing dynamic model promoted from the fuzzy structure theory as well as calculating for the equivalent stiffness of each attached structure. According to the numerical simulation using the NEWMARK-fl integration method, this assembling pattern significantly leads to the screen surface/rod having larger vibration intensity than that of the corresponding position on screen structure, which specifically, with an averaged acceleration amplitude increasing ratio of 11.37% in theoretical analysis and 20.27% in experimental test. The experimental results, within a tolerant error, also confirm the established model and demonstrate the feasibility of ESSMAS.展开更多
The deformation behavior of dispersion strengthened copper alloy Cu-Al2O3 was studied by TEM. The results show that nano-scaled dispersed second phase not only increases dislocation density in matrix, but also has an ...The deformation behavior of dispersion strengthened copper alloy Cu-Al2O3 was studied by TEM. The results show that nano-scaled dispersed second phase not only increases dislocation density in matrix, but also has an important influence on the dislocation substructure. The presence of fine dispersed Al2 O3 particles results in a uniform and random dislocation distribution in matrix copper and causes the difficulty in formation of dislocation cell structure and the decrease in the amount of cell structure during deformation. Deformation gives rise to much more dislocations and dislocation cells form more difficultly and the decrease in the cell size with the increase of dispersion degree.展开更多
Preliminary structure of light rail vehicle (LRV) carbody made of steel was designed considering its usage, strength, manufacturing, etc. Based on the finite element analysis, the optimization of design parameters ass...Preliminary structure of light rail vehicle (LRV) carbody made of steel was designed considering its usage, strength, manufacturing, etc. Based on the finite element analysis, the optimization of design parameters associated with thickness of LRV carbody is carried out to increase the whole strength of the carbody and to reduce its mass. With the aids of the substructure technique and the modified technique with discrete variables in the optimization based on the finite element method, the consumed computing time is reduced dramatically. The optimized LRV carbody is re-analyzed by FEM to obtain its static strength and vibrating mode and is manufactured. The mass of the optimized carbody reduces about 1.3 kg, and the relative reduction ratio is about 10%. Then, the strength test of the real carbody under the static load is executed. It is shown by the numerical and test results that the design requirements of the LRV carbody are satisfying. The newly designed carbody is used in the LRV, which is the first one used commercially developed by China independently. Nowadays, the LRV is running on the transportation circuit in Changchun of China.展开更多
基金Projects(50574091,50774084) supported by the National Natural Science Foundation of China
文摘A feasible method to improve the reliability and processing efficiency of large vibrating screen via the application of an elastic screen surface with multiple attached substructures (ESSMAS) was proposed. In the ESSMAS, every screen rod, with ends embedded into elastomer, is coupled to the main screen structure in a relatively flexible manner. The theoretical analysis was conducted, which consists of establishing dynamic model promoted from the fuzzy structure theory as well as calculating for the equivalent stiffness of each attached structure. According to the numerical simulation using the NEWMARK-fl integration method, this assembling pattern significantly leads to the screen surface/rod having larger vibration intensity than that of the corresponding position on screen structure, which specifically, with an averaged acceleration amplitude increasing ratio of 11.37% in theoretical analysis and 20.27% in experimental test. The experimental results, within a tolerant error, also confirm the established model and demonstrate the feasibility of ESSMAS.
文摘The deformation behavior of dispersion strengthened copper alloy Cu-Al2O3 was studied by TEM. The results show that nano-scaled dispersed second phase not only increases dislocation density in matrix, but also has an important influence on the dislocation substructure. The presence of fine dispersed Al2 O3 particles results in a uniform and random dislocation distribution in matrix copper and causes the difficulty in formation of dislocation cell structure and the decrease in the amount of cell structure during deformation. Deformation gives rise to much more dislocations and dislocation cells form more difficultly and the decrease in the cell size with the increase of dispersion degree.
文摘Preliminary structure of light rail vehicle (LRV) carbody made of steel was designed considering its usage, strength, manufacturing, etc. Based on the finite element analysis, the optimization of design parameters associated with thickness of LRV carbody is carried out to increase the whole strength of the carbody and to reduce its mass. With the aids of the substructure technique and the modified technique with discrete variables in the optimization based on the finite element method, the consumed computing time is reduced dramatically. The optimized LRV carbody is re-analyzed by FEM to obtain its static strength and vibrating mode and is manufactured. The mass of the optimized carbody reduces about 1.3 kg, and the relative reduction ratio is about 10%. Then, the strength test of the real carbody under the static load is executed. It is shown by the numerical and test results that the design requirements of the LRV carbody are satisfying. The newly designed carbody is used in the LRV, which is the first one used commercially developed by China independently. Nowadays, the LRV is running on the transportation circuit in Changchun of China.