Representative volume element (RVE) method and asymptotic homogenization (AH) method are two widely used methods in predicting effective properties of pe- riodic materials. This paper develops a novel implementa- ...Representative volume element (RVE) method and asymptotic homogenization (AH) method are two widely used methods in predicting effective properties of pe- riodic materials. This paper develops a novel implementa- tion of the AH method, which has rigorous mathematical foundation of the AH method, and also simplicity as the RVE method. This implementation can be easily realized using commercial software as a black box, and can use all kinds of elements available in commercial software to model unit cells with rather complicated microstructures, so the model may remain a fairly small scale. Several examples were car- fled out to demonstrate the simplicity and effectiveness of the new implementation.展开更多
This paper studies optimal shape design of pressure vessel head subject to internal uniform pressure.The optimization aims at minimizing its maximum stress while the volume of the vessel head remains no less than the ...This paper studies optimal shape design of pressure vessel head subject to internal uniform pressure.The optimization aims at minimizing its maximum stress while the volume of the vessel head remains no less than the standard ellipsoidal head.Super-ellipse curve is selected to describe the middle surface shape of the vessel head because it represents a large family of curves with only two or three parameters and makes the design and manufacture easy.The performance of different elements and element sizes of FEM modeling is carefully studied in view of computational cost,accuracy and noises of von Mises stress.The response surface of the maximum stress vs.shape design parameters is approximated by a Kriging surrogate model with EI criterion for sampling adding,based on the parameter optimization which is carried out to search the optimal shape.Finally,it is shown by numerical comparison that the super-ellipsoidal head is better than the standard ellipsoidal head and the other vessel heads in the literature.展开更多
The first version of Acta Mechanica Sinica (AMS) was launched in June 1985 in Beijing, aimed at delivering the cutting-on-edge progress and achievement in Mechanics in China to the world, allowing world-round collea...The first version of Acta Mechanica Sinica (AMS) was launched in June 1985 in Beijing, aimed at delivering the cutting-on-edge progress and achievement in Mechanics in China to the world, allowing world-round colleagues to access the work of Chinese mechanician, and supplying an international forum in the field. Its appearance was a result of 5-year preparation after the consensus agreement by the Acta Mechanica Sinica Editorial Board (3rd), and was approved by the China Association for Science and Technology and supported by the Chinese Society of Theoretical and Applied Mechanics (CSTAM).展开更多
基金supported by the National Natural Science Foundation of China(91216201)
文摘Representative volume element (RVE) method and asymptotic homogenization (AH) method are two widely used methods in predicting effective properties of pe- riodic materials. This paper develops a novel implementa- tion of the AH method, which has rigorous mathematical foundation of the AH method, and also simplicity as the RVE method. This implementation can be easily realized using commercial software as a black box, and can use all kinds of elements available in commercial software to model unit cells with rather complicated microstructures, so the model may remain a fairly small scale. Several examples were car- fled out to demonstrate the simplicity and effectiveness of the new implementation.
基金Sponsored by the National Natural Science Foundation of China(Grant No.9121620111128205)+1 种基金the National Program on Key Basic Research Project(Grant No.2011CB610304)the Fundamental Research Funds for the Central Universities(Grant No.DUT 11 ZD(G)04)
文摘This paper studies optimal shape design of pressure vessel head subject to internal uniform pressure.The optimization aims at minimizing its maximum stress while the volume of the vessel head remains no less than the standard ellipsoidal head.Super-ellipse curve is selected to describe the middle surface shape of the vessel head because it represents a large family of curves with only two or three parameters and makes the design and manufacture easy.The performance of different elements and element sizes of FEM modeling is carefully studied in view of computational cost,accuracy and noises of von Mises stress.The response surface of the maximum stress vs.shape design parameters is approximated by a Kriging surrogate model with EI criterion for sampling adding,based on the parameter optimization which is carried out to search the optimal shape.Finally,it is shown by numerical comparison that the super-ellipsoidal head is better than the standard ellipsoidal head and the other vessel heads in the literature.
文摘The first version of Acta Mechanica Sinica (AMS) was launched in June 1985 in Beijing, aimed at delivering the cutting-on-edge progress and achievement in Mechanics in China to the world, allowing world-round colleagues to access the work of Chinese mechanician, and supplying an international forum in the field. Its appearance was a result of 5-year preparation after the consensus agreement by the Acta Mechanica Sinica Editorial Board (3rd), and was approved by the China Association for Science and Technology and supported by the Chinese Society of Theoretical and Applied Mechanics (CSTAM).