In the present study a Genetic Programing model (GP) proposed for the prediction of relative crest settlement of concrete faced rock fill dams. To this end information of 30 large dams constructed in seven countries a...In the present study a Genetic Programing model (GP) proposed for the prediction of relative crest settlement of concrete faced rock fill dams. To this end information of 30 large dams constructed in seven countries across the world is gathered with their reported settlements. The results showed that the GP model is able to estimate the dam settlement properly based on four properties, void ratio of dam’s body (e), height (H), vertical deformation modulus (Ev) and shape factor (Sc) of the dam. For verification of the model applicability, obtained results compared with other research methods such as Clements’s formula and the finite element model. The comparison showed that in all cases the GP model led to be more accurate than those of performed in literature. Also a proper compatibility between the GP model and the finite element model was perceived.展开更多
The paper puts forward a highly efficient and practical scan line based on the filling algorithm. The algorithm takes the lines of polygon as line segments with directions and introduces the concept of marked value wh...The paper puts forward a highly efficient and practical scan line based on the filling algorithm. The algorithm takes the lines of polygon as line segments with directions and introduces the concept of marked value when the apex of polygon faces scan line, determines whether there are intersection points between the lines of polygon and scan lines, by judging whether the marked value has changed or not. This method avoids the extra decision and treatment of odd points in traditional algorithm, and it needs little calculations but it is highly efficient.展开更多
By SIMPLE method and Van Leer scheme, a program on numerical simulation for 3D mold filling has been developed. The fluid flow field of gas and liquid is calculated in couples by a single phase N S equation using SI...By SIMPLE method and Van Leer scheme, a program on numerical simulation for 3D mold filling has been developed. The fluid flow field of gas and liquid is calculated in couples by a single phase N S equation using SIMPLE method, and free surface control equation is handled by Van Leer scheme. Then it is verified by an anti gravity mold filling of thin wall plate. In order to demonstrate its ability to simulate 3D casting, an anti gravity mould filling of a cube is computed by the program.展开更多
In the simulation of the metal injection moulding (MIM), the behaviours of feedstock are much di?erent from which of the polymer injection. It is a mixture of the metallic powder in high concentration and so...In the simulation of the metal injection moulding (MIM), the behaviours of feedstock are much di?erent from which of the polymer injection. It is a mixture of the metallic powder in high concentration and some plastic binder. The advance in simulation of the mould ?lling with such high viscous feedstock is featured by the development of a fully explicit vectorial algorithm. On the basis of previous explicit software realized by the authors, the new algorithm avoids the global solution for pressure ?elds and the use of MINI elements to improve its e?ciency. Except for the operations at element level, neither global solution nor the construction of global matrix is required in simulation. A special strategy is used to regulate the incompressibility condition in ?lled domain at each time step. In case of the MIM problems, this method provides a fast way to simulate the ?lling processes. The computational cost is about linearly proportional to the degree of freedom number. Moreover, this vectorial algorithm can be easily parallelized for high performance computation with multi-clusters. The comparison of numerical results with previous simulations on 3D cases proves the validity and e?ciency of new algorithm.展开更多
文摘In the present study a Genetic Programing model (GP) proposed for the prediction of relative crest settlement of concrete faced rock fill dams. To this end information of 30 large dams constructed in seven countries across the world is gathered with their reported settlements. The results showed that the GP model is able to estimate the dam settlement properly based on four properties, void ratio of dam’s body (e), height (H), vertical deformation modulus (Ev) and shape factor (Sc) of the dam. For verification of the model applicability, obtained results compared with other research methods such as Clements’s formula and the finite element model. The comparison showed that in all cases the GP model led to be more accurate than those of performed in literature. Also a proper compatibility between the GP model and the finite element model was perceived.
文摘The paper puts forward a highly efficient and practical scan line based on the filling algorithm. The algorithm takes the lines of polygon as line segments with directions and introduces the concept of marked value when the apex of polygon faces scan line, determines whether there are intersection points between the lines of polygon and scan lines, by judging whether the marked value has changed or not. This method avoids the extra decision and treatment of odd points in traditional algorithm, and it needs little calculations but it is highly efficient.
文摘By SIMPLE method and Van Leer scheme, a program on numerical simulation for 3D mold filling has been developed. The fluid flow field of gas and liquid is calculated in couples by a single phase N S equation using SIMPLE method, and free surface control equation is handled by Van Leer scheme. Then it is verified by an anti gravity mold filling of thin wall plate. In order to demonstrate its ability to simulate 3D casting, an anti gravity mould filling of a cube is computed by the program.
基金Project supported by the Research Fund for the Doctoral Program of Higher Education of China (No. 20020613005)and the French Programme of Alternant Doctoral Training.
文摘In the simulation of the metal injection moulding (MIM), the behaviours of feedstock are much di?erent from which of the polymer injection. It is a mixture of the metallic powder in high concentration and some plastic binder. The advance in simulation of the mould ?lling with such high viscous feedstock is featured by the development of a fully explicit vectorial algorithm. On the basis of previous explicit software realized by the authors, the new algorithm avoids the global solution for pressure ?elds and the use of MINI elements to improve its e?ciency. Except for the operations at element level, neither global solution nor the construction of global matrix is required in simulation. A special strategy is used to regulate the incompressibility condition in ?lled domain at each time step. In case of the MIM problems, this method provides a fast way to simulate the ?lling processes. The computational cost is about linearly proportional to the degree of freedom number. Moreover, this vectorial algorithm can be easily parallelized for high performance computation with multi-clusters. The comparison of numerical results with previous simulations on 3D cases proves the validity and e?ciency of new algorithm.