A new model was established to calculate the real vapor pressure of the Al element in the molten Ti x Al ( x = 25 ~ 50, mole fraction, %) alloy. The effects of the holding time, chamber pressure, mole fraction of Al ...A new model was established to calculate the real vapor pressure of the Al element in the molten Ti x Al ( x = 25 ~ 50, mole fraction, %) alloy. The effects of the holding time, chamber pressure, mole fraction of Al and melting temperature on the real vapor pressure of Al element in the vacuum chamber were analyzed. Because of the impeding effect of the real vapor pressure on the evaporation loss rate, within a short time (less than 10?s), the real vapor pressure tends to a constant value. When the chamber pressure is less than the saturated vapor pressure of the Al component, the real vapor pressure of Al is equal to the chamber pressure. While when the chamber pressure is larger than the saturated vapor pressure, the real vapor pressure is equal to the saturated vapor pressure of the Al element of the same condition.展开更多
In this paper, the lubrication problem in nmmerical sindation of forming processes is considered.After enumerationg the difficulties encountered when trying to solve such a problem with the finite element method, a ...In this paper, the lubrication problem in nmmerical sindation of forming processes is considered.After enumerationg the difficulties encountered when trying to solve such a problem with the finite element method, a generalization of the formaulation of Liu[4-6] for the thin film hydrodynamic lubrication re- gime is presented. This method is then aplied to a strip rolling simulation,using the Arbitrary La- grangian eulerian (ALE) formalism.展开更多
A computational procedure is developed to solve the problems of coupled motion of a structure and a viscous incompressible fluid. In order to incorporate the effect of the moving surface of the structure as well as th...A computational procedure is developed to solve the problems of coupled motion of a structure and a viscous incompressible fluid. In order to incorporate the effect of the moving surface of the structure as well as the free surface motion, the arbitrary Lagrangian-Eulerian formulation is employed as the basis of the finite element spatial discretization. For numerical integration in time, the fraction,step method is used. This method is useful because one can use the same linear interpolation function for both velocity and pressure. The method is applied to the nonlinear interaction of a structure and a tuned liquid damper. All computations are performed with a personal computer.展开更多
文摘A new model was established to calculate the real vapor pressure of the Al element in the molten Ti x Al ( x = 25 ~ 50, mole fraction, %) alloy. The effects of the holding time, chamber pressure, mole fraction of Al and melting temperature on the real vapor pressure of Al element in the vacuum chamber were analyzed. Because of the impeding effect of the real vapor pressure on the evaporation loss rate, within a short time (less than 10?s), the real vapor pressure tends to a constant value. When the chamber pressure is less than the saturated vapor pressure of the Al component, the real vapor pressure of Al is equal to the chamber pressure. While when the chamber pressure is larger than the saturated vapor pressure, the real vapor pressure is equal to the saturated vapor pressure of the Al element of the same condition.
文摘In this paper, the lubrication problem in nmmerical sindation of forming processes is considered.After enumerationg the difficulties encountered when trying to solve such a problem with the finite element method, a generalization of the formaulation of Liu[4-6] for the thin film hydrodynamic lubrication re- gime is presented. This method is then aplied to a strip rolling simulation,using the Arbitrary La- grangian eulerian (ALE) formalism.
文摘A computational procedure is developed to solve the problems of coupled motion of a structure and a viscous incompressible fluid. In order to incorporate the effect of the moving surface of the structure as well as the free surface motion, the arbitrary Lagrangian-Eulerian formulation is employed as the basis of the finite element spatial discretization. For numerical integration in time, the fraction,step method is used. This method is useful because one can use the same linear interpolation function for both velocity and pressure. The method is applied to the nonlinear interaction of a structure and a tuned liquid damper. All computations are performed with a personal computer.