A simulation of stratification and penetration was performed over a range of structural parameters that included screen width, aperture size, inclination angle, and wire diameter. The discrete element method （DEM） w...A simulation of stratification and penetration was performed over a range of structural parameters that included screen width, aperture size, inclination angle, and wire diameter. The discrete element method （DEM） was used for the simulations. The terms stratification and penetration are defined and the change in fine panicle concentration is discussed. Mathematical models relating fine particle ratio to time are established using the least squares method. The effect of structural parameters on fine panicle ratio is analyzed. Stratification and penetration rate are discussed by considering the time derivative of the fine panicle ratio. The conclusions are： an increase in inclination or wire diameter has a positive effect on par- ticle stratifying; The optimal screen width is 40 mm for panicle stratification; The inclination angle has a negative effect on the penetration; The effect of wire diameter and screen width on the penetration rate is negligible.展开更多
This article discusses computational methods for the numerical simulation of unsteady Bingham visco-plastic flow. These methods are based on time-discretization by operator-splitting and take advantage of a characteri...This article discusses computational methods for the numerical simulation of unsteady Bingham visco-plastic flow. These methods are based on time-discretization by operator-splitting and take advantage of a characterization of the solutions involving some kind of Lagrange multipliers. The full discretization is achieved by combining the above operator-splitting methods with finite element approximations, the advection being treated by a wave-like equation 'equivalent' formulation easier to implement than the method of characteristics or high order upwinding methods. The authors illustrate the methodology discussed in this article with the results of numerical experiments concerning the simulation of wall driven cavity Bingham flow in two dimensions.展开更多
基金the Special Topic Fund of Key Science and Technology of Fujian Province (No. 2006HZ0002-2) for the financial support
文摘A simulation of stratification and penetration was performed over a range of structural parameters that included screen width, aperture size, inclination angle, and wire diameter. The discrete element method （DEM） was used for the simulations. The terms stratification and penetration are defined and the change in fine panicle concentration is discussed. Mathematical models relating fine particle ratio to time are established using the least squares method. The effect of structural parameters on fine panicle ratio is analyzed. Stratification and penetration rate are discussed by considering the time derivative of the fine panicle ratio. The conclusions are： an increase in inclination or wire diameter has a positive effect on par- ticle stratifying; The optimal screen width is 40 mm for panicle stratification; The inclination angle has a negative effect on the penetration; The effect of wire diameter and screen width on the penetration rate is negligible.
文摘This article discusses computational methods for the numerical simulation of unsteady Bingham visco-plastic flow. These methods are based on time-discretization by operator-splitting and take advantage of a characterization of the solutions involving some kind of Lagrange multipliers. The full discretization is achieved by combining the above operator-splitting methods with finite element approximations, the advection being treated by a wave-like equation 'equivalent' formulation easier to implement than the method of characteristics or high order upwinding methods. The authors illustrate the methodology discussed in this article with the results of numerical experiments concerning the simulation of wall driven cavity Bingham flow in two dimensions.
