This study reports the effect of vertical baffles on the group D powder mixing and drying characteristics in a batch fluidized bed dryer. Results obtained in this study showed that operating the fluidized bed dryer wi...This study reports the effect of vertical baffles on the group D powder mixing and drying characteristics in a batch fluidized bed dryer. Results obtained in this study showed that operating the fluidized bed dryer with vertical baffles gave better particle mixing. This is due to the fact that the vertical baffles acted to limit the growth of small bubbles into large bubbles and the small bubbles caused more vigorous mixing in the bed of particles before finally erupting at the bed surface. Thus, insertion of vertical baffles is a useful way to process group D particles in a fluidized bed, especially when the fluidized bed is large.展开更多
A finite difference model for solving Navier Stokes viscous liquid sloshing-wave interaction with baffles in a tank. equations with turbulence taken into accotmt is used to investigate The volume-of-fluid and virtual ...A finite difference model for solving Navier Stokes viscous liquid sloshing-wave interaction with baffles in a tank. equations with turbulence taken into accotmt is used to investigate The volume-of-fluid and virtual boundary force methods are employed to simulate free surface flow interaction with structures. A liquid sloshing experimental apparatus was established to evaluate the accuracy of the proposed model, as well as to study nonlinear sloshing in a prismatic tank with the baffles. Damping effects of sloshing in a rectangular tank with bottom-mounted vertical baffles and vertical baffles touching the free surface are studied numerically and experimentally. Good agreement is obtained between the present numerical results and experimental data. The numerical results match well with the current experimental data for strong nonlinear sloshing with large free surface slopes. The reduction in sloshing-wave elevation and impact pressure induced by the bottom-mounted vertical baffle and the vertical baffle touching the free surface is estimated by varying the external excitation frequency and the location and height of the vertical baffle under horizontal excitation.展开更多
t A series of inline pico hydropower systems,which could be used in confined space,especially for water distribution networks(WDNs),was designed and investigated.The turbine with an eye-shaped vertical water baffle wa...t A series of inline pico hydropower systems,which could be used in confined space,especially for water distribution networks(WDNs),was designed and investigated.The turbine with an eye-shaped vertical water baffle was developed to evaluate the hydraulic performance.A three-dimensional dynamic mesh was employed and the inlet velocity was considered as the inlet boundary condition,whereas the outlet boundary was set as the outflow.Then,numerical simulations were conducted and the standard k-εturbulence model was found to be the best capable of predicting flow features through the comparison with the experimental results.The effects of the opening diameter of the water baffle and installation angle of the rotor on the flow field in the turbine were investigated.The results suggested that the water baffle opening at d=30 mm and the rotor at a 52°angle could achieve the highest efficiency of 5.93%.The proper eye-shaped baffle not only accelerates the fluid flow and generates positive hydrodynamic torque,but also eliminates the flow separation.The scheme proposed in this paper can be exploited for practical applications in the water pipelines at various conditions and power requirements.展开更多
文摘This study reports the effect of vertical baffles on the group D powder mixing and drying characteristics in a batch fluidized bed dryer. Results obtained in this study showed that operating the fluidized bed dryer with vertical baffles gave better particle mixing. This is due to the fact that the vertical baffles acted to limit the growth of small bubbles into large bubbles and the small bubbles caused more vigorous mixing in the bed of particles before finally erupting at the bed surface. Thus, insertion of vertical baffles is a useful way to process group D particles in a fluidized bed, especially when the fluidized bed is large.
基金supported by the National Natural Science Foundation of China(Nos.51679079 and 51209080)the Fundamental Research Funds for the Central Universities(No.2014B17314)+3 种基金the Program for Excellent Innovative Talents of Hohai Universitythe Open Fund of State Key Laboratory of Hydraulic Engineering Simulation and Safety,Tianjin University(HESS-1703)the Open Fund Program of Key Laboratory of Water & Sediment Science and Water Hazard Prevention,Changsha University of Science & Technology(2015SS03)the 111 Project(B12032)
文摘A finite difference model for solving Navier Stokes viscous liquid sloshing-wave interaction with baffles in a tank. equations with turbulence taken into accotmt is used to investigate The volume-of-fluid and virtual boundary force methods are employed to simulate free surface flow interaction with structures. A liquid sloshing experimental apparatus was established to evaluate the accuracy of the proposed model, as well as to study nonlinear sloshing in a prismatic tank with the baffles. Damping effects of sloshing in a rectangular tank with bottom-mounted vertical baffles and vertical baffles touching the free surface are studied numerically and experimentally. Good agreement is obtained between the present numerical results and experimental data. The numerical results match well with the current experimental data for strong nonlinear sloshing with large free surface slopes. The reduction in sloshing-wave elevation and impact pressure induced by the bottom-mounted vertical baffle and the vertical baffle touching the free surface is estimated by varying the external excitation frequency and the location and height of the vertical baffle under horizontal excitation.
文摘t A series of inline pico hydropower systems,which could be used in confined space,especially for water distribution networks(WDNs),was designed and investigated.The turbine with an eye-shaped vertical water baffle was developed to evaluate the hydraulic performance.A three-dimensional dynamic mesh was employed and the inlet velocity was considered as the inlet boundary condition,whereas the outlet boundary was set as the outflow.Then,numerical simulations were conducted and the standard k-εturbulence model was found to be the best capable of predicting flow features through the comparison with the experimental results.The effects of the opening diameter of the water baffle and installation angle of the rotor on the flow field in the turbine were investigated.The results suggested that the water baffle opening at d=30 mm and the rotor at a 52°angle could achieve the highest efficiency of 5.93%.The proper eye-shaped baffle not only accelerates the fluid flow and generates positive hydrodynamic torque,but also eliminates the flow separation.The scheme proposed in this paper can be exploited for practical applications in the water pipelines at various conditions and power requirements.