The present study is concerned with the computational fluid dynamics(CFD)simulation of turbulent dispersion of immiscible liquids,namely,water–silicone oil and water–benzene through Kenics static mixers using the Eu...The present study is concerned with the computational fluid dynamics(CFD)simulation of turbulent dispersion of immiscible liquids,namely,water–silicone oil and water–benzene through Kenics static mixers using the Eulerian–Eulerian and Eulerian–Lagrangian approaches of the ANSYS Fluent 16.0 software.To study the droplet size distribution(DSD),the Eulerian formulation incorporating a population balance model(PBM)was employed.For the Eulerian–Lagrangian approach,a discrete phase model(DPM)in conjunction with the Eulerian approach for continuous phase simulation was used to predict the residence time distribution(RTD)of droplets.In both approaches,a shear stress transport(SST)k-ωturbulence model was used.For validation purposes,the simulated results were compared with the experimental data and theoretical values for the Fanning friction factor,Sauter mean diameter and the mean residence time.The reliability of the computational model was further assessed by comparing the results with the available empirical correlations for Fanning friction factor and Sauter mean diameter.In addition,the influence of important geometrical and operational parameters,including the number of mixing elements and Weber number,was studied.It was found that the proposed models are capable of predicting the performance of the Kenics static mixer reasonably well.展开更多
Three-dimensional simulation of a multiphase flow is performed using the EulerianEulerian finite volume method in order to evaluate the separation efficiency and velocity field of deoiling hydrocyclones.The solution i...Three-dimensional simulation of a multiphase flow is performed using the EulerianEulerian finite volume method in order to evaluate the separation efficiency and velocity field of deoiling hydrocyclones.The solution is developed using a mass conservation-based algorithm（MCBA） with collocated grid arrangement.The mixture approach of the Reynolds stress model is also employed in order to capture features of turbulent multiphase swirling flow.The velocity field and separation efficiency of two different configurations of deoiling hydrocyclones are compared with available experimental data.The comparison shows that the separation efficiency can be predicted with high accuracy using computational fluid dynamics.The velocity fields are also in good agreement with available experimental velocity measurements.Special attention is drawn to swirl intensity in deoiling hydrocyclones and it is shown that the differences in velocity and volume fraction fields of different configurations are related to swirl distribution.展开更多
In this study computational fluid dynamics (CFD) approach was used to study mixing in an Industrial gold leaching tank. The objective was to analyze the extent of mixing in the tank by producing visual images of the v...In this study computational fluid dynamics (CFD) approach was used to study mixing in an Industrial gold leaching tank. The objective was to analyze the extent of mixing in the tank by producing visual images of the various mixing zones in the tank domain. Eddy viscosity plots that characterise the extent of mixing in the tank were generated in the flow field obtained by an Eulerian-Eulerian approach. The extent of mixing was found to be greatest in the circulation loops of the impeller discharge region and least at the top and bottom portions of the tank. Trailing vortices that contribute to some level of mixing were identified in between the impeller blades. This approach could be used to enhance optimum design of mixing vessels and to eliminate the need for pilot plants.展开更多
文摘The present study is concerned with the computational fluid dynamics(CFD)simulation of turbulent dispersion of immiscible liquids,namely,water–silicone oil and water–benzene through Kenics static mixers using the Eulerian–Eulerian and Eulerian–Lagrangian approaches of the ANSYS Fluent 16.0 software.To study the droplet size distribution(DSD),the Eulerian formulation incorporating a population balance model(PBM)was employed.For the Eulerian–Lagrangian approach,a discrete phase model(DPM)in conjunction with the Eulerian approach for continuous phase simulation was used to predict the residence time distribution(RTD)of droplets.In both approaches,a shear stress transport(SST)k-ωturbulence model was used.For validation purposes,the simulated results were compared with the experimental data and theoretical values for the Fanning friction factor,Sauter mean diameter and the mean residence time.The reliability of the computational model was further assessed by comparing the results with the available empirical correlations for Fanning friction factor and Sauter mean diameter.In addition,the influence of important geometrical and operational parameters,including the number of mixing elements and Weber number,was studied.It was found that the proposed models are capable of predicting the performance of the Kenics static mixer reasonably well.
文摘Three-dimensional simulation of a multiphase flow is performed using the EulerianEulerian finite volume method in order to evaluate the separation efficiency and velocity field of deoiling hydrocyclones.The solution is developed using a mass conservation-based algorithm（MCBA） with collocated grid arrangement.The mixture approach of the Reynolds stress model is also employed in order to capture features of turbulent multiphase swirling flow.The velocity field and separation efficiency of two different configurations of deoiling hydrocyclones are compared with available experimental data.The comparison shows that the separation efficiency can be predicted with high accuracy using computational fluid dynamics.The velocity fields are also in good agreement with available experimental velocity measurements.Special attention is drawn to swirl intensity in deoiling hydrocyclones and it is shown that the differences in velocity and volume fraction fields of different configurations are related to swirl distribution.
文摘In this study computational fluid dynamics (CFD) approach was used to study mixing in an Industrial gold leaching tank. The objective was to analyze the extent of mixing in the tank by producing visual images of the various mixing zones in the tank domain. Eddy viscosity plots that characterise the extent of mixing in the tank were generated in the flow field obtained by an Eulerian-Eulerian approach. The extent of mixing was found to be greatest in the circulation loops of the impeller discharge region and least at the top and bottom portions of the tank. Trailing vortices that contribute to some level of mixing were identified in between the impeller blades. This approach could be used to enhance optimum design of mixing vessels and to eliminate the need for pilot plants.
