The experiment was conducted to explore the hydrodynamics in a conical column with a height of 3.00 m, and a taper angle of 1.91°. Three regimes occur in succession with increasing superficial gas velocity. Ove...The experiment was conducted to explore the hydrodynamics in a conical column with a height of 3.00 m, and a taper angle of 1.91°. Three regimes occur in succession with increasing superficial gas velocity. Overall gas holdup increases with an increase in gas velocity and a decrease in solid concentration or static slurry height. Axial solid holdup becomes more uniform with increasing gas velocity, while axial gas holdup decreases from the bottom to the top. Both dry and wet pressure drops across the gas distributor increase with an increase in superficial gas velocity.展开更多
Understanding the mesoscale structure and regime transition in bubble columns is of great significance for reactor design and scaleup.Based on the energy-minimization multiscale(EMMS)model,a noncooperative game model ...Understanding the mesoscale structure and regime transition in bubble columns is of great significance for reactor design and scaleup.Based on the energy-minimization multiscale(EMMS)model,a noncooperative game model with constraints is proposed to investigate the structural properties of gas-liquid systems in which small and large bubbles are chosen as players and the energy consumption form the objective function.The conservation equations of the system can be regarded as the constraints of the game.For the formulated noncooperative game model,the concept of the generalized Nash equilibrium(GNE)is used to characterize the solution.An algorithm is developed to numerically compute the GNE and some important structural parameters in the system.The numerical results show the existence of the GNE for all values of the superficial gas velocity Ug.As Ug varies,the trends in the state variables can be observed and the critical point of Ug identified.The overall trend of the flow regime transition agrees with the original EMMS model and experimental results,although the GNE calculation also reveals different single-bubble dominant mechanisms with increasing Ug.展开更多
文摘The experiment was conducted to explore the hydrodynamics in a conical column with a height of 3.00 m, and a taper angle of 1.91°. Three regimes occur in succession with increasing superficial gas velocity. Overall gas holdup increases with an increase in gas velocity and a decrease in solid concentration or static slurry height. Axial solid holdup becomes more uniform with increasing gas velocity, while axial gas holdup decreases from the bottom to the top. Both dry and wet pressure drops across the gas distributor increase with an increase in superficial gas velocity.
基金The authors would like to thank Prof.Lei Guo for his encour-agement and profound insight to realize the game hidden in the EMMS model.The authors also thank Prof.Jinghai Li for his encour-agement and valuable suggestions.The paper is supported by the National Natural Science Foundation of China under Grant 91634203,61304159,11688101,and by the National Center for Mathematics and Interdisciplinary Sciences.
文摘Understanding the mesoscale structure and regime transition in bubble columns is of great significance for reactor design and scaleup.Based on the energy-minimization multiscale(EMMS)model,a noncooperative game model with constraints is proposed to investigate the structural properties of gas-liquid systems in which small and large bubbles are chosen as players and the energy consumption form the objective function.The conservation equations of the system can be regarded as the constraints of the game.For the formulated noncooperative game model,the concept of the generalized Nash equilibrium(GNE)is used to characterize the solution.An algorithm is developed to numerically compute the GNE and some important structural parameters in the system.The numerical results show the existence of the GNE for all values of the superficial gas velocity Ug.As Ug varies,the trends in the state variables can be observed and the critical point of Ug identified.The overall trend of the flow regime transition agrees with the original EMMS model and experimental results,although the GNE calculation also reveals different single-bubble dominant mechanisms with increasing Ug.
