Compared to the traditional lumped-parameter model, computational fluid dynamics （CFD） attracted more attentions due to facilitating more accurate reactor design and optimization methods when analyzing the heat tran...Compared to the traditional lumped-parameter model, computational fluid dynamics （CFD） attracted more attentions due to facilitating more accurate reactor design and optimization methods when analyzing the heat transfer in the industrial packed bed. Here, a model was developed based on the CFD theory, in which the heterogeneous fluid flow was resolved by considering the oscillatory behavior of voidage and the effective fluid viscosity. The energy transports in packed bed were calculated by the convection and diffusion incorporated with gaseous dispersion in fluid and the contacting thermal conductivity of packed particles in solids. The heat transfer coefficient between fluid and wall was evaluated by considering the turbulence due to the packed particles adjacent to the wall. Thus, the heat transfer in padded bed can be predicted without using any adjustable semi-empirical effective thermal conductivity coefficient. The experimental results from the literature were employed to validate this model.展开更多
Along with the fast development of computer technology and measurement techniques, fundamental research on fluidization is faced with both new challenges and opportunities. Among others, great attention should be focu...Along with the fast development of computer technology and measurement techniques, fundamental research on fluidization is faced with both new challenges and opportunities. Among others, great attention should be focused on the meso-scale structure of fluidized beds, to study the quantitative prediction theory and optimum control method for the meso-scale structure of fluidized beds, and to establish the modeling of the relationship between meso-scale structure and momentum transfer, heat transfer, mass transfer, and chemical reaction. These efforts, combined with advanced computer simulation, are expected to solve difficult problems in optimum control and scale-up of fluidized bed processes and equipment.展开更多
基金Supported by National Natural Science Foundation of China(21676266,21676269)the "Strategic Priority Research Program" of the Chinese Academy of Sciences(XDB17020100)the National Key Projects for Fundamental Research and Development of China(2016YFA0202801)
文摘Compared to the traditional lumped-parameter model, computational fluid dynamics （CFD） attracted more attentions due to facilitating more accurate reactor design and optimization methods when analyzing the heat transfer in the industrial packed bed. Here, a model was developed based on the CFD theory, in which the heterogeneous fluid flow was resolved by considering the oscillatory behavior of voidage and the effective fluid viscosity. The energy transports in packed bed were calculated by the convection and diffusion incorporated with gaseous dispersion in fluid and the contacting thermal conductivity of packed particles in solids. The heat transfer coefficient between fluid and wall was evaluated by considering the turbulence due to the packed particles adjacent to the wall. Thus, the heat transfer in padded bed can be predicted without using any adjustable semi-empirical effective thermal conductivity coefficient. The experimental results from the literature were employed to validate this model.
基金supports on this work from National Natural Science Foundation of China under Grant No.20736004the State Key Development Program for Basic Research of China(973 Program) under Grant No.2009CB219904
文摘Along with the fast development of computer technology and measurement techniques, fundamental research on fluidization is faced with both new challenges and opportunities. Among others, great attention should be focused on the meso-scale structure of fluidized beds, to study the quantitative prediction theory and optimum control method for the meso-scale structure of fluidized beds, and to establish the modeling of the relationship between meso-scale structure and momentum transfer, heat transfer, mass transfer, and chemical reaction. These efforts, combined with advanced computer simulation, are expected to solve difficult problems in optimum control and scale-up of fluidized bed processes and equipment.
