Modelling of heat transfer in a packed bed column

Abstract

The CFD modelling of heat transfer in the packed bed column in the laminar and turbulent fl ow regimes has been presented. Three numerical grids with different densities were generated for the packed bed column. The modelling was performed with the use of the Porous Media Model for treating the fl ow inside a porous structure. The standard k- model along with the logarithmic wall functions for the turbulent fl ow range was used. The infl uence of the mesh size on the accuracy of the fl uid fl ow was studied. Both radial and axial direction temperature distributions have been compared with the experimental data 1 and the values calculated from a 2DADPF model. A good agreement between the experimental and the predicted values of the pressure drop, temperature distributions and heat transfer coeffi cient was obtained.

Effect of freeboard deflectors on the temperature distribution in packed beds

“…Although the porous media is applied, the effective thermal conductivity in the packed bed is not solely based on the weighted solid phase (k s ) and gas phase (k f ) thermal conductivities [14,36]. In modelling packed beds, there have been several attempts to derive empirical models for the effective Model-I Effective thermal conductivity derived empirically from the experimental data of Wen and Ding [55] compared to that using the empirical fits from Yagi and Kunii [25] and Vortmeyer and Adam [47] when applied in packed beds up to 400 C.…”

“…Such challenges include, a better understanding on the variation of the effective thermal conductivity over a range of Reynolds (Re) numbers and temperatures, the influence of wall effects on the axial temperature distributions (within the bed) and the effects of porosity. The task of resolving these factors in relation to modelling particle drying and fixed-bed combustion is exacerbated by the prevalence of studies with either extremely low Reynolds numbers [30e32]; the use of glass, metallic or other nondrying particles [2]; poorly defined boundary condition data [33,34] and/or that most packed bed reaction models are simulated as porous media [14,35,36].…”

A pore scale study on fluid flow through two dimensional dual scale porous media with small number of intraparticle pores

“…Furthermore, three types of porosities can be defi ned for a dual scale porous media as interparticle, intraparticle and bulk porosities. These porosities can be found by using below equalities: (1) where ε p , ε f and ε t are the intraparticle, interparticle and bulk porosities, respectively. The volumes of intraparticle, interparticle and total pores are shown by V vp , V vf and V t , respectively.…”