Influence of the porosity profile and sets of Ergun constants on the main hydrodynamic parameters in the trickle-bed reactors

• Validation of the CFD code on the basis of a experimental database.
• Selection of the optimum correlation for the radial and axial porosity profile in the bed.
• Estimation of Ergun parameters in the closure equation for the momentum exchange between phases.
• Influence of the ratio D/dp on values of hydrodynamic parameters computed has been investigated.

The Eulerian multiphase code has been applied for the comparative simulation of the experimental results obtained for varying flow rates of both fluid phases and for systems of various physicochemical properties used in the laboratory trickle-bed reactor (TBR). Therefore six different radial porosity profiles and three sets of the Ergun constants used in the relations defining the interphase momentum exchange have been implemented into the CFD code. The mean relative error of the pressure drop and of the averaged holdup as well as the standard deviation determined with respect to the experiments have been used as the criterion for the validation of the theoretical model. These values explicitly confirmed the necessity of applying the radial porosity profile in the beds of low values of the D/dp ratio i.e. for laboratory equipment in order to obtain accurate values of the pressure drop and the averaged holdup. They also enabled to select the optimum radial porosity correlation and the optimum Ergun constants in the relations of interphase momentum exchange which in consequence could be recommended for the modeling of the hydrodynamics in the laboratory TBR by means of the CFD code.