چكيده به لاتين
In this study, numerical simulations of gas-liquid flow behavior of bubble cap tray have been done. The aim of this work is to develop a Computational Fluid Dynamic (CFD) model enable of predicting the hydrodynamic parameters of any desired system. The CFD analysis and simulations were performed by using the Commercial package FLUENT 16. A transient three-dimensional model in Eulerian framework with standard k-ε turbulence model has been developed, ignoring mass and energy transfer equations. For this purpose a new correlation of liquid hold-up has been developed using Genetic Algorithm based on the experimental clear liquid height data. By substitution of this correlation in drag force relation, the source term has been added to the momentum equations. The standard k-ε model has been used as the Turbulence model. In order to validate the results of the simulation, the experimental data of clear liquid height which was obtained with Azar Energy Company, has been applied. Finally the error of 13% has been observed compared to experimental data. The results showed that the using of variable drag coefficient decrease the error from about 22% to about 13%. Actually constant value of 0.44 for drag coefficient which was suitable for uniform bubbly flow but not appropriate for froth or spray regimes. Simulations have been carried out over a wide range of liquid and vapor flow rates and the predicted results have been found to be in reasonable agreement with the experimental data. Velocity and pressure distributions, clear liquid height, froth height, and liquid holdup fraction in the froth region have been predicted, which are beneficial in analysis and design of the column trays.
Keywords: Computational Fluid Dynamics (CFD), Simulation, Bubble cap tray, Hydrodynamic parameter.
