INVESTIGATION OF THE SHIFTING-PARAMETER AS A FUNCTION OF PARTICLE SIZE DISTRIBUTION IN A FLUIDIZED BED TRAVERSING FROM A FIXED TO FLUIDIZED BED

Accurate predictions of pressure drops in fluidized beds are of great importance in the industry. Up to date no satisfactory correlation exists to predict the pressure drop in a fluidized bed as the bed is traversing from one regime to another. In the present study the powered addition correlation [1] is investigated for this particular application. It has been found that this correlation is well suited for the investigated application

Computational study of stratified two phase oil/water flow in horizontal pipes

Paper presented at the 6th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, South Africa, 30 June - 2 July, 2008.Stratified oil/water two-phase flow in a horizontal tube is numerically simulated using commercial CFD package FLUENT 6.3. The simulations are based on Volume of Fluid (VOF) model. It solves a single momentum equation shared by the fluids, and the volume fraction of each of the fluid in each computational cell is tracked throughout the domain. The RNG k- model together with standard wall treatment as the nearwall modelling method is used for turbulence modelling. The effects of surface tension along the interface between two fluids are calculated using Continuum Surface Force (CSF) model. The simulation is performed in a time-dependent way so that the numerical stabilization could be achieved. The final solution which corresponds to steady-state flow is analyzed. Results of pressure drop, slip ratio, interface height and the axial velocity profiles are verified by experimental data. The predictions of pressure drop, slip ratio and interface height are observed to compare favourably with experimental measurements, and estimated flow quantities such as axial velocity profiles are also satisfactory.vk201