Application of CPFD method in the simulation of vertical dense phase pneumatic conveying of pulverized coal

Abstract

Flow stability is a key issue to be addressed by the development of dense phase pneumatic conveying. Flow patterns are closely related to flow stability. From the view of experimental materials, angle of repose, packing density and tapped density and flowability results show that the tested pulverized coal approximated a Geldart's group C powder with strong cohesion. This study contributes with a computational particle fluid dynamic (CPFD) simulation which is based on the numerical solution of continuity and momentum balance equations in a three-dimensional (3-D) horizontal pipeline. A novel correction model was developed, describing interaction among particles and between fluid and particles decided by the experiment mentioned before. The drag force model was done with the parameter sensitivity analysis. The errors of particle velocity profiles and pressure drop predicted by the CPFD approach were below 5% for the stable cases. What's more, the six different flow patterns were predicted by the CPFD approach embedded in the correction model, which was confirmed by electrical capacitance tomography (ECT) in our experimental facility. With the help of our correction model and some suggestions, the CPFD approach may help people to predict dense-phase pneumatic conveying of cohesive powders, such as coal.