CFD-BASED INVESTIGATION OF POWER PLANT FLY ASH HIGH CONCENTRATION SLURRY FLOW THROUGH HORIZONTAL PIPE CONTRACTION
More than half of the world's electricity is produced by burning large amounts of coal in thermal power plants and at the same time producing huge quantities of coal ash. Hydraulic transportation of coal ash from coal fired thermal power plants to ash ponds, using high concentration slurry disposal systems (HCSD) is safe, reliable, economical and attractive method due to its low maintenance costs, round the year availability and being environmentally friendly. Present study reports simulated pressure drop for the flow of high concentration fly ash slurries (in the range of 50 70 % by weight) through sudden and conical pipe contractions at various flow velocities using available experimentally obtained rheological parameters. For calculations the finite volume method is applied, which is the most commonly used and gives very good results in the analysis of problems in fluid mechanics and heat transfer. The method in this paper is adapted for simulation of flow of viscoplastic materials whose behavior is described by viscoplastic (Bingham) model. The simulation results are compared with corresponding analytical solutions and experimental data and good agreement between the results is shown.