Computational Fluids Dynamics based Studies on Entrance length characteristics for High Concentration Particulate Coal Ash-Water Mixture Disposal

Pipeline transportation is a preferred mode of particulate material transportation due to its inherent advantages over other conventional modes of transportation, in particular, the High concentration solid fluid mixture system is developed to save huge specific energy consumption and less wear and tear to pipeline and attrition among particles at very high particle loading ratio. Although many works have been done on these systems, there is scarcity on understanding of the basic fluid mechanics. Therefore, the current work is focused on determination of entrance length for such system. Effect of various parameters like solid fluid mixture concentration, and Bingham Reynolds number are also studied. It is found that the entrance length for solid fluid mixture flows at high solid concentration substantially depends on the solid concentration, and flow regime both. Further, for turbulent flows the entrance length is independent of solid concentration. Entrance length for such flows are found to be more in case of laminar flows than turbulent flows.