Slurry flow characteristics through a horizontal pipeline at different Prandtl number

Abstract

The settling behavior of solid particles in the slurry pipeline leads to bed formation and sedimentation at the bottom of the pipeline. This in turn causes the blockage of the pipeline resulting in more energy consumption and a pressure drop in the slurry pipeline. The present work investigates the effect of the different Prandtl numbers on the slurry flow characteristics through a horizontal pipe. Since the flow is a liquid-solid mixture, therefore, a steady-state three-dimensional Eulerian two-phase model in combination with the RNG k-ε turbulence model is implemented for the current simulation in the commercial software ANSYS FLUENT. Numerical predictions and procedures for the mixture of solid concentrations are generally in good agreement with the past experimental data available in the literature. Slurry flow features are examined at four different Prandtl numbers i.e., 2.88, 3.42, 4.62 and 5.83 for different-sized glass beads (125, 200, 275, 350 and 440 μm) slurry for the concentration ranging from 40 to 60% (by weight) at a mean flow-velocity of 5 m/s. The findings show that the pressure drop rises with the escalation in particle sizes and Prandtl number for chosen efflux concentration range. Furthermore, low Prandtl fluid demonstrates relatively higher granular pressure, temperature and wall shear stress, which further increases with raise in solid concentration and particle size. In addition, higher Prandtl number fluid demonstrates maximum specific energy consumption (SEC) for every particle and efflux concentration range. • 3D CFD modeling of slurry flow via horizontal straight pipe is investigated. • Effect of different Prandtl number on slurry flow characteristics is studied. • Effect of particle size and concentration on slurry pressure drop is presented. • At lower Prandtl number, maximum granular pressure and temperature is established. • Transportation of slurry with higher Prandtl fluid is more energy efficient.