Powder Technology, Vol.318, 46-61, 2017
Convective heat transfer in slurry flow in a horizontal Y-shaped branch pipe
This work is involved with the three-dimensional numerical prediction of the thermo-fluidic transport characteristics of fly ash-water slurry in a Y-shaped branch pipe. Spherical coal fly ash particles are considered as the dispersed phase. The fly ash particles are having mass median diameters of 13 and 34 mu m, mean flow velocity ranging from 1 to 5 m/s and concentration ranges from 10 to 50% by volume. The granular Eulerian multiphase model following a finite volume approach is used to perform the numerical simulation. The turbulent transport is addressed by the RNG k-epsilon turbulence model. The novelty of the work is the analysis of the convective heat transfer for the fly ash-water slurry flowing through the branch pipeline. The results reveal that increasing the size of the fly ash particles, the convective heat transfer coefficient increases for all the velocities in the range. For smaller particle size, the inlet pipe has more pressure drop than the outlet pipes at smaller velocity and vice versa at higher velocity. For larger particle, the outlet pipes have more pressure drop than the inlet pipe for all the velocities. Moreover, the pressure drop and heat transfer increase because of the formation of two pairs of counter-rotating stream wise vortices at the downstream of the bifurcation. (C) 2017 Elsevier B.V. All rights reserved.