Concentration distribution and viscosity of ice-slurry in heterogeneous flow

Mathematical modeling of two phase flows, especially liquid-solid flows is very complex. Especially when a distribution of the solid phase in a carrier liquid is not homogenous but heterogeneous or even when a moving or stationary bed occurs. In this case, the theological characteristics of suspension are changing and affect transport characteristics. Therefore, the slurry flow may present a Newtonian and non-Newtonian fluid as well, depending on the operation characteristics. In this paper the fully suspended ice-slurry flow in a horizontal pipe is analysed, The model allows us to avoid the definition on what kind of fluid ice-slurry is present. For the taken ice-particle diameter, the ice-concentration profiles depending on various average velocities and pipe diameters are shown. The viscosity of the ice-slurry is presented, depending on average concentration, velocity, pipe diameter and ice-particle size, The results of the analysis have shown that the ice slurrys can be treated as Newtonian-fluid at higher average velocities, and lower average concentrations as well. As the ice concentration increases and velocity decreases the viscosity depends not only on the ice concentration but also on the average velocity and the pipe diameter. The ice-slurry behaves then as a non-Newtonian fluid. The results show also the area where the safe operation of an ice-slurry-district-cooling system can be performed. (C) 2002 Elsevier Science Ltd and IIR. All rights reserved.