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• Application of the Euler-Euler method to CFD modelling of the flow of ice slurry. • Low slip velocity of solid particles. • Highest slip velocities are observed near the channel sidewalls. • Homogeneous flow, lower border velocities for downward compared to upward flow. • Flow map of ice slurry for vertical flow in slit channel. In this article, the Euler-Euler method was applied to CFD modelling of adiabatic ice slurry flow, for different flow directions in a vertical slit channel. The mean relative accuracy of determining pressure drops compared to experimental studies was 5.6%. Calculations showed that the relative slip velocity and the effect of flow direction on slip velocity increase with decreasing carrier fluid concentration, decreasing mean flow velocity, and decreasing mean solid particles volume fraction. The mean particle slip velocity does not exceed 4%, and local slip velocity values can be 58% of the mean suspended solids flow velocity. For heterogeneous flow, the highest slip velocities occur at a distance of 15% of the channel width from the channel sidewalls. The shape of the solid particles distribution profile is determined by the mean flow velocity and the mean solid particles volume fraction. Excluding the area at a distance of 8% of the channel width from the sidewall where local maximum (for low velocities) and minimum (for higher velocities) values may occur, the profile is stabilised in the central part of the channel. In this study, the boundary curves between heterogeneous and homogeneous flow were determined for ice slurry flow in a vertical slit channel. [ABSTRACT FROM AUTHOR]

• Flow resistances of ethanol ice slurry in a vertical slotted channel. • Determination of dynamic plastic viscosity and shear stress of ethanol ice slurry. • Impact of flow direction, settling velocity on flow resistance. • Dimensionless relationships for the determination of Fanning friction factors. • Generalized non-Newtonian fluid flow through a vertical slit channel. The paper presents the results of experimental flow investigations of an ethanol-based ice slurry flowing up and down a vertical slit channel. The impact of flow direction, carrier fluid concentration, ice mass fraction and mean velocity on pressure drop values has been investigated. Stronger mutual interaction between the phases on flow resistances was observed for low carrier fluid concentrations and in the laminar range of ice slurry flow. The measured resistance values for downward flow in the laminar area were 6–10% higher than the pressure drops for upward flow, while in the turbulent flow area they were 1–8% higher. Using the generalized non-Newtonian fluid model, the authors have proposed equations for calculating the friction factors for a vertical slit channel and various flow directions. [ABSTRACT FROM AUTHOR]

Abstract: In this paper we present results of the studies of ice slurry flow in horizontal tubes. The possibility of treating the rheological parameters of ice slurry as being those of Bingham fluid was confirmed. The values of parameters (mass fraction, flow velocity) corresponding to the laminar, intermediate and turbulent flow were determined which permits to optimize the flow in the systems working with this cooling agent. Critical flow velocity and mass fraction of ice values were determined thereby; they correspond to a change in character of an ice slurry flow from a laminar to turbulent motion. Experimental results were compared to the analytical results, based on the Hedström and Tomita algorithms (the laminar and turbulent flow, respectively). The comparison showed a very good agreement between these data. [Copyright &y& Elsevier]

Abstract: In this paper, we analyzed the possibility of the simulations of ice slurry flow based on the known CFD procedures, for both Bingham fluids and mulitiphase flow models (the mixture and Eulerian models). It was shown that in the laminar region, the models selected (the Bingham and mixture model) gave a correct description of momentum transfer. In the turbulent range, corresponding to low values of the Reynolds number, the best agreement between experimental and simulation results (for the single-phase as well as for the multiphase Eulerian model) was obtained when the RNG k–ε turbulence model with the enhanced wall treatment algorithm was selected. [Copyright &y& Elsevier]

Abstract: This paper presents results of studies on heat transfer in ice slurry flows through horizontal tubes. On the basis of the energy equation and experimental results, the authors developed their own dimensionless relationships to determine local values of heat transfer coefficients for turbulent and laminar flows. Appropriate parameters were introduced to these expressions, in order to account for the effects of the following: the rheological properties of ice slurry, phase change, and the multiphase flow character. The second part of this paper discusses the possibility of modeling heat transfer in ice slurry tube flows using the CFD (fluent) methods. Correct description of heat transfer in ice slurry flows in tubes was made possible by assuming a single-phase model for Bingham fluid, and the enthalpy-porosity method for the analysis of melting, as well as by taking into account variations of the heat conductivity in a moving suspension. [Copyright &y& Elsevier]