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The paper presents the phenomena accompanying the processes of non-adiabatic transport of ice slurry with ice mass fraction values below 20% in the transport sections of the system, assuming the conditions of significant changes in hydrostatic pressure. The subject of the analysis presented herein was to indicate the influence of hydrostatic pressure values on melting and secondary recrystallisation phenomena in the case of medium expansion in a vertical shaft pipeline and a three-chamber PES distributor. The paper proposes a computational model to determine the mass fraction of ice in the downstream section of the supply system: upstream and downstream of the PES distributor. The presented calculation results indicate that a reduction in the mass fraction of ice in the range of 0.004% per 1 m of the pipeline could be observed in vertical shaft pipelines. Maximising the enthalpy flux of the slurry at the inlet to the secondary circuit and minimising the temperature of the return water to the chiller favours mixing rates in the PES three-chamber distributor below 7%, which increase as the mass fraction of ice decreases. • Ice slurry applications in central air-conditioning systems of mining plants. • Ice slurry flow and heat transfer in shaft pipelines and PES distributors. • Ice slurry melting and recrystallisation in primary and secondary circuits. [ABSTRACT FROM AUTHOR]

The paper presents the results of experimental research of pressure drop and heat transfer coefficients of ice slurry during its flow through tubes of rectangular and slit cross-sections. Moreover, the work discusses the influence of solid particles, type of motion and cross-section on the changes in the pressure drop and heat transfer coefficient. The analysis presented in the paper allows for identification of the criterial relations used to calculate the Fanning factor and the Nusselt number for laminar and turbulent flow, taking into account elements such as phase change, which accompanies the heat transfer process. Ice slurry flow is treated as a generalized flow of a non-Newtonian fluid. [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]