Heat transfer of ice slurry flows in a horizontal pipe: A numerical study

摘要

The thermal behavior of ethylene glycol-water ice slurry flowing through a horizontal heated tube is investigated numerically. The ice slurry is assumed to behave as a Newtonian fluid with effective properties depending on temperature and ice fraction. The 3D steady-state model includes the mass, momentum and energy conservation equations for the liquid-solid mixture as well as a transport equation for the ice particles which characterizes the balance between convective and diffusive fluxes. The diffusive flux includes those induced by the shear rate gradients, the spatial variation in viscosity and the particle settling. The heat and mass exchanges between the ice particles and the carrier liquid are modeled through source terms. The model is validated against experimental data from the open literature and applied to laminar and turbulent flows. Some important heat transfer characteristics of melting are obtained including the axial distributions of the heat transfer coefficient, the bulk and wall temperatures, the ice volume fraction and the melting rate. They show significant differences from corresponding distributions for non-melting flows. The effects of the wall heat flux and other operating parameters on these quantities are presented and analyzed.