Effect of axial conduction on the ice crystal growth in laminar falling films

A finite volume numerical code has been developed to numerically approximate the rate of ice crystal growth in a laminar falling film flowing down a cooled vertical plate. The governing energy equation contains the phase energy as the source term. Enhancement of heat transfer as a result of suspended ice crystals is accounted for in the use of effective values of thermal conductivity, viscosity, thermal diffusivity, and specific heat as function of volumetric concentration of ice crystals in the falling film. Nusselt number, overall heat transfer coefficients between the fluid and cooled plate, and ice crystal growth rate were calculated for different film thicknesses with and without axial diffusion. Nusselt number and ice crystal growth rates were found to be dependent on film thickness. Axial diffusion effects were found to be negligible for larger film thickness (large flowrate). (C) 1999 Elsevier Science Ltd and IIR. All rights reserved.22538940