Numerical Prediction Of Ice Crystal Growth Due To Film Flowing Down A Vertical Cooled Plate

A finite volume numerical code has been developed to numerically represent 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 due to suspended ice crystals is accounted for in the use of effective values of thermal conductivity, viscosity, thermal difiusivity, and specific heat as function of volumetric concentration of ice crystals in the falling film. Nusselt number, overall heat transfer coefficient between the fluid and cooled plate, and ice crystal growth rate were calculated for different film thickness 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 flow rate).35733744Ahuja, A.S., Augmentation of Heat Transport in Laminar Flow of Polystyrene Suspensions -I. Experiment and Results (1975) Journal of Applied Physics, 46, pp. 3408-3416Burns, A.S., Stickler, L.A., Stewart, W.E., Solidification of an Aqueous Salt Solution in a Circular Cylinder (1992) ASME Transactions. J. Heat Transfer, 114, pp. 30-33Charunyakorn, P., Sengupta, S., Roy, S.K., Forced Convection Heat Transfer in Microencapsulated Phase-Change Marterial Slurries: Flow in Circular Duct (1991) Int. J. Heat Mass Transfer, 34, pp. 819-832Fang, L.J., Cheung, F.B., Linehan, J.H., Pedersen, D.R., Selective Freezing of a Dilute Salt Solution on a Cold Surface (1984) Journal of Heat Transfer, 106, pp. 385-393Hale, D.V., Hoover, M.J., O'Neil, M.J., (1971) Phase-change Materials Handbook, , NASA CR-61363Hart, R., Thornton, F., Microencapsulation of Phase-Change Materials (1982) Final Report Contract No. 82-80, , Department of Energy, OhioKasza, K.E., Chen, M.M., Improvement of the Performance of Solar Energy or Waste Heat Utilization Systems by Using Phase-Change Slurry as an Enhanced Heat-Transfer Storage Fluid (1985) Journal of Solar Energy Engineering, 107, pp. 229-236Leal, L.G., On the Effective Conductivity of Dilute Suspension of Spherical Drops in the Limit of Low Particle Peclet Number (1973) Chem. Engng. Commun, 1, pp. 21-31Levich, V.G., (1962) Physiochemical Hydrodynamics, pp. 669-672. , Engle-wood Cliffs, NJNir, A., Acrivos, A., The Effective Thermal Conductivity of Sheared Suspensions (1976) J. Fluid Mech., 78, pp. 33-48Rutgers, I.R., Relative Viscosity of Suspensions of Rigid Spheres in Neotonian Liquids (1962) Rheologica Acta, 2 (4), pp. 305-348Patankar, S., (1980) Numerical Heat Transfer and Fluid Flow, , Hemisphere Publishing Co., New YorkSohn, C.W., Chen, M.M., Heat Transfer Enhancement in Laminar Slurry Pipe Flows with Power Law Thermal Conductivities (1984) Journal of Heat Transfer, 106, pp. 539-542Stewart Jr., W.E., Kaupang, R.L., Tharp, C.G., Wendland, R.D., Stickler, L.A., An Approximate Numerical Model of Falling-Film Ice Crystal Growth for Cool Thermal Energy Storage (1993) ASHRAE Transactions Research, 99 (PART I), pp. 347-354Vand, V., Viscosity of Solutions and Suspensions (1948) J. Phys. Coll. Chem., 52, pp. 300-32